From patchwork Wed Aug 1 15:19:50 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552457 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3218314E2 for ; Wed, 1 Aug 2018 15:17:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 23B2B2B5AF for ; Wed, 1 Aug 2018 15:17:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 17A162B703; Wed, 1 Aug 2018 15:17:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9A4E82B5AF for ; Wed, 1 Aug 2018 15:17:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9D2956B0276; Wed, 1 Aug 2018 11:17:17 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 934A06B0278; Wed, 1 Aug 2018 11:17:17 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 789DF6B0279; Wed, 1 Aug 2018 11:17:17 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qk0-f200.google.com (mail-qk0-f200.google.com [209.85.220.200]) by kanga.kvack.org (Postfix) with ESMTP id 4677A6B0276 for ; Wed, 1 Aug 2018 11:17:17 -0400 (EDT) Received: by mail-qk0-f200.google.com with SMTP id v65-v6so16972030qka.23 for ; Wed, 01 Aug 2018 08:17:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=dPzbJJIeJgfn8++cxkOJb5Dz/B61/Buo1muVR4A4+7E=; b=PhdPWxsj1R0gICgabrvvcnThiCUVaROwpqTNjhTWA4EFN1b6+IfkNjXKug+tCcPCd2 jXRQb7P2jZNbm9WpnEROmPZgJoAeo1Et4YBUVdkcSTzoWJNGAgNVAhZg5M3ScI0b0W+J GJxJVCRvzO3KUxViy8kU1Ye0tSk8t/ObJIuw4McANRq3d/xfnj2aIwyoLTeyZ8H7m0r7 lxGFO3gsuDKuG5YETHFkr6FV1QCJJGsoHXGJetdSSCOLatyQJEIIYbc4iAyIZG1M/H7m u+WD+qd2XPikQKz1mSxIhNXaR6Fb6gtW5UautlghufMYBxOYw+Et2sfbVwp9RgOaXAoL 9j3g== X-Gm-Message-State: AOUpUlG+174itmX4Ka0Y3oiTxNwvII6toMZE9pYp6uW8jRG1JJPk5Kna k14OlJLig5Kp+398Tn7dCmjj91EZSfI98Uv5Cts9NXzjPLWgeAm/3Kn+OywsPAj09pY21z+o7oW EwXSwEN/xYJJR1GOn/dVZqobaiWwVK6PehdY+Iz24z0i6yegY+ZtccruOF0Y0gaGjcO/akv/H37 eAVVzrAq7yjC99hS9YBCVlHSOvwr8JNIm6V2WbxCtuEYAttHCamFQcJg0ZkMoREjJtX3FGox2QG Kkh6a1NaVQ5ZV9GBO9nCk4tLP0GGD9VvwFfwfWS7vwqk37bypx2F1FuA3Q95yacUsL+oY6G7RzN HCk4YJP6/WBMsZpSxP0jTV0fWU3+/c+CQGTPZQgxpK+65SClXmFoTm6WnMjvvLsC+9GmRiBoMzv P X-Received: by 2002:a37:6e01:: with SMTP id j1-v6mr25140669qkc.70.1533136637036; Wed, 01 Aug 2018 08:17:17 -0700 (PDT) X-Received: by 2002:a37:6e01:: with SMTP id j1-v6mr25140634qkc.70.1533136636493; Wed, 01 Aug 2018 08:17:16 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136636; cv=none; d=google.com; s=arc-20160816; b=fIkfNYPRS4L2lGJLIiyKpH83QjZ5Sf22rOlCfbop5CB66ezr1sa8Set+dQjRpvaDRy 87nWCI/UXhb15HLDENqYq4VAW/AH+s30WieI3tOeUmcTrF0CbAKjdr+8QrUBzLn7O6FM U8MzfQjsjoArEHDuSuyXJthOVzBD21f7Bap7pAWhFmDNLrIeIfPmdiiY5radv7kFco0U Dlk+JtL2GPFscZ+YcvenXR5Vo6JI1TkRBa97QhRdfG31eh3t1AMR3gGYaUmTLEbm/u67 DYoOx7/mWk5d/7tmp/AZFbquMlboP47Dj5EAaj12MwxBhXcvOZz82I04nNMCGy11lZDX 4iRg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=dPzbJJIeJgfn8++cxkOJb5Dz/B61/Buo1muVR4A4+7E=; b=W9hq+hfRFqoOftiiIoVIAK2xVSsJB+Bx8XooR53MYN6HrURyVDQ8Dc10OmWfNt0xx7 nd2DtvD5L4/PYCgUlmwskbOAs4yjNecsyOPdXOYf++CTgHs6uP8L/v9VKPX0CdzzrImM XtlNDgaXL7XHi1Y6OKHD/SRwKQRUQ54Rd4nNI53U8dIm6r66V609b7ess6Cv5Ejibael 0qLQMTi3MxZO6qw/kmehXAxlu3atgUCSDfBuR4QJLIxL8d+wtMIKK7G4T+n3HP+gCfm3 QbFqW7lMO5TxE9/WGPk/5XmmqIK6mMw0OAXECo6IdZl1ja4U9CbNYG0xUrBRSEYsYV+u X22g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=vjkKAP6u; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id d16-v6sor8388645qtc.43.2018.08.01.08.17.16 for (Google Transport Security); Wed, 01 Aug 2018 08:17:16 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=vjkKAP6u; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=dPzbJJIeJgfn8++cxkOJb5Dz/B61/Buo1muVR4A4+7E=; b=vjkKAP6ubSVRmeQnLIA1gqmu8OAqsEHegFTBIDM1/gU9CHgInYOeLeKoL9P1dcM5B8 F/g3ROFEMdcJg5dDR13yU3joj5UQWsjMnRDx0MouUUBe7DxHXOPd32pQJYysbbJZLLgH xlEMIfX9TjiQ+72+ycMhG1eMvquOXetDj2NhDc9pedmsJU9lRUIPuf8Q0mfCT+Z74Pjf yCDRJ+CA+TaGOqToLtodun/RLgCBPA0aO6HVisiIC05uiTi+4FORM5tjzYEcsdrHNd6T wvNUSYsmzHT8lv5HXIX1e6XMrF/B/D9vp76MjyyLkRYtFV2y5qHoKO2H9z/aPvzbK0ua 6Tqw== X-Google-Smtp-Source: AAOMgpcPejOKXggv4n4mtOX7TLOUkJf2P1Z5h5cgj8sR5QAuAUlmFjmyKcvWXIdnmZyAlGMFPVa2rw== X-Received: by 2002:ac8:28ca:: with SMTP id j10-v6mr26812646qtj.9.1533136636070; Wed, 01 Aug 2018 08:17:16 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id 127-v6sm10610783qkn.78.2018.08.01.08.17.14 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:15 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 1/9] mm: workingset: don't drop refault information prematurely Date: Wed, 1 Aug 2018 11:19:50 -0400 Message-Id: <20180801151958.32590-2-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP From: Johannes Weiner If we keep just enough refault information to match the CURRENT page cache during reclaim time, we could lose a lot of events when there is only a temporary spike in non-cache memory consumption that pushes out all the cache. Once cache comes back, we won't see those refaults. They might not be actionable for LRU aging, but we want to know about them for measuring memory pressure. Signed-off-by: Johannes Weiner --- mm/workingset.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/mm/workingset.c b/mm/workingset.c index 40ee02c83978..53759a3cf99a 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -364,7 +364,7 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker, { unsigned long max_nodes; unsigned long nodes; - unsigned long cache; + unsigned long pages; /* list_lru lock nests inside the IRQ-safe i_pages lock */ local_irq_disable(); @@ -393,14 +393,14 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker, * * PAGE_SIZE / radix_tree_nodes / node_entries * 8 / PAGE_SIZE */ - if (sc->memcg) { - cache = mem_cgroup_node_nr_lru_pages(sc->memcg, sc->nid, - LRU_ALL_FILE); - } else { - cache = node_page_state(NODE_DATA(sc->nid), NR_ACTIVE_FILE) + - node_page_state(NODE_DATA(sc->nid), NR_INACTIVE_FILE); - } - max_nodes = cache >> (RADIX_TREE_MAP_SHIFT - 3); +#ifdef CONFIG_MEMCG + if (sc->memcg) + pages = page_counter_read(&sc->memcg->memory); + else +#endif + pages = node_present_pages(sc->nid); + + max_nodes = pages >> (RADIX_TREE_MAP_SHIFT - 3); if (nodes <= max_nodes) return 0; From patchwork Wed Aug 1 15:19:51 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552459 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A4D9715E9 for ; Wed, 1 Aug 2018 15:17:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 954302B5AF for ; Wed, 1 Aug 2018 15:17:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 892542B703; Wed, 1 Aug 2018 15:17:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6CB752B5AF for ; Wed, 1 Aug 2018 15:17:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C6DC46B0278; Wed, 1 Aug 2018 11:17:20 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id B58A66B027A; Wed, 1 Aug 2018 11:17:20 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 982E56B027B; Wed, 1 Aug 2018 11:17:20 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qt0-f199.google.com (mail-qt0-f199.google.com [209.85.216.199]) by kanga.kvack.org (Postfix) with ESMTP id 67CAE6B027A for ; Wed, 1 Aug 2018 11:17:20 -0400 (EDT) Received: by mail-qt0-f199.google.com with SMTP id e14-v6so15809056qtp.17 for ; Wed, 01 Aug 2018 08:17:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=qQSBTnxNlt3eRiLy52Sx1ZjqVOe8sAaRJJ76RsaU+wI=; b=cSK670P9DQoTbo5Mh/4uB86KowSPhvlpJlyzq7NHyPLpS9elA82Q64n6OLJxCVoJSP 6DFwyr8skRxye7Ac5NGeFFh/i+H5sMHN1V0Okv1XxcRygRkFZu/Ngn1tlFXioGKBY3NY gLUqXBwmU/qd2p9OG2eaNaGOoUDVg11g6mXWu+6dmQKOqb1Gjj/46jkOixc+iRSncqg/ JW2FUUfvlLV5xk1fgrZiov3bbLT61OZ2EZLeqsLNcCMoY1BVl4NAuifa/6yS6uqymKbJ 5ZsoaVuAzo0S92WPYKVjYBEwFQ3UH5PL/YJHFohfS1qagHYHFlQeyijM+7UXrxseKn+4 rJcA== X-Gm-Message-State: AOUpUlEXlIixtE6C88B1zN95iH4GNjoGCM62S3lIA5Ttj11Yjj4fqkGp Q2WFSLNn8+BzL6Fef8dhmgtdpAkdAOTiRB9W6YSOGIEIlSTu8NJslnKqvxJLA8nE2Si1RQFb/vl QwTWGH+oaNYF5pg5+zhYkOGwLJcHhUVqYA7s2MY9ue0gHN+Z0fdDDtJpbW8kpmhACjj0Mlqbytt 3ITYvVRiitCLnrFP7lhh2Km6nDI62K0U2vHidfE+lYLWDc+NamQHROSFWBb53CHJzU5Gb4fUMU4 cEDVXlmvLOMYEebFgpj0UUCPdq/eo63nR051bxl3o41y6EKxi6NqQnWCx6AuGiq7QpVFzKfMYcB My1sTczdJc16S/rVP3djAQ9g+4v2AHilj2j6afjzkk8+V2j/VekXa/Fm20n6/pt7ysIz6W0jURn 7 X-Received: by 2002:a37:6dc4:: with SMTP id i187-v6mr24668883qkc.34.1533136640143; Wed, 01 Aug 2018 08:17:20 -0700 (PDT) X-Received: by 2002:a37:6dc4:: with SMTP id i187-v6mr24668809qkc.34.1533136639075; Wed, 01 Aug 2018 08:17:19 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136638; cv=none; d=google.com; s=arc-20160816; b=fZ6e9m2wxf2vjxG4Px1HH7q/qfcIrMvTKBn27yzcDaG2i4jNKqNyFWaOjSQKlorjJ5 M+LHFm+m3TF0hnTNEz8gFSjYrnZEOwqpLCYOIHIrBZk8azR6YJO/IjB2hLRDJFLzYBo3 E7kHu25iIfpJjQ7wrfxbbkhPvJpz5RPQ0HxVVbDH26QalZe2zDlKFIgQFVXcooW7dV8V /KCjgJC4XwCjFTQXC7pThGs6yD5JkCNGCJ6E9hGRC5CFsGaDRVrm7SzZ71h27D2mzfRM fdVmQ/AGqZwxLpH0BETcosDO43rC19LCq+Pe9ecgEqixik1L6bAl97Hu6HYnHArD7J8g HEjQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=qQSBTnxNlt3eRiLy52Sx1ZjqVOe8sAaRJJ76RsaU+wI=; b=nrWDBwGWk7IVjEj4VCNLE/fhA6SKyVRoMtICb/tN9k7SGmbGSxCV5RwT4XLpFYUBDJ hocxWoSRamd88KL892sUG4p6GLxueHfayJ61Ivgy2NhSTbwVp6M94qTRyFFFkIDoGBOP BYmJlx0t9y7CLjpP4W69Sd43+L9TVvxnLy8kNQKW2G6op1r3QQCwsZUCekVoeIpdO2oj oLmF8dcWSdpmpbt7b2xVoRt7Y/Nn+hedGOFkkKVBaiX8RaPGmqn15usBCVZCJiBduhwZ IdXmH8O2VCei0xueVyFcOZinFMp1T0g0xWQO2x1v+gPkdGa0bf1j0uxn08K3FUkjDo6l 0hMg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=n5fdTS8N; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id m2-v6sor8310093qkc.110.2018.08.01.08.17.18 for (Google Transport Security); Wed, 01 Aug 2018 08:17:18 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=n5fdTS8N; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=qQSBTnxNlt3eRiLy52Sx1ZjqVOe8sAaRJJ76RsaU+wI=; b=n5fdTS8NXfiqD2ySdaioTvUNdBeWM6cjtukq1hyhRExh4EE8NRdJibsu6Q/KiOgf4+ OxXihVNl26A/AWdDKgGM2uUnsBy2c1WMZVqRtPIXc4atVPbOcFavUnc8+bBZMxbeSJHB wdAbq2ANOfQVTybHNvZlkxPK2WRP15jt2sF1M/8bkd95XF9sbmM+TqZ7A3s8vhoNnkKe RfaQbBuxTEpLp+WSMj7prKcc3XfPzavGQ7jkWD7ZoSfmoHFNic59uSyRgms3rcMwLzkB TeQ/FFNrKMKQ/HMkITDDjIuW0tgGmLEMZtT794jdkojm9IPrQ/UCW1GMnDsJyFfjZ1EZ 2mlA== X-Google-Smtp-Source: AAOMgpfhDNjjTQtUyqBnXtnXWjU+Ztd897CT7fN2dMQMd160fkUHSnaJlzBqaUjlRvCf6x/5zMPzNg== X-Received: by 2002:a37:424a:: with SMTP id p71-v6mr24398812qka.100.1533136638474; Wed, 01 Aug 2018 08:17:18 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id c93-v6sm17611112qkh.90.2018.08.01.08.17.16 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:17 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 2/9] mm: workingset: tell cache transitions from workingset thrashing Date: Wed, 1 Aug 2018 11:19:51 -0400 Message-Id: <20180801151958.32590-3-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Refaults happen during transitions between workingsets as well as in-place thrashing. Knowing the difference between the two has a range of applications, including measuring the impact of memory shortage on the system performance, as well as the ability to smarter balance pressure between the filesystem cache and the swap-backed workingset. During workingset transitions, inactive cache refaults and pushes out established active cache. When that active cache isn't stale, however, and also ends up refaulting, that's bonafide thrashing. Introduce a new page flag that tells on eviction whether the page has been active or not in its lifetime. This bit is then stored in the shadow entry, to classify refaults as transitioning or thrashing. How many page->flags does this leave us with on 32-bit? 20 bits are always page flags 21 if you have an MMU 23 with the zone bits for DMA, Normal, HighMem, Movable 29 with the sparsemem section bits 30 if PAE is enabled 31 with this patch. So on 32-bit PAE, that leaves 1 bit for distinguishing two NUMA nodes. If that's not enough, the system can switch to discontigmem and re-gain the 6 or 7 sparsemem section bits. Signed-off-by: Johannes Weiner --- include/linux/mmzone.h | 1 + include/linux/page-flags.h | 5 +- include/linux/swap.h | 2 +- include/trace/events/mmflags.h | 1 + mm/filemap.c | 9 ++-- mm/huge_memory.c | 1 + mm/memcontrol.c | 2 + mm/migrate.c | 2 + mm/swap_state.c | 1 + mm/vmscan.c | 1 + mm/vmstat.c | 1 + mm/workingset.c | 95 ++++++++++++++++++++++------------ 12 files changed, 79 insertions(+), 42 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 32699b2dc52a..6af87946d241 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -163,6 +163,7 @@ enum node_stat_item { NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */ WORKINGSET_REFAULT, WORKINGSET_ACTIVATE, + WORKINGSET_RESTORE, WORKINGSET_NODERECLAIM, NR_ANON_MAPPED, /* Mapped anonymous pages */ NR_FILE_MAPPED, /* pagecache pages mapped into pagetables. diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index e34a27727b9a..7af1c3c15d8e 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -69,13 +69,14 @@ */ enum pageflags { PG_locked, /* Page is locked. Don't touch. */ - PG_error, PG_referenced, PG_uptodate, PG_dirty, PG_lru, PG_active, + PG_workingset, PG_waiters, /* Page has waiters, check its waitqueue. Must be bit #7 and in the same byte as "PG_locked" */ + PG_error, PG_slab, PG_owner_priv_1, /* Owner use. If pagecache, fs may use*/ PG_arch_1, @@ -280,6 +281,8 @@ PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD) PAGEFLAG(LRU, lru, PF_HEAD) __CLEARPAGEFLAG(LRU, lru, PF_HEAD) PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD) TESTCLEARFLAG(Active, active, PF_HEAD) +PAGEFLAG(Workingset, workingset, PF_HEAD) + TESTCLEARFLAG(Workingset, workingset, PF_HEAD) __PAGEFLAG(Slab, slab, PF_NO_TAIL) __PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL) PAGEFLAG(Checked, checked, PF_NO_COMPOUND) /* Used by some filesystems */ diff --git a/include/linux/swap.h b/include/linux/swap.h index 2417d288e016..d8c47dcdec6f 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -296,7 +296,7 @@ struct vma_swap_readahead { /* linux/mm/workingset.c */ void *workingset_eviction(struct address_space *mapping, struct page *page); -bool workingset_refault(void *shadow); +void workingset_refault(struct page *page, void *shadow); void workingset_activation(struct page *page); /* Do not use directly, use workingset_lookup_update */ diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h index a81cffb76d89..a1675d43777e 100644 --- a/include/trace/events/mmflags.h +++ b/include/trace/events/mmflags.h @@ -88,6 +88,7 @@ {1UL << PG_dirty, "dirty" }, \ {1UL << PG_lru, "lru" }, \ {1UL << PG_active, "active" }, \ + {1UL << PG_workingset, "workingset" }, \ {1UL << PG_slab, "slab" }, \ {1UL << PG_owner_priv_1, "owner_priv_1" }, \ {1UL << PG_arch_1, "arch_1" }, \ diff --git a/mm/filemap.c b/mm/filemap.c index 0604cb02e6f3..bd36b7226cf4 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -915,12 +915,9 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping, * data from the working set, only to cache data that will * get overwritten with something else, is a waste of memory. */ - if (!(gfp_mask & __GFP_WRITE) && - shadow && workingset_refault(shadow)) { - SetPageActive(page); - workingset_activation(page); - } else - ClearPageActive(page); + WARN_ON_ONCE(PageActive(page)); + if (!(gfp_mask & __GFP_WRITE) && shadow) + workingset_refault(page, shadow); lru_cache_add(page); } return ret; diff --git a/mm/huge_memory.c b/mm/huge_memory.c index b9f3dbd885bd..c67ecf77ea8b 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2370,6 +2370,7 @@ static void __split_huge_page_tail(struct page *head, int tail, (1L << PG_mlocked) | (1L << PG_uptodate) | (1L << PG_active) | + (1L << PG_workingset) | (1L << PG_locked) | (1L << PG_unevictable) | (1L << PG_dirty))); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2bd3df3d101a..c59519d600ea 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5283,6 +5283,8 @@ static int memory_stat_show(struct seq_file *m, void *v) stat[WORKINGSET_REFAULT]); seq_printf(m, "workingset_activate %lu\n", stat[WORKINGSET_ACTIVATE]); + seq_printf(m, "workingset_restore %lu\n", + stat[WORKINGSET_RESTORE]); seq_printf(m, "workingset_nodereclaim %lu\n", stat[WORKINGSET_NODERECLAIM]); diff --git a/mm/migrate.c b/mm/migrate.c index 8c0af0f7cab1..a6a9114e62dc 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -682,6 +682,8 @@ void migrate_page_states(struct page *newpage, struct page *page) SetPageActive(newpage); } else if (TestClearPageUnevictable(page)) SetPageUnevictable(newpage); + if (PageWorkingset(page)) + SetPageWorkingset(newpage); if (PageChecked(page)) SetPageChecked(newpage); if (PageMappedToDisk(page)) diff --git a/mm/swap_state.c b/mm/swap_state.c index 07f9aa2340c3..2721ef8862d1 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -451,6 +451,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, /* * Initiate read into locked page and return. */ + SetPageWorkingset(new_page); lru_cache_add_anon(new_page); *new_page_allocated = true; return new_page; diff --git a/mm/vmscan.c b/mm/vmscan.c index 9270a4370d54..8d1ad48ffbcd 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1976,6 +1976,7 @@ static void shrink_active_list(unsigned long nr_to_scan, } ClearPageActive(page); /* we are de-activating */ + SetPageWorkingset(page); list_add(&page->lru, &l_inactive); } diff --git a/mm/vmstat.c b/mm/vmstat.c index a2b9518980ce..507dc9c01b88 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1145,6 +1145,7 @@ const char * const vmstat_text[] = { "nr_isolated_file", "workingset_refault", "workingset_activate", + "workingset_restore", "workingset_nodereclaim", "nr_anon_pages", "nr_mapped", diff --git a/mm/workingset.c b/mm/workingset.c index 53759a3cf99a..ef6be3d92116 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -121,7 +121,7 @@ * the only thing eating into inactive list space is active pages. * * - * Activating refaulting pages + * Refaulting inactive pages * * All that is known about the active list is that the pages have been * accessed more than once in the past. This means that at any given @@ -134,6 +134,10 @@ * used less frequently than the refaulting page - or even not used at * all anymore. * + * That means if inactive cache is refaulting with a suitable refault + * distance, we assume the cache workingset is transitioning and put + * pressure on the current active list. + * * If this is wrong and demotion kicks in, the pages which are truly * used more frequently will be reactivated while the less frequently * used once will be evicted from memory. @@ -141,6 +145,14 @@ * But if this is right, the stale pages will be pushed out of memory * and the used pages get to stay in cache. * + * Refaulting active pages + * + * If on the other hand the refaulting pages have recently been + * deactivated, it means that the active list is no longer protecting + * actively used cache from reclaim. The cache is NOT transitioning to + * a different workingset; the existing workingset is thrashing in the + * space allocated to the page cache. + * * * Implementation * @@ -156,8 +168,7 @@ */ #define EVICTION_SHIFT (RADIX_TREE_EXCEPTIONAL_ENTRY + \ - NODES_SHIFT + \ - MEM_CGROUP_ID_SHIFT) + 1 + NODES_SHIFT + MEM_CGROUP_ID_SHIFT) #define EVICTION_MASK (~0UL >> EVICTION_SHIFT) /* @@ -170,23 +181,28 @@ */ static unsigned int bucket_order __read_mostly; -static void *pack_shadow(int memcgid, pg_data_t *pgdat, unsigned long eviction) +static void *pack_shadow(int memcgid, pg_data_t *pgdat, unsigned long eviction, + bool workingset) { eviction >>= bucket_order; eviction = (eviction << MEM_CGROUP_ID_SHIFT) | memcgid; eviction = (eviction << NODES_SHIFT) | pgdat->node_id; + eviction = (eviction << 1) | workingset; eviction = (eviction << RADIX_TREE_EXCEPTIONAL_SHIFT); return (void *)(eviction | RADIX_TREE_EXCEPTIONAL_ENTRY); } static void unpack_shadow(void *shadow, int *memcgidp, pg_data_t **pgdat, - unsigned long *evictionp) + unsigned long *evictionp, bool *workingsetp) { unsigned long entry = (unsigned long)shadow; int memcgid, nid; + bool workingset; entry >>= RADIX_TREE_EXCEPTIONAL_SHIFT; + workingset = entry & 1; + entry >>= 1; nid = entry & ((1UL << NODES_SHIFT) - 1); entry >>= NODES_SHIFT; memcgid = entry & ((1UL << MEM_CGROUP_ID_SHIFT) - 1); @@ -195,6 +211,7 @@ static void unpack_shadow(void *shadow, int *memcgidp, pg_data_t **pgdat, *memcgidp = memcgid; *pgdat = NODE_DATA(nid); *evictionp = entry << bucket_order; + *workingsetp = workingset; } /** @@ -207,8 +224,8 @@ static void unpack_shadow(void *shadow, int *memcgidp, pg_data_t **pgdat, */ void *workingset_eviction(struct address_space *mapping, struct page *page) { - struct mem_cgroup *memcg = page_memcg(page); struct pglist_data *pgdat = page_pgdat(page); + struct mem_cgroup *memcg = page_memcg(page); int memcgid = mem_cgroup_id(memcg); unsigned long eviction; struct lruvec *lruvec; @@ -220,30 +237,30 @@ void *workingset_eviction(struct address_space *mapping, struct page *page) lruvec = mem_cgroup_lruvec(pgdat, memcg); eviction = atomic_long_inc_return(&lruvec->inactive_age); - return pack_shadow(memcgid, pgdat, eviction); + return pack_shadow(memcgid, pgdat, eviction, PageWorkingset(page)); } /** * workingset_refault - evaluate the refault of a previously evicted page + * @page: the freshly allocated replacement page * @shadow: shadow entry of the evicted page * * Calculates and evaluates the refault distance of the previously * evicted page in the context of the node it was allocated in. - * - * Returns %true if the page should be activated, %false otherwise. */ -bool workingset_refault(void *shadow) +void workingset_refault(struct page *page, void *shadow) { unsigned long refault_distance; + struct pglist_data *pgdat; unsigned long active_file; struct mem_cgroup *memcg; unsigned long eviction; struct lruvec *lruvec; unsigned long refault; - struct pglist_data *pgdat; + bool workingset; int memcgid; - unpack_shadow(shadow, &memcgid, &pgdat, &eviction); + unpack_shadow(shadow, &memcgid, &pgdat, &eviction, &workingset); rcu_read_lock(); /* @@ -263,41 +280,51 @@ bool workingset_refault(void *shadow) * configurations instead. */ memcg = mem_cgroup_from_id(memcgid); - if (!mem_cgroup_disabled() && !memcg) { - rcu_read_unlock(); - return false; - } + if (!mem_cgroup_disabled() && !memcg) + goto out; lruvec = mem_cgroup_lruvec(pgdat, memcg); refault = atomic_long_read(&lruvec->inactive_age); active_file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE, MAX_NR_ZONES); /* - * The unsigned subtraction here gives an accurate distance - * across inactive_age overflows in most cases. + * Calculate the refault distance * - * There is a special case: usually, shadow entries have a - * short lifetime and are either refaulted or reclaimed along - * with the inode before they get too old. But it is not - * impossible for the inactive_age to lap a shadow entry in - * the field, which can then can result in a false small - * refault distance, leading to a false activation should this - * old entry actually refault again. However, earlier kernels - * used to deactivate unconditionally with *every* reclaim - * invocation for the longest time, so the occasional - * inappropriate activation leading to pressure on the active - * list is not a problem. + * The unsigned subtraction here gives an accurate distance + * across inactive_age overflows in most cases. There is a + * special case: usually, shadow entries have a short lifetime + * and are either refaulted or reclaimed along with the inode + * before they get too old. But it is not impossible for the + * inactive_age to lap a shadow entry in the field, which can + * then can result in a false small refault distance, leading + * to a false activation should this old entry actually + * refault again. However, earlier kernels used to deactivate + * unconditionally with *every* reclaim invocation for the + * longest time, so the occasional inappropriate activation + * leading to pressure on the active list is not a problem. */ refault_distance = (refault - eviction) & EVICTION_MASK; inc_lruvec_state(lruvec, WORKINGSET_REFAULT); - if (refault_distance <= active_file) { - inc_lruvec_state(lruvec, WORKINGSET_ACTIVATE); - rcu_read_unlock(); - return true; + /* + * Compare the distance to the existing workingset size. We + * don't act on pages that couldn't stay resident even if all + * the memory was available to the page cache. + */ + if (refault_distance > active_file) + goto out; + + SetPageActive(page); + atomic_long_inc(&lruvec->inactive_age); + inc_lruvec_state(lruvec, WORKINGSET_ACTIVATE); + + /* Page was active prior to eviction */ + if (workingset) { + SetPageWorkingset(page); + inc_lruvec_state(lruvec, WORKINGSET_RESTORE); } +out: rcu_read_unlock(); - return false; } /** From patchwork Wed Aug 1 15:19:52 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552461 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 28B8A15E9 for ; Wed, 1 Aug 2018 15:17:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 197932B5AF for ; Wed, 1 Aug 2018 15:17:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0D87F2B703; Wed, 1 Aug 2018 15:17:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 51C8D2B5AF for ; Wed, 1 Aug 2018 15:17:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9142F6B027A; Wed, 1 Aug 2018 11:17:22 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 7FB266B027C; Wed, 1 Aug 2018 11:17:22 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 677746B027D; Wed, 1 Aug 2018 11:17:22 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qk0-f198.google.com (mail-qk0-f198.google.com [209.85.220.198]) by kanga.kvack.org (Postfix) with ESMTP id 36E076B027A for ; Wed, 1 Aug 2018 11:17:22 -0400 (EDT) Received: by mail-qk0-f198.google.com with SMTP id c27-v6so17247154qkj.3 for ; Wed, 01 Aug 2018 08:17:22 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=yu9UdCtaoT51hJzI6OxnWMzNlhzbw5nOYEshpoGdmog=; b=CqYQIL8hZZfZKVj/91Qpt1H2VBjFTCej2RVFCDGb3niYvXLZHn0hl46fbr1i5GCqvQ DNKi1Q7LubUwzK4wiehagDf0oBn/4p79HJK9DwziPk1WNEEZTvMerR/1I3GeIo1YSOS4 PPONejSn2ropu8WlseL2cm9FOgZUMU1rpTgBay5epwLM7UamsnhRnrUKZD2VIHLUFgxg oPHf1K5goaLWIN22jyY4+FQvr9fJd25stL0lPZEbPmRsZzxibrdlnOlGGwRIlo1jgTQm X5/D25c+Kzn7PpT6EOGBrdD/uSncFae6kB2vfQtyfaBRDI2DzIbBDoISzqDAar7Nzu7t cnSA== X-Gm-Message-State: AOUpUlGxSsVltakZZ1rHB3gNKA3uWlCLxrI6GZxHFzvVev1V9W0RAzmH du7Yr4qvM8F0uv6ZGM8ziv77qtozQzAvQiyFzbZg4ogZRv5fIMc5Pt5GJ1pkhHk18bmLabjyejR 2KXAwO7NaoQyfQaHPr5Op049wua68PD/Gj3LDOhScwUMn9XTywkq57Uv9xE4iix7WVyqbADghrL 62WnjGCXD6aUGIDCnclDJAMGFqvSwEiT/Jsjai25lxdVv3eSHfGW3aAa0m5wYuU0Wljf7+U39QA uintR/NMRCo4PdMHTT6T1YMJNCa1LnRx/wyfVDWa8MtAFcvOBGPGc1dvUG9RNOLztgaHIClnb/L amxs+eFJr25rAnq/VEknNy3D4FaHL6zVGjxjF/1+mfGUmF22gKvrWwTpdlnuqq09ABQwTDETP6v t X-Received: by 2002:a37:cc8d:: with SMTP id n13-v6mr25117113qkl.223.1533136641975; Wed, 01 Aug 2018 08:17:21 -0700 (PDT) X-Received: by 2002:a37:cc8d:: with SMTP id n13-v6mr25117048qkl.223.1533136641206; Wed, 01 Aug 2018 08:17:21 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136641; cv=none; d=google.com; s=arc-20160816; b=IZcYf4sm3T8PQociSIbxdkGIWPjIqreggfk4ny2T0EVZFAjzH/bxkMB55Oco7wy8g5 DZOf+8wfnjqNM4Zw4I7vDJ6G4GnjFDB/UfZJEREb1+QnEopUrdhpJq+sR/IM7iS9d5+P LuRrMdbYDOkz44DToVmyc+HC+IrpCeI8St2WnQpQIXXY8ufGwnsYYEASxNK2VrPYZLb5 ds901CT/pZdjLIj5/w+RQPF2DPosDJvsmvxecN9Xh790k/GaK5YFR4aLDqTOvN296C9h 2eJa38g2QyDTQqKwImut3YFvYEC9uHH+uM31hbqz8xkJSmuXvqBG8q1DQfX+TE7KeVNl CqUg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=yu9UdCtaoT51hJzI6OxnWMzNlhzbw5nOYEshpoGdmog=; b=0UkBtmKsIa6/bFcF1W+uiaMt2SNIcIt33ODxTvtRqgIO4ZUlZ+BvUYgV6XJc1Ii04x XRgtV7MgXhtANv2xmKopSPoOgVhJwcaIZC45gnqXpdyEBwN6mtcDPf1VfamrlxOxBCgS /zi68Lgq1qkHYl//UOqa+mTaot6PqOpYUeE/1Lp38BPDIKdRDBNdVDfCJqZKCvEKsjRT WYKYmr1RuUVtp4L1X6zFx6QL9Yyl8xL44+KZbfHb68R19/1eABf1FPHp4ZQjNk9LIw+W DTY8VU6UjE4nGykrP0gRMXVkaZGFhGwQdzM8wYEduyGaktJEb25fzhnatgzTnEwJgtjo 9toQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=nU6nW8aD; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id c5-v6sor7884032qvn.79.2018.08.01.08.17.21 for (Google Transport Security); Wed, 01 Aug 2018 08:17:21 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=nU6nW8aD; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=yu9UdCtaoT51hJzI6OxnWMzNlhzbw5nOYEshpoGdmog=; b=nU6nW8aDdAj9ucMbCPQn1mbv/ysQnX3z6H7LWSDwFF1stR3Qyduqrk//UnYBPInyTF iPsLNFLpy0A63l3pkYzxk3ygw11H6zUd8UQHocl75N/IuftWxi21WVJvIJkLdi4PjNL+ cjwW7VDtq+y/njFgGDt0R2d0qw5rxP5lkUy7bFNkDuffOoYMJQGHqoIqnIKDP69un0rX sc7RaGWd4qpIjYNt1eachJPf48l5IO21txIkRAsorLweu+NuOtRvNfK/RpV9L0dSrG9V kawmB9mzco0i5athlAaWMOsR7nPiu0/wNpmcdjNrDzTkRRIZz3YBq3YE6rCA335/dDEc +pOg== X-Google-Smtp-Source: AAOMgpdpiO1+5dTenI5rkqN6KooOzzXG9pjb8bbE8lJDgK0SL3xf6THg406jAEBXkRDzv/S1D8Y9Yg== X-Received: by 2002:a0c:b888:: with SMTP id y8-v6mr23729437qvf.203.1533136640724; Wed, 01 Aug 2018 08:17:20 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id c93-v6sm17611210qkh.90.2018.08.01.08.17.19 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:19 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 3/9] delayacct: track delays from thrashing cache pages Date: Wed, 1 Aug 2018 11:19:52 -0400 Message-Id: <20180801151958.32590-4-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Delay accounting already measures the time a task spends in direct reclaim and waiting for swapin, but in low memory situations tasks spend can spend a significant amount of their time waiting on thrashing page cache. This isn't tracked right now. To know the full impact of memory contention on an individual task, measure the delay when waiting for a recently evicted active cache page to read back into memory. Also update tools/accounting/getdelays.c: [hannes@computer accounting]$ sudo ./getdelays -d -p 1 print delayacct stats ON PID 1 CPU count real total virtual total delay total delay average 50318 745000000 847346785 400533713 0.008ms IO count delay total delay average 435 122601218 0ms SWAP count delay total delay average 0 0 0ms RECLAIM count delay total delay average 0 0 0ms THRASHING count delay total delay average 19 12621439 0ms Signed-off-by: Johannes Weiner --- include/linux/delayacct.h | 23 +++++++++++++++++++++++ include/uapi/linux/taskstats.h | 6 +++++- kernel/delayacct.c | 15 +++++++++++++++ mm/filemap.c | 11 +++++++++++ tools/accounting/getdelays.c | 8 +++++++- 5 files changed, 61 insertions(+), 2 deletions(-) diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h index 5e335b6203f4..d3e75b3ba487 100644 --- a/include/linux/delayacct.h +++ b/include/linux/delayacct.h @@ -57,7 +57,12 @@ struct task_delay_info { u64 freepages_start; u64 freepages_delay; /* wait for memory reclaim */ + + u64 thrashing_start; + u64 thrashing_delay; /* wait for thrashing page */ + u32 freepages_count; /* total count of memory reclaim */ + u32 thrashing_count; /* total count of thrash waits */ }; #endif @@ -76,6 +81,8 @@ extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *); extern __u64 __delayacct_blkio_ticks(struct task_struct *); extern void __delayacct_freepages_start(void); extern void __delayacct_freepages_end(void); +extern void __delayacct_thrashing_start(void); +extern void __delayacct_thrashing_end(void); static inline int delayacct_is_task_waiting_on_io(struct task_struct *p) { @@ -156,6 +163,18 @@ static inline void delayacct_freepages_end(void) __delayacct_freepages_end(); } +static inline void delayacct_thrashing_start(void) +{ + if (current->delays) + __delayacct_thrashing_start(); +} + +static inline void delayacct_thrashing_end(void) +{ + if (current->delays) + __delayacct_thrashing_end(); +} + #else static inline void delayacct_set_flag(int flag) {} @@ -182,6 +201,10 @@ static inline void delayacct_freepages_start(void) {} static inline void delayacct_freepages_end(void) {} +static inline void delayacct_thrashing_start(void) +{} +static inline void delayacct_thrashing_end(void) +{} #endif /* CONFIG_TASK_DELAY_ACCT */ diff --git a/include/uapi/linux/taskstats.h b/include/uapi/linux/taskstats.h index b7aa7bb2349f..5e8ca16a9079 100644 --- a/include/uapi/linux/taskstats.h +++ b/include/uapi/linux/taskstats.h @@ -34,7 +34,7 @@ */ -#define TASKSTATS_VERSION 8 +#define TASKSTATS_VERSION 9 #define TS_COMM_LEN 32 /* should be >= TASK_COMM_LEN * in linux/sched.h */ @@ -164,6 +164,10 @@ struct taskstats { /* Delay waiting for memory reclaim */ __u64 freepages_count; __u64 freepages_delay_total; + + /* Delay waiting for thrashing page */ + __u64 thrashing_count; + __u64 thrashing_delay_total; }; diff --git a/kernel/delayacct.c b/kernel/delayacct.c index e2764d767f18..02ba745c448d 100644 --- a/kernel/delayacct.c +++ b/kernel/delayacct.c @@ -134,9 +134,12 @@ int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) d->swapin_delay_total = (tmp < d->swapin_delay_total) ? 0 : tmp; tmp = d->freepages_delay_total + tsk->delays->freepages_delay; d->freepages_delay_total = (tmp < d->freepages_delay_total) ? 0 : tmp; + tmp = d->thrashing_delay_total + tsk->delays->thrashing_delay; + d->thrashing_delay_total = (tmp < d->thrashing_delay_total) ? 0 : tmp; d->blkio_count += tsk->delays->blkio_count; d->swapin_count += tsk->delays->swapin_count; d->freepages_count += tsk->delays->freepages_count; + d->thrashing_count += tsk->delays->thrashing_count; spin_unlock_irqrestore(&tsk->delays->lock, flags); return 0; @@ -168,3 +171,15 @@ void __delayacct_freepages_end(void) ¤t->delays->freepages_count); } +void __delayacct_thrashing_start(void) +{ + current->delays->thrashing_start = ktime_get_ns(); +} + +void __delayacct_thrashing_end(void) +{ + delayacct_end(¤t->delays->lock, + ¤t->delays->thrashing_start, + ¤t->delays->thrashing_delay, + ¤t->delays->thrashing_count); +} diff --git a/mm/filemap.c b/mm/filemap.c index bd36b7226cf4..e49961e13dd9 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -36,6 +36,7 @@ #include #include #include +#include #include "internal.h" #define CREATE_TRACE_POINTS @@ -1073,8 +1074,15 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q, { struct wait_page_queue wait_page; wait_queue_entry_t *wait = &wait_page.wait; + bool thrashing = false; int ret = 0; + if (bit_nr == PG_locked && !PageSwapBacked(page) && + !PageUptodate(page) && PageWorkingset(page)) { + delayacct_thrashing_start(); + thrashing = true; + } + init_wait(wait); wait->flags = lock ? WQ_FLAG_EXCLUSIVE : 0; wait->func = wake_page_function; @@ -1113,6 +1121,9 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q, finish_wait(q, wait); + if (thrashing) + delayacct_thrashing_end(); + /* * A signal could leave PageWaiters set. Clearing it here if * !waitqueue_active would be possible (by open-coding finish_wait), diff --git a/tools/accounting/getdelays.c b/tools/accounting/getdelays.c index 9f420d98b5fb..8cb504d30384 100644 --- a/tools/accounting/getdelays.c +++ b/tools/accounting/getdelays.c @@ -203,6 +203,8 @@ static void print_delayacct(struct taskstats *t) "SWAP %15s%15s%15s\n" " %15llu%15llu%15llums\n" "RECLAIM %12s%15s%15s\n" + " %15llu%15llu%15llums\n" + "THRASHING%12s%15s%15s\n" " %15llu%15llu%15llums\n", "count", "real total", "virtual total", "delay total", "delay average", @@ -222,7 +224,11 @@ static void print_delayacct(struct taskstats *t) "count", "delay total", "delay average", (unsigned long long)t->freepages_count, (unsigned long long)t->freepages_delay_total, - average_ms(t->freepages_delay_total, t->freepages_count)); + average_ms(t->freepages_delay_total, t->freepages_count), + "count", "delay total", "delay average", + (unsigned long long)t->thrashing_count, + (unsigned long long)t->thrashing_delay_total, + average_ms(t->thrashing_delay_total, t->thrashing_count)); } static void task_context_switch_counts(struct taskstats *t) From patchwork Wed Aug 1 15:19:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552463 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8BC6F14E2 for ; Wed, 1 Aug 2018 15:17:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7CBDB2B5AF for ; Wed, 1 Aug 2018 15:17:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 709FE2B703; Wed, 1 Aug 2018 15:17:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C17392B5AF for ; Wed, 1 Aug 2018 15:17:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6C62F6B027C; Wed, 1 Aug 2018 11:17:29 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 676156B027E; Wed, 1 Aug 2018 11:17:29 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 53C946B027F; Wed, 1 Aug 2018 11:17:29 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qt0-f200.google.com (mail-qt0-f200.google.com [209.85.216.200]) by kanga.kvack.org (Postfix) with ESMTP id 24C7B6B027C for ; Wed, 1 Aug 2018 11:17:29 -0400 (EDT) Received: by mail-qt0-f200.google.com with SMTP id o6-v6so16092787qtp.15 for ; Wed, 01 Aug 2018 08:17:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=eqQ2drM6ZB7t7xA4Vh6Us/fahKGTELhOpcUpFPV0E1Y=; b=OlHFvPmzdlF1LjPEdUEJ+V7Jvxfd3D3sXkfnCpaniTI0RMEaVPMD9hgkyJ/6a3y7hD 902ewCBd0eiQXMEb+EaJ0p93g2JslFf2NfkmbSoK8DxfJ3yao3snioXrJKmMCei5KlKt o3AReHNE3Vptwh+nMcsTrKUDSUEevdY0TkIalOez200qF+gCe1dRsoHDNxb51l2+CSs3 lqHvCdK+cZCdyeKXjzBXnziiLgbNKoBGDrCT8QTX0fYkX2GwGepct50BA4RH+Eu0ojP5 bkDMBIb16EAeIAp9BNMSVolNDLVAdHygHISRjnN70ilzYqJaCOXgc0YwOFCp1q0xQ7kD yg9g== X-Gm-Message-State: AOUpUlGKNeyaucEq5XA4Smb3k8eXe+aDB3Z8t4hcAxIPR18jSRnYpvtY keLo5wp6s4nSontRoPo3tkvNv6bwUe436iR0RariZ25ELK5qAqzn6A8gtH5HwdjinW9uVP3mgRH y+4ry+KaHdZ+604LaqaDfWKmkGzCTLcUjLkogNz6W6cinfVmR12Lbilo5oI2p0phQ4hbnO2b596 6G36rG21sOFBlz+WEjLvLylLammGjc1FFkcs911ylSR4dOMaQMs1qjipG3YOirKzmmglQnkEXY1 4JRWoEFnFpfy2jkaZw64ZOsascpLfzeE9Ay8rROneHPww/B2uR8z1RB816ehskj/z2a5pJtIiKL XLYe8XdtajpcaK4u1NgyeykR4GmCRWrMKxaQXbfAMXJmDOSDU6ReNxr3jU2RXgJBu9IM9nw94/4 p X-Received: by 2002:a0c:8d8e:: with SMTP id t14-v6mr23895562qvb.32.1533136648913; Wed, 01 Aug 2018 08:17:28 -0700 (PDT) X-Received: by 2002:a0c:8d8e:: with SMTP id t14-v6mr23895506qvb.32.1533136648200; Wed, 01 Aug 2018 08:17:28 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136648; cv=none; d=google.com; s=arc-20160816; b=oZV9/yO2g/C4WJHx/lKJhHF0aHNy/I8bn3Fqpx5VxZUgAIfsc+B4I7rDXyxVG2b8mJ YDKdFb+Kv4aFEKwihZhOZrPPHDQeXMvdm49QnuLwO0JPxECbtvtqYOcTABqviqbP34lT puFfp/wCQpPrIHYihmP9acki9tcikvfO0BANkawvkY+tcYEgl90bEZgXB7AMdWbdfF5Z RLbhGlghyQNvBs5EfxtiAby0M/77pNNaPMh1LCJPK1gxhyuRPoBVMH6XaXyjA5Gu862k EaTAW7GpHy+97sFLbUx6yqnECuww+AJczyTJpS196MSmyIbtdUEuI5MOD61nOORPFZeB /3bw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=eqQ2drM6ZB7t7xA4Vh6Us/fahKGTELhOpcUpFPV0E1Y=; b=LfLZGv216ZuOI9lDzwGmtQ3q0ct0QAlOteLsIttgbmYPTH/hAy5jy3SGEmEGNOrj4K KYeQ++Zssh5ZMKl5U3iNhchj/XrIb1U6hTiGzH3hLLLZPVlgAehD61XOlJGEHmwSSwZe +dM/Yg0lssoYI+abXgaDnVBOcJZCSk1CFaA6mCC9+5wER1RH2TuMgvIxjMAKVkrYi36H RrY6LPRIkQozIEyXqL7AagWzIDto2keZzOQCT+5DjdYlhXOrBPQaPNMg4WvBmzB3KakH Kln2ibuNIhHQw0rgJWz37mNq7nocMcCKwG+US12vAmfuGHu2J8ODmYjSsUcswQtHs6mU InkQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=wuHK9XyX; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id e10-v6sor7882843qvd.60.2018.08.01.08.17.28 for (Google Transport Security); Wed, 01 Aug 2018 08:17:28 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=wuHK9XyX; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=eqQ2drM6ZB7t7xA4Vh6Us/fahKGTELhOpcUpFPV0E1Y=; b=wuHK9XyXw0rF+Tp2cArx0YiZqM/GjpVtqcyTSrQeYiIS+B02zaDa+3gDsB8r9chs3T 6wcThnIY0N8pzjRHhlNIQmTU5fh8GLb1Fob9wXWMv6gFP3uQOPlmNiGg2Qz9i9fA5lkb ZPH7f5zg6kA7DgSYXrtNJpKGKXGNX+Z6D+ZdxZKzPFWjB+ggK2J+dnxyxU7IUO0ZxL5+ 2puJqTqNlCwmu7rM/O+vUSEyll0576DLkwWzoaTZmgg3Uk2/ZhM9cvbgvz7MtV3Dubji 3c2eic5pUxlRK8eO79t1PVgcoesY4Tit5dLqNm8JpVfd6pV/ndmwAc89/ZZkZzj9+HRB tgkw== X-Google-Smtp-Source: AAOMgpfdE+g17VHbSJNxFYjTtyP1v2VW2n2tTjC8/WU1h5l37pndW5+lVrNduKVKQhqkbfXA7cAD3A== X-Received: by 2002:a0c:fa4e:: with SMTP id k14-v6mr23408603qvo.35.1533136647891; Wed, 01 Aug 2018 08:17:27 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id v4-v6sm11040590qth.23.2018.08.01.08.17.26 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:26 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 4/9] sched: loadavg: consolidate LOAD_INT, LOAD_FRAC, CALC_LOAD Date: Wed, 1 Aug 2018 11:19:53 -0400 Message-Id: <20180801151958.32590-5-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP There are several definitions of those functions/macros in places that mess with fixed-point load averages. Provide an official version. Signed-off-by: Johannes Weiner --- .../platforms/cell/cpufreq_spudemand.c | 2 +- arch/powerpc/platforms/cell/spufs/sched.c | 9 +++----- arch/s390/appldata/appldata_os.c | 4 ---- drivers/cpuidle/governors/menu.c | 4 ---- fs/proc/loadavg.c | 3 --- include/linux/sched/loadavg.h | 21 +++++++++++++++---- kernel/debug/kdb/kdb_main.c | 7 +------ kernel/sched/loadavg.c | 15 ------------- 8 files changed, 22 insertions(+), 43 deletions(-) diff --git a/arch/powerpc/platforms/cell/cpufreq_spudemand.c b/arch/powerpc/platforms/cell/cpufreq_spudemand.c index 882944c36ef5..5d8e8b6bb1cc 100644 --- a/arch/powerpc/platforms/cell/cpufreq_spudemand.c +++ b/arch/powerpc/platforms/cell/cpufreq_spudemand.c @@ -49,7 +49,7 @@ static int calc_freq(struct spu_gov_info_struct *info) cpu = info->policy->cpu; busy_spus = atomic_read(&cbe_spu_info[cpu_to_node(cpu)].busy_spus); - CALC_LOAD(info->busy_spus, EXP, busy_spus * FIXED_1); + info->busy_spus = calc_load(info->busy_spus, EXP, busy_spus * FIXED_1); pr_debug("cpu %d: busy_spus=%d, info->busy_spus=%ld\n", cpu, busy_spus, info->busy_spus); diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c index ccc421503363..70101510b19d 100644 --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -987,9 +987,9 @@ static void spu_calc_load(void) unsigned long active_tasks; /* fixed-point */ active_tasks = count_active_contexts() * FIXED_1; - CALC_LOAD(spu_avenrun[0], EXP_1, active_tasks); - CALC_LOAD(spu_avenrun[1], EXP_5, active_tasks); - CALC_LOAD(spu_avenrun[2], EXP_15, active_tasks); + spu_avenrun[0] = calc_load(spu_avenrun[0], EXP_1, active_tasks); + spu_avenrun[1] = calc_load(spu_avenrun[1], EXP_5, active_tasks); + spu_avenrun[2] = calc_load(spu_avenrun[2], EXP_15, active_tasks); } static void spusched_wake(struct timer_list *unused) @@ -1071,9 +1071,6 @@ void spuctx_switch_state(struct spu_context *ctx, } } -#define LOAD_INT(x) ((x) >> FSHIFT) -#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) - static int show_spu_loadavg(struct seq_file *s, void *private) { int a, b, c; diff --git a/arch/s390/appldata/appldata_os.c b/arch/s390/appldata/appldata_os.c index 433a994b1a89..54f375627532 100644 --- a/arch/s390/appldata/appldata_os.c +++ b/arch/s390/appldata/appldata_os.c @@ -25,10 +25,6 @@ #include "appldata.h" - -#define LOAD_INT(x) ((x) >> FSHIFT) -#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) - /* * OS data * diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 1bfe03ceb236..3738b670df7a 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -133,10 +133,6 @@ struct menu_device { int interval_ptr; }; - -#define LOAD_INT(x) ((x) >> FSHIFT) -#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) - static inline int get_loadavg(unsigned long load) { return LOAD_INT(load) * 10 + LOAD_FRAC(load) / 10; diff --git a/fs/proc/loadavg.c b/fs/proc/loadavg.c index b572cc865b92..8bee50a97c0f 100644 --- a/fs/proc/loadavg.c +++ b/fs/proc/loadavg.c @@ -10,9 +10,6 @@ #include #include -#define LOAD_INT(x) ((x) >> FSHIFT) -#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) - static int loadavg_proc_show(struct seq_file *m, void *v) { unsigned long avnrun[3]; diff --git a/include/linux/sched/loadavg.h b/include/linux/sched/loadavg.h index 80bc84ba5d2a..cc9cc62bb1f8 100644 --- a/include/linux/sched/loadavg.h +++ b/include/linux/sched/loadavg.h @@ -22,10 +22,23 @@ extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); #define EXP_5 2014 /* 1/exp(5sec/5min) */ #define EXP_15 2037 /* 1/exp(5sec/15min) */ -#define CALC_LOAD(load,exp,n) \ - load *= exp; \ - load += n*(FIXED_1-exp); \ - load >>= FSHIFT; +/* + * a1 = a0 * e + a * (1 - e) + */ +static inline unsigned long +calc_load(unsigned long load, unsigned long exp, unsigned long active) +{ + unsigned long newload; + + newload = load * exp + active * (FIXED_1 - exp); + if (active >= load) + newload += FIXED_1-1; + + return newload / FIXED_1; +} + +#define LOAD_INT(x) ((x) >> FSHIFT) +#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) extern void calc_global_load(unsigned long ticks); diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index e405677ee08d..a8f5aca5eb5e 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -2556,16 +2556,11 @@ static int kdb_summary(int argc, const char **argv) } kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60); - /* lifted from fs/proc/proc_misc.c::loadavg_read_proc() */ - -#define LOAD_INT(x) ((x) >> FSHIFT) -#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) kdb_printf("load avg %ld.%02ld %ld.%02ld %ld.%02ld\n", LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]), LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]), LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2])); -#undef LOAD_INT -#undef LOAD_FRAC + /* Display in kilobytes */ #define K(x) ((x) << (PAGE_SHIFT - 10)) kdb_printf("\nMemTotal: %8lu kB\nMemFree: %8lu kB\n" diff --git a/kernel/sched/loadavg.c b/kernel/sched/loadavg.c index a171c1258109..54fbdfb2d86c 100644 --- a/kernel/sched/loadavg.c +++ b/kernel/sched/loadavg.c @@ -91,21 +91,6 @@ long calc_load_fold_active(struct rq *this_rq, long adjust) return delta; } -/* - * a1 = a0 * e + a * (1 - e) - */ -static unsigned long -calc_load(unsigned long load, unsigned long exp, unsigned long active) -{ - unsigned long newload; - - newload = load * exp + active * (FIXED_1 - exp); - if (active >= load) - newload += FIXED_1-1; - - return newload / FIXED_1; -} - #ifdef CONFIG_NO_HZ_COMMON /* * Handle NO_HZ for the global load-average. From patchwork Wed Aug 1 15:19:54 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552465 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C2B6E14E2 for ; Wed, 1 Aug 2018 15:17:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B335E2B5AF for ; Wed, 1 Aug 2018 15:17:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A6F9D2B703; Wed, 1 Aug 2018 15:17:34 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0F59B2B5AF for ; Wed, 1 Aug 2018 15:17:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 58C9F6B027E; Wed, 1 Aug 2018 11:17:32 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 51F236B0280; Wed, 1 Aug 2018 11:17:32 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 394A16B0281; Wed, 1 Aug 2018 11:17:32 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qt0-f197.google.com (mail-qt0-f197.google.com [209.85.216.197]) by kanga.kvack.org (Postfix) with ESMTP id 063446B027E for ; Wed, 1 Aug 2018 11:17:32 -0400 (EDT) Received: by mail-qt0-f197.google.com with SMTP id i23-v6so16083420qtf.9 for ; Wed, 01 Aug 2018 08:17:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=7HJ/faUwNp70pvtX2vst2/bX0oNS92n5Rlox7XiLwSM=; b=Njg/1A8ljMtlYqg/rhcRWIvpvyGgPevdRDBF80KHJOxOlvtGedBHOnie2Lg/Bm7HvW kZEY3L6i+DUkTC1O0kmBwOVmKyKvXU4k9cgpkrRgeGXIt+8xlBa8tuwBQROh/VYBEmAR /B1yclv4W5jzTeaajas2aqPKss63OehmP4urF4TtNCtSLZuD5pRPv2s43mI9QcAxE+n8 qVs24YlcVQehzqC7rcrWjMQ+qnYh1jAvWpuNKeZyMt8T19p4Qipkup7KQGh9pW97wBCE eSHgJMNfZwA62smVWrxofeeR4t3bxooTPF8STDbb7hio0VgOz7f/1nWdh3NGpuHYkpwn 3zYw== X-Gm-Message-State: AOUpUlHG/VwdVUKB6osqAaKMc2Yeeqapn4smjdmszS+nN0IO7zQktl76 1b7yhxBp5R21hv+itHq6z/FLeX4SyFoTwM+QthAF+5xu2HbhLd05dlfW3JJdnsiW90gya6ufGuA 1egZGkOK44gPSN1MD1L/IJo0g7YX4HkWLuH/6P9Dj6GkqcSdIyyj4/hD4oSj8uswbSQl5ZM327L JM9cvW4DtybzT8jrLMC9ipcAQ2xhzWv0plQO81ziUQjMs0l3JOuhE9Z4WqUVaB8aaDrCyE4Qcb8 LmKIas2mjhC7bzzEzP3oceoqBMmyFsoHY9Lwx24G6oGomWQAf3MGZgdfGCFPiblOlDWmlyD3igK RyRsRbxTw1/izCEmA+7HhBMmr70kCPEu3n57qLVVs21cvAJMVI4fwL16CWj6dnFaaQwk+9PKBYj p X-Received: by 2002:a0c:9915:: with SMTP id h21-v6mr23989241qvd.122.1533136651809; Wed, 01 Aug 2018 08:17:31 -0700 (PDT) X-Received: by 2002:a0c:9915:: with SMTP id h21-v6mr23989122qvd.122.1533136650387; Wed, 01 Aug 2018 08:17:30 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136650; cv=none; d=google.com; s=arc-20160816; b=tLSw+1Fdyht01j2Z2UJCtRZTRjYXN1qSw4QrDDe5FM7oJ4qzhSnvf6ifFR9zADhlFD NgHSIyP6AyX9SB/hLAE91t/F1/kKTFRMhkBhv3JwWRZfhBw+yVKF3k5COlbCwmxi5FVq leiMD9RuIJ0DIsGkyk47NE73qbihPtJ00AMDFG3eZpxnC3Z4GZ/SeEQLxP2fClYmaeK0 CgH5qrATyyFq+1LqG67TRlGIxnnFTVE47GF/qXYwdgGtWX6qvKYOJbB/RCFED9F8xw+l urk0p7mNbHZ5lBX0tWjE8n4qOVlZM5VOmKMUHwBnwhnUbej2odUU8wZy5h0aDOaJdnmF /2JA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=7HJ/faUwNp70pvtX2vst2/bX0oNS92n5Rlox7XiLwSM=; b=fxz7geNxhBuwJy1CeYyExrECfdIrmZaXFJctfVRwf345Ox5APNn9O5cjrRDEjdUvWz 4hw1AiswjL+a20wcpkDWPHWDM0DG4C6oKOkGca+SwZQeAKnUVAbT9nF+rTvm1qqD70Nb mX/9F39owV9rqKbesA42gqQLO2J2xDT0NdHfiwQ0DyFmwysEJq3B8dgGRey8zJeXJ6vA 5ZQ5s8chZ1PtIMJpdkwKgAsnVgTsY965nfZry9Dxy6lj6u9uRMB5PReI3NSLmvXSmdBc KR8WFoQAmAdDvZcPbINVQeQ4BvjNRS7SqwI3R1j2rwuRCGUT4OoA4DCHaJD52linGMoe 8bkQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=DPctK5zf; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id e40-v6sor8241832qte.64.2018.08.01.08.17.30 for (Google Transport Security); Wed, 01 Aug 2018 08:17:30 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=DPctK5zf; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=7HJ/faUwNp70pvtX2vst2/bX0oNS92n5Rlox7XiLwSM=; b=DPctK5zfYaQ0V4YIT0cOc+G2ibXQKwNsexBwhBszDgpcxVUcfrnx9WMrfKc89CpzWh DmYcv1soQq2VwT3zcvMIUKLLXwi7dgDFW2s8ZmC8sqY3YEjrAc6KPhIzyb83bim9RZIL 6EX7rvRwWH3wYHU+3AgXrQlfKub5GgQui0IGNFSIm9y8nAHMSO78eLwT72940dbXZgi4 XxhT6jMElMtHXZAHx8zuyjBtH7w0twHKqHL8aEBHOIMpi92YVD+KXJvpUg+tB50/0v3h 9Fv3op0mXYXYijb0hMh26+uwl4p3E8GNPT3CVKUyxOxO5cr/UjWFRJ3/6TSkO0snLH3s wuYQ== X-Google-Smtp-Source: AAOMgpdbWpoM7qIjETQdOzVbQgH12G2t7WjQg9oaO/HXxSR73Ckh2cPo3WyzbVTfp8SMPQBIG39a5g== X-Received: by 2002:ac8:460b:: with SMTP id p11-v6mr26602836qtn.418.1533136650080; Wed, 01 Aug 2018 08:17:30 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id t11-v6sm14624295qtc.2.2018.08.01.08.17.28 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:29 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 5/9] sched: loadavg: make calc_load_n() public Date: Wed, 1 Aug 2018 11:19:54 -0400 Message-Id: <20180801151958.32590-6-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP It's going to be used in a later patch. Keep the churn separate. Signed-off-by: Johannes Weiner --- include/linux/sched/loadavg.h | 3 + kernel/sched/loadavg.c | 138 +++++++++++++++++----------------- 2 files changed, 72 insertions(+), 69 deletions(-) diff --git a/include/linux/sched/loadavg.h b/include/linux/sched/loadavg.h index cc9cc62bb1f8..4859bea47a7b 100644 --- a/include/linux/sched/loadavg.h +++ b/include/linux/sched/loadavg.h @@ -37,6 +37,9 @@ calc_load(unsigned long load, unsigned long exp, unsigned long active) return newload / FIXED_1; } +extern unsigned long calc_load_n(unsigned long load, unsigned long exp, + unsigned long active, unsigned int n); + #define LOAD_INT(x) ((x) >> FSHIFT) #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) diff --git a/kernel/sched/loadavg.c b/kernel/sched/loadavg.c index 54fbdfb2d86c..28a516575c18 100644 --- a/kernel/sched/loadavg.c +++ b/kernel/sched/loadavg.c @@ -91,6 +91,75 @@ long calc_load_fold_active(struct rq *this_rq, long adjust) return delta; } +/** + * fixed_power_int - compute: x^n, in O(log n) time + * + * @x: base of the power + * @frac_bits: fractional bits of @x + * @n: power to raise @x to. + * + * By exploiting the relation between the definition of the natural power + * function: x^n := x*x*...*x (x multiplied by itself for n times), and + * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i, + * (where: n_i \elem {0, 1}, the binary vector representing n), + * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is + * of course trivially computable in O(log_2 n), the length of our binary + * vector. + */ +static unsigned long +fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n) +{ + unsigned long result = 1UL << frac_bits; + + if (n) { + for (;;) { + if (n & 1) { + result *= x; + result += 1UL << (frac_bits - 1); + result >>= frac_bits; + } + n >>= 1; + if (!n) + break; + x *= x; + x += 1UL << (frac_bits - 1); + x >>= frac_bits; + } + } + + return result; +} + +/* + * a1 = a0 * e + a * (1 - e) + * + * a2 = a1 * e + a * (1 - e) + * = (a0 * e + a * (1 - e)) * e + a * (1 - e) + * = a0 * e^2 + a * (1 - e) * (1 + e) + * + * a3 = a2 * e + a * (1 - e) + * = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e) + * = a0 * e^3 + a * (1 - e) * (1 + e + e^2) + * + * ... + * + * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1] + * = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e) + * = a0 * e^n + a * (1 - e^n) + * + * [1] application of the geometric series: + * + * n 1 - x^(n+1) + * S_n := \Sum x^i = ------------- + * i=0 1 - x + */ +unsigned long +calc_load_n(unsigned long load, unsigned long exp, + unsigned long active, unsigned int n) +{ + return calc_load(load, fixed_power_int(exp, FSHIFT, n), active); +} + #ifdef CONFIG_NO_HZ_COMMON /* * Handle NO_HZ for the global load-average. @@ -210,75 +279,6 @@ static long calc_load_nohz_fold(void) return delta; } -/** - * fixed_power_int - compute: x^n, in O(log n) time - * - * @x: base of the power - * @frac_bits: fractional bits of @x - * @n: power to raise @x to. - * - * By exploiting the relation between the definition of the natural power - * function: x^n := x*x*...*x (x multiplied by itself for n times), and - * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i, - * (where: n_i \elem {0, 1}, the binary vector representing n), - * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is - * of course trivially computable in O(log_2 n), the length of our binary - * vector. - */ -static unsigned long -fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n) -{ - unsigned long result = 1UL << frac_bits; - - if (n) { - for (;;) { - if (n & 1) { - result *= x; - result += 1UL << (frac_bits - 1); - result >>= frac_bits; - } - n >>= 1; - if (!n) - break; - x *= x; - x += 1UL << (frac_bits - 1); - x >>= frac_bits; - } - } - - return result; -} - -/* - * a1 = a0 * e + a * (1 - e) - * - * a2 = a1 * e + a * (1 - e) - * = (a0 * e + a * (1 - e)) * e + a * (1 - e) - * = a0 * e^2 + a * (1 - e) * (1 + e) - * - * a3 = a2 * e + a * (1 - e) - * = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e) - * = a0 * e^3 + a * (1 - e) * (1 + e + e^2) - * - * ... - * - * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1] - * = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e) - * = a0 * e^n + a * (1 - e^n) - * - * [1] application of the geometric series: - * - * n 1 - x^(n+1) - * S_n := \Sum x^i = ------------- - * i=0 1 - x - */ -static unsigned long -calc_load_n(unsigned long load, unsigned long exp, - unsigned long active, unsigned int n) -{ - return calc_load(load, fixed_power_int(exp, FSHIFT, n), active); -} - /* * NO_HZ can leave us missing all per-CPU ticks calling * calc_load_fold_active(), but since a NO_HZ CPU folds its delta into From patchwork Wed Aug 1 15:19:55 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552467 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A1A9415E9 for ; Wed, 1 Aug 2018 15:17:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 92A982B5AF for ; Wed, 1 Aug 2018 15:17:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 868892B703; Wed, 1 Aug 2018 15:17:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E68912B5AF for ; Wed, 1 Aug 2018 15:17:36 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B0B356B0280; Wed, 1 Aug 2018 11:17:33 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id A95D96B0282; Wed, 1 Aug 2018 11:17:33 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 935186B0283; Wed, 1 Aug 2018 11:17:33 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qk0-f197.google.com (mail-qk0-f197.google.com [209.85.220.197]) by kanga.kvack.org (Postfix) with ESMTP id 66C4A6B0280 for ; Wed, 1 Aug 2018 11:17:33 -0400 (EDT) Received: by mail-qk0-f197.google.com with SMTP id 99-v6so17243881qkr.14 for ; Wed, 01 Aug 2018 08:17:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=NnxyiouhvZnUSydapW5h/V7JQgsuHd8XHvJ9oMKS3Xk=; b=Vm0WI9LFcm9fZeQDG9HDxY1nu/B4JbLsjwDtmxbodXyKCzo/l7rDzY4g8g6BrmwxlV eGomounb2fFEUNM0oZEW9Hkhx3mikhRUHjOKqspkQTqktwsKVsUkTE+tv/pYjgrkGMJj 2mBvP4nvomFiWIR4Tsinm1IImjjq0pr4WjlLLSX7Z+6qGDgxJKDe/1WP+7A1MYqx8Nal c1qtgRhjOvtgDBVBsVH32oNOEN2M8+brikz4oaQaBnq0PIPoJPcF5S+OPPtdTUTZULxm Cg6XavfoOb/iIedtT4foyV0sbXvdy3lERlazbOi96fDOcUO42vMtxBRwEIHjBv/ozB5C 9drw== X-Gm-Message-State: AOUpUlF9Lroa/MtQRQ8ebfBrE+2MR6X6PTegJKmZel5peiLQqJBuBn2Y REdqJi3bWLhZa4P+5Um+Zz5Uhvbjo6teosHQk07znjVre65ED118+xES7ptBzg7UjkTwhYP7tb3 B2bzjyjznUXy2wZOFzR/CdxQ12iubwpMrq4+OIgOjqataUBd1ZHZNqUR2OfI2CD/AtytCh/ZtLH M7cj+eIy3a6nl7PBud7olGEMIYWalm0RfMsm9BoBC/BXs9UovWLTW9GM+K8fhCsupbob2SgfMgl mVNcTuIAX2imkZWzYscWNr7hxiBSfFmjJdYgNDe+qU25ThszVR6Wo/hLS/NZ5hq68ebbCq09Dcf u3+fIOW+dbhQ9/lPilE2a4eP3vTD7WOfi/jMvpZZoYwn3/voN9ti+ZxiN65yQw3CXCV6aNPU2yW C X-Received: by 2002:a0c:9408:: with SMTP id h8-v6mr23619411qvh.135.1533136653161; Wed, 01 Aug 2018 08:17:33 -0700 (PDT) X-Received: by 2002:a0c:9408:: with SMTP id h8-v6mr23619361qvh.135.1533136652474; Wed, 01 Aug 2018 08:17:32 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136652; cv=none; d=google.com; s=arc-20160816; b=eotjJrTQ0uLus6+IYkpwERbotGI4Ytqlwf3ePP1JEnAZuPr2PKHsWWa2X3bL27kmza gkSYXQW4m6Ung1No0QPaE1FEdIb5Os8wuqpteETsvNtXt4Cb7IM5snXenlyE5JYHdVrq maf7BebOHZTUsaOCecd6u0OVSBs33q+gfXzOEHOGH07+ZheBlBOzlfVEnwNq7A1y/VyX B4A+HTf09WNfJ1HZMGmr66tlm18XyNEcuR2hekpsmVVCp+rKtI92wD0BMkyUtcQpuVkv HZGPx/B44XaalJsw2k2jeeOVpqNDPuzT18rQy7Qj2Ixu60rbUwhqodHxWWUXwN4dgiVr vung== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=NnxyiouhvZnUSydapW5h/V7JQgsuHd8XHvJ9oMKS3Xk=; b=MVx37w7YofaCUgIU3wWCW/Lz0i9uETMll0W4TSkv/YXd6wEa4TpL8RMURJ0rZkg9hz 1Ecj7JnaJgBPQfkzhOnF6elAgyrk+Ey2F82ECIGuYugZ1QaT1g3LNqb5bh96fyzJ3aVL VS63ay+9dPTFAs3gKsN5i4YNViJc6ajdBPEZuWdz8VLFkYVc4nquKwFEk90pPWTPHmAZ 75GLKIAewu/qXAecMxnH6lOMA6EzTUd1qEzTseVvbOauUHk4aIGIHtnDshWs8GdLVlil kU88Gk1b+/4teqkj44oLhk7EpyYvtes/NojFiGzK3TMYjBLcEYKxI4HKRdsUh231hZje Yz3A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=kT802V4g; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id o22-v6sor8425358qka.169.2018.08.01.08.17.32 for (Google Transport Security); Wed, 01 Aug 2018 08:17:32 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=kT802V4g; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=NnxyiouhvZnUSydapW5h/V7JQgsuHd8XHvJ9oMKS3Xk=; b=kT802V4gaqvbzln+f7fYdlx75z3raFvWWaTBt1Ow9JJu+sYDH8AC31h2MpNN+ybowx kWiCmVtbOreLhY2E7Ss/RDFI5q+e71n0rRqALyj7H1GsxqyD90HGeMonuHIcCMH16La9 d0OcbT8ER8TruLjo/js6yfJNamgONc0l0RaEaNrDbELS7WDGUe56gFohc3Wang2B/ils ekHw80UG/aGi4IdbXx4x294G9wbS8PW4DfBlYTJBxpUmYqT5Q3qXQ1Sf6qTCVbJpuAsU uqHWEUJLMkuO0nmka52QhW6d+spDzMj6+dbkZD6t/BbBAvDVb4Q9l+tye6zJkb5XxztA P9rw== X-Google-Smtp-Source: AAOMgpd6XA3VsHPvUpK58x5ONBk2skDpwBhL2vuXnT9tx3uqOGsyoxJ/SijzpC0KWqY+DZB2nZer+A== X-Received: by 2002:a37:dd4e:: with SMTP id n75-v6mr23297165qki.370.1533136652152; Wed, 01 Aug 2018 08:17:32 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id t27-v6sm13257610qkl.11.2018.08.01.08.17.30 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:31 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 6/9] sched: sched.h: make rq locking and clock functions available in stats.h Date: Wed, 1 Aug 2018 11:19:55 -0400 Message-Id: <20180801151958.32590-7-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP kernel/sched/sched.h includes "stats.h" half-way through the file. The next patch introduces users of sched.h's rq locking functions and update_rq_clock() in kernel/sched/stats.h. Move those definitions up in the file so they are available in stats.h. Signed-off-by: Johannes Weiner --- kernel/sched/sched.h | 164 +++++++++++++++++++++---------------------- 1 file changed, 82 insertions(+), 82 deletions(-) diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index cb467c221b15..b8f038497240 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -919,6 +919,8 @@ DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); #define cpu_curr(cpu) (cpu_rq(cpu)->curr) #define raw_rq() raw_cpu_ptr(&runqueues) +extern void update_rq_clock(struct rq *rq); + static inline u64 __rq_clock_broken(struct rq *rq) { return READ_ONCE(rq->clock); @@ -1037,6 +1039,86 @@ static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) #endif } +struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) + __acquires(rq->lock); + +struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) + __acquires(p->pi_lock) + __acquires(rq->lock); + +static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) + __releases(rq->lock) +{ + rq_unpin_lock(rq, rf); + raw_spin_unlock(&rq->lock); +} + +static inline void +task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) + __releases(rq->lock) + __releases(p->pi_lock) +{ + rq_unpin_lock(rq, rf); + raw_spin_unlock(&rq->lock); + raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); +} + +static inline void +rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) + __acquires(rq->lock) +{ + raw_spin_lock_irqsave(&rq->lock, rf->flags); + rq_pin_lock(rq, rf); +} + +static inline void +rq_lock_irq(struct rq *rq, struct rq_flags *rf) + __acquires(rq->lock) +{ + raw_spin_lock_irq(&rq->lock); + rq_pin_lock(rq, rf); +} + +static inline void +rq_lock(struct rq *rq, struct rq_flags *rf) + __acquires(rq->lock) +{ + raw_spin_lock(&rq->lock); + rq_pin_lock(rq, rf); +} + +static inline void +rq_relock(struct rq *rq, struct rq_flags *rf) + __acquires(rq->lock) +{ + raw_spin_lock(&rq->lock); + rq_repin_lock(rq, rf); +} + +static inline void +rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) + __releases(rq->lock) +{ + rq_unpin_lock(rq, rf); + raw_spin_unlock_irqrestore(&rq->lock, rf->flags); +} + +static inline void +rq_unlock_irq(struct rq *rq, struct rq_flags *rf) + __releases(rq->lock) +{ + rq_unpin_lock(rq, rf); + raw_spin_unlock_irq(&rq->lock); +} + +static inline void +rq_unlock(struct rq *rq, struct rq_flags *rf) + __releases(rq->lock) +{ + rq_unpin_lock(rq, rf); + raw_spin_unlock(&rq->lock); +} + #ifdef CONFIG_NUMA enum numa_topology_type { NUMA_DIRECT, @@ -1670,8 +1752,6 @@ static inline void sub_nr_running(struct rq *rq, unsigned count) sched_update_tick_dependency(rq); } -extern void update_rq_clock(struct rq *rq); - extern void activate_task(struct rq *rq, struct task_struct *p, int flags); extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); @@ -1752,86 +1832,6 @@ static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { } static inline void sched_avg_update(struct rq *rq) { } #endif -struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) - __acquires(rq->lock); - -struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) - __acquires(p->pi_lock) - __acquires(rq->lock); - -static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) -{ - rq_unpin_lock(rq, rf); - raw_spin_unlock(&rq->lock); -} - -static inline void -task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) - __releases(rq->lock) - __releases(p->pi_lock) -{ - rq_unpin_lock(rq, rf); - raw_spin_unlock(&rq->lock); - raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); -} - -static inline void -rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) - __acquires(rq->lock) -{ - raw_spin_lock_irqsave(&rq->lock, rf->flags); - rq_pin_lock(rq, rf); -} - -static inline void -rq_lock_irq(struct rq *rq, struct rq_flags *rf) - __acquires(rq->lock) -{ - raw_spin_lock_irq(&rq->lock); - rq_pin_lock(rq, rf); -} - -static inline void -rq_lock(struct rq *rq, struct rq_flags *rf) - __acquires(rq->lock) -{ - raw_spin_lock(&rq->lock); - rq_pin_lock(rq, rf); -} - -static inline void -rq_relock(struct rq *rq, struct rq_flags *rf) - __acquires(rq->lock) -{ - raw_spin_lock(&rq->lock); - rq_repin_lock(rq, rf); -} - -static inline void -rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) -{ - rq_unpin_lock(rq, rf); - raw_spin_unlock_irqrestore(&rq->lock, rf->flags); -} - -static inline void -rq_unlock_irq(struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) -{ - rq_unpin_lock(rq, rf); - raw_spin_unlock_irq(&rq->lock); -} - -static inline void -rq_unlock(struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) -{ - rq_unpin_lock(rq, rf); - raw_spin_unlock(&rq->lock); -} - #ifdef CONFIG_SMP #ifdef CONFIG_PREEMPT From patchwork Wed Aug 1 15:19:56 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552469 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 36D6515E9 for ; Wed, 1 Aug 2018 15:17:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 279132B5AF for ; Wed, 1 Aug 2018 15:17:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1A2EC2B703; Wed, 1 Aug 2018 15:17:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AF1BB2B5AF for ; Wed, 1 Aug 2018 15:17:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B0B976B0282; Wed, 1 Aug 2018 11:17:35 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id A99A76B0284; Wed, 1 Aug 2018 11:17:35 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8254B6B0285; Wed, 1 Aug 2018 11:17:35 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qt0-f199.google.com (mail-qt0-f199.google.com [209.85.216.199]) by kanga.kvack.org (Postfix) with ESMTP id 4E38F6B0282 for ; Wed, 1 Aug 2018 11:17:35 -0400 (EDT) Received: by mail-qt0-f199.google.com with SMTP id l23-v6so16120811qtp.1 for ; Wed, 01 Aug 2018 08:17:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=EOH4yuXU61UFUoCxssnGS0E9pmyAjCBzpOCJhmVNCYY=; b=bbKBXQHa7JyOOloVKs1r0iLecJ69+5mLR1tzxnqCUNH3luiZ93AeCa8roTGUNsTCGc YWwvedrucLhT8UikiwY4sg8yCM0lYwFlAkGXrDYsTJ2IW6HVvQl5zD1EEDQNVZTEhRZL sSudGdX3uSmUik+Y5o9WoiNZrrnttzScX9AiRLYsZOJzZYtwdKTWhR0pQwL06wF48Wj9 cxxRnFcwmD+BokYg/pXjd9a6wx4fAm8/w3GRsHUZXeVDsG7prPNTUq5Rg65KZwCV/I9e skIjf05eFeLjzCtTyDoQQ22YISA33Dg3jDq/LmyqkJQVPnjH8VtY88pK5+2xHsRxVBi+ 2KXw== X-Gm-Message-State: AOUpUlFVEFas8P/kKvt7GdUKhesM7zWi+T4wJMh9GodzHo5t61e6Qxkq 3cevt4o0bYGOGl7Q1NpRoeS1gqd0L6zx2XqMDDR6joaHFeWv+j3Iv2cAm6jxnU28wATQNe7We23 LADMO37KsYY11Jcwsi6IvGG+YACprr8d5MAfxMAohq1R8EvH6yXHbsEaU+dz3B9wGvcL9jyt6WH vs48zb4TFn9o9J+9Wa4OIVtqXRmOi/T02wKPqon3zKsBL6MhUrdCYaYSx/RhAResNYu4hsGHGrN Hlbp7euX66/MsvH8tW6s4X6felPFeaok9THuMSHzJ7CLgtMzLDizrbWWwFrNd4t6sSctPtOydW6 PQuhc0kI+D5HEEflIhIAAaPWyTa/ffqJUGfKLPdtQjsPslSkWeQP0PV9lC5SqGZ2fvz+DGbSbLI E X-Received: by 2002:a0c:c3c6:: with SMTP id p6-v6mr23592692qvi.146.1533136655120; Wed, 01 Aug 2018 08:17:35 -0700 (PDT) X-Received: by 2002:a0c:c3c6:: with SMTP id p6-v6mr23592649qvi.146.1533136654592; Wed, 01 Aug 2018 08:17:34 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136654; cv=none; d=google.com; s=arc-20160816; b=g3y+SUYtIjmwe2AC+odWwP5ZSeyVRogOe/Wzr9vGKBzaihkTRhKvqEQtY5mbF20uYx KFViwSO64hoLDkDI2rEm5QuWD4BWLzcoYRm+rEdJ0UnzuhW4v60M2QNtVWxbB3iToykX B7fAAlFJyuzowZLnxzicO+lYI0JGvfnFL0758tlEHvn4VB6RNPxhWQ3LLpdAzF+8otle fZ4YGw703RXU6RPT9Cn/DcN1sGTNzWxfMOY3mGBZE7tlcL1s41Z70oB1wvVLkJy3p7zc L8Tb7wVmV/sORocST4mfKBLdzuPTBlujzuMe/NDZPVjMeuY2R6CMDYxPlHdBOR835toN 4UAw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=EOH4yuXU61UFUoCxssnGS0E9pmyAjCBzpOCJhmVNCYY=; b=RfP9reDkFKi/OeRinmbXsDdouxFFGm9V7q6jU9fusPwdqzHyTYTguRGbO1Epa5vaso rbmnJUN/SsNNaMapozBoNIVHC4ndTLZyOnYYe2MZ45zeqo2kMmI5CRzNU9ZZgIYtEcEk C9ogCSzkRG/a67BhONc2dfwwRXWuK8epHikWpl45AbjZQTQXjoMJyN3xR5Gsn8ICxdai Xu7t7cqPjWLp3OKpzmjm6RO2xVkHBb62aki57aZ5wmeGKtAtlfvA91vIt85RvaVvi7Xl OYwNEiYRnYIiTuqRKoKaiEP9DF8KFsL82AhsHk5gCqWJ2ht2id2779AWeDgC9cfC8Gdr LFAg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=YMeIfO7c; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id m20-v6sor7870356qvm.25.2018.08.01.08.17.34 for (Google Transport Security); Wed, 01 Aug 2018 08:17:34 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=YMeIfO7c; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=EOH4yuXU61UFUoCxssnGS0E9pmyAjCBzpOCJhmVNCYY=; b=YMeIfO7cHaOPiMpMbEL3NOKawxOjbeGFP0k9cxcW/u73CdC8UdEjGti+n/J1hepbbL zC9EPQ6M3PsLnBBXu7zrA5qGMcnCgHgagLN5jzI9+SmcImMJ961PzYjpSy45FkXX0JZw 0eAz+TM8bpe3OY27wnif6jAJ8/W4uBGXYf3fvtSHMoZ0RqTjQt589ELUAgAfzwQ2ojr+ jkjjPbmQoZ9q0yzFS9xHB+gBuD9Lvz9GjaGpD1GL9Bvs1M/hMOlWdjgmBnGYs5V2O6SN YNN1XzVzvzPZx98pl+pkHX8yqqelvVMDJ+ZoYPpNA5PyWTg8YW5QcvjCMws1CkX9fo8r xyPQ== X-Google-Smtp-Source: AAOMgpeUwxxVwE79rZ0AeguIBPrw6fa3hN35INPzAmkwgRZJ3nR0gQGHLrKgRnEqqtyC2D7jwYOOgA== X-Received: by 2002:a0c:f8ce:: with SMTP id h14-v6mr23582982qvo.163.1533136654208; Wed, 01 Aug 2018 08:17:34 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id k38-v6sm13787746qtc.45.2018.08.01.08.17.32 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:33 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 7/9] sched: introduce this_rq_lock_irq() Date: Wed, 1 Aug 2018 11:19:56 -0400 Message-Id: <20180801151958.32590-8-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP do_sched_yield() disables IRQs, looks up this_rq() and locks it. The next patch is adding another site with the same pattern, so provide a convenience function for it. Signed-off-by: Johannes Weiner --- kernel/sched/core.c | 4 +--- kernel/sched/sched.h | 12 ++++++++++++ 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 211890edf37e..9586a8141f16 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4960,9 +4960,7 @@ static void do_sched_yield(void) struct rq_flags rf; struct rq *rq; - local_irq_disable(); - rq = this_rq(); - rq_lock(rq, &rf); + rq = this_rq_lock_irq(&rf); schedstat_inc(rq->yld_count); current->sched_class->yield_task(rq); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index b8f038497240..bc798c7cb4d4 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1119,6 +1119,18 @@ rq_unlock(struct rq *rq, struct rq_flags *rf) raw_spin_unlock(&rq->lock); } +static inline struct rq * +this_rq_lock_irq(struct rq_flags *rf) + __acquires(rq->lock) +{ + struct rq *rq; + + local_irq_disable(); + rq = this_rq(); + rq_lock(rq, rf); + return rq; +} + #ifdef CONFIG_NUMA enum numa_topology_type { NUMA_DIRECT, From patchwork Wed Aug 1 15:19:57 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552471 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AC60F14E2 for ; Wed, 1 Aug 2018 15:17:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 96A612AC7E for ; Wed, 1 Aug 2018 15:17:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 863252B2BC; Wed, 1 Aug 2018 15:17:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 833702B5AF for ; Wed, 1 Aug 2018 15:17:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 14A666B0284; Wed, 1 Aug 2018 11:17:41 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 05EDC6B0286; Wed, 1 Aug 2018 11:17:40 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DA6446B0287; Wed, 1 Aug 2018 11:17:40 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qt0-f197.google.com (mail-qt0-f197.google.com [209.85.216.197]) by kanga.kvack.org (Postfix) with ESMTP id 9D2CB6B0284 for ; Wed, 1 Aug 2018 11:17:40 -0400 (EDT) Received: by mail-qt0-f197.google.com with SMTP id g7-v6so16092730qtp.19 for ; Wed, 01 Aug 2018 08:17:40 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=EBN3xTwc76TOo9IJxT2BSAFsu4RBtS+aXc8bxSb3SPw=; b=b4gOSDuzI9L3uX4jHOAmow9yaUgMFBkIHcEJOPNtLKjm/Qb7RLw1CGu6JpvG/mRqEJ 91XlO2IxAwZiVxD5GMK29OjeoSu2ky3O9c1RuJIyjCrqq4QIm+WDa43pSnSUXEbTpcyW zIqICdAz/78S1Pq2hcRpngtq+Vehsyy20mspIeatZcJzkK/15t1+iV/3YIV78dn0yerK Q9CKjSd6s4Q59vzxBwIfQFujleh7iuq7WR5SHraW+imj+jmjzzALeh4ubqt4VpVmFYix 9Wi0Rz/7axjRGQk5oLHHkHYpzsqPFwv+aOx0NiRHq+XmHRnVzqJCsV6//Nd6nNVtXpMS YUBQ== X-Gm-Message-State: AOUpUlGKywCK7UaC836KOPyDrmDrMT4K/N8GT7LalhXOzll/BZx57iNw zsLnkwlHAZRlPZ23d30d1E/7zwG3n70iErSHtwMEDhwLr6ck30iH7rjlCsGkxj+84eHpSuK5pVC FiI1er4/p4cSHLVYvHcnV4kxJiaVykJja0nIKvOpPgp9TgM6OvXvqCWLjpxli4KDCCytfXGOzST JGkIkc7/7EyMjQkxXHUcH54sQrQbyCZOhthJvarykeHndpBQWebXqw2JjeEsR+MjxuspuqgUQ6Q Cyo29niQtJT5ldyNsGDgPrsLak+oqykYQFJnLAC44vqiAXXRV8SxFvCcudqjDb8+/D2bTkvnoPQ yIEBqD7aogTJoaNuIakeq4oFJ6z/oiH06kdYpU1eB+muvhUzu3WitdvsnbwG37eRjnoPjSUP6Yr c X-Received: by 2002:ac8:7107:: with SMTP id z7-v6mr24313210qto.326.1533136660300; Wed, 01 Aug 2018 08:17:40 -0700 (PDT) X-Received: by 2002:ac8:7107:: with SMTP id z7-v6mr24313033qto.326.1533136657625; Wed, 01 Aug 2018 08:17:37 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136657; cv=none; d=google.com; s=arc-20160816; b=a/vS+u1pQ07p6u9t82h7DPGV/6NYvRORbap1j0ZJivpUkodXoeUF26lBaoah98ah4E 4+ZUKeFIujssB+Gxbq/mvLqD/6JjczjLSmYHPWeR3OhuXRIecb9CkP7rqytir8MB7Uod bofI72X9jCmO+0gyWIUXKwx0XDCA0FmDKllIWZfc33O7RMGc7hVxozwHFa5IK6XIjRIO pHJB1hDOD0IxRSRLI9eOkJx9aeOZMf4fQZFmr7WWdmv4A85HQ9bleyx3+sPCCUS7hzGg hm0Bml0u6XazZRLog/pYt+BwhXSHJ4mzx/OSUHOL4F1oMv7y2qCQqS3mVjH8dErVoZoJ o69g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=EBN3xTwc76TOo9IJxT2BSAFsu4RBtS+aXc8bxSb3SPw=; b=gvM7gY0jaFCf4+Enj5tHgZdalRq6UlzbznUdvcA84/IIk2YMNK0a5BYYjxcJJTb5k/ jnxwLe8yq0PkgcQZpk3roN/8vgMTrhird+0KnDaQGxYglx40/pYSOWkfl1X6Fa0Wr4Hb PgxCY3SHuHn73iPCjH8krIFRsF5xeim95m7GCnOvmZpsj8GyAk4S9FpJKlzB/LydMG3f aoRAdqXoFGjsSMTbLNMhwSpdMonW/EI8wMQx1d1R905iYsj/Do3b0Ft5cuYR70jf9ekr wzcSZQ4XJ9UvPh55GOQY5q0A3zcOyuWhIjjsqbGLyZ0mOkAfVhBUuqfJ8ckVYAukXhNP QMJQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=lUs7YYpa; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id e9-v6sor3079374qkm.8.2018.08.01.08.17.37 for (Google Transport Security); Wed, 01 Aug 2018 08:17:37 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=lUs7YYpa; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=EBN3xTwc76TOo9IJxT2BSAFsu4RBtS+aXc8bxSb3SPw=; b=lUs7YYpabsyrq3PyG2vxsWFJo67/UQv+cRHXjr5URfCcYGytfGrWrOlvsikVfTiqNq elmgZ54nfrGUBmc9CYaSuuPuMXL55xu7ALlojN2hPE4M7njunCAh2Uzifv5PGwdWF+9l +7jnVP88nhtL7jj+ZC+Q01FXtupyQQkeCb0qJuFBFmBORdBXa9saLBNKkHaQrNgbwi5J 2J+pVlItwc05U4ZDIFEdqjHHdlhGY57YPq3t94w46nTHK3+LDUDGrID+FM09aLyanvkg EjBnftDHNK0qmY8gYeoKXs50MrlXJNcV3ANX7JOJWoXYEFavorUhsxV694eO+VIthXxH fjYw== X-Google-Smtp-Source: AAOMgpfOiHWQrBsb9yMvYzIdgcka93gan0mQwZbcKzo1ar9ppReCod7FTFVTC3v/2jUuJ0gt762Fag== X-Received: by 2002:a37:1328:: with SMTP id d40-v6mr23825229qkh.198.1533136656243; Wed, 01 Aug 2018 08:17:36 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id q15-v6sm14249559qte.55.2018.08.01.08.17.34 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:35 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 8/9] psi: pressure stall information for CPU, memory, and IO Date: Wed, 1 Aug 2018 11:19:57 -0400 Message-Id: <20180801151958.32590-9-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP When systems are overcommitted and resources become contended, it's hard to tell exactly the impact this has on workload productivity, or how close the system is to lockups and OOM kills. In particular, when machines work multiple jobs concurrently, the impact of overcommit in terms of latency and throughput on the individual job can be enormous. In order to maximize hardware utilization without sacrificing individual job health or risk complete machine lockups, this patch implements a way to quantify resource pressure in the system. A kernel built with CONFIG_PSI=y creates files in /proc/pressure/ that expose the percentage of time the system is stalled on CPU, memory, or IO, respectively. Stall states are aggregate versions of the per-task delay accounting delays: cpu: some tasks are runnable but not executing on a CPU memory: tasks are reclaiming, or waiting for swapin or thrashing cache io: tasks are waiting for io completions These percentages of walltime can be thought of as pressure percentages, and they give a general sense of system health and productivity loss incurred by resource overcommit. They can also indicate when the system is approaching lockup scenarios and OOMs. To do this, psi keeps track of the task states associated with each CPU and samples the time they spend in stall states. Every 2 seconds, the samples are averaged across CPUs - weighted by the CPUs' non-idle time to eliminate artifacts from unused CPUs - and translated into percentages of walltime. A running average of those percentages is maintained over 10s, 1m, and 5m periods (similar to the loadaverage). v2: - stable clock tick, as per Peter - data structure layout optimization, as per Peter - fix u64 divisions on 32 bit, as per Peter - outermost psi_disabled checks, as per Peter - coding style fixes, as per Peter - just-in-time stats aggregation, as per Suren - fix task state corruption with CONFIG_PREEMPT, as per Suren - CONFIG_PSI=n build error - avoid writing p->sched_psi_wake_requeue unnecessarily - documentation & comment updates v3: - pack scheduler hotpath data into one cacheline, as per Peter and Linus - drop unnecessary SCHED_INFO dependency, as per Peter - lockless live-state aggregation, as per Peter - do_div -> div64_ul and some other cleanups, as per Peter - realtime sampling period and slipped sample handling, as per Tejun Signed-off-by: Johannes Weiner --- Documentation/accounting/psi.txt | 64 +++ include/linux/psi.h | 27 ++ include/linux/psi_types.h | 87 +++++ include/linux/sched.h | 10 + init/Kconfig | 15 + kernel/fork.c | 4 + kernel/sched/Makefile | 1 + kernel/sched/core.c | 11 +- kernel/sched/psi.c | 643 +++++++++++++++++++++++++++++++ kernel/sched/sched.h | 2 + kernel/sched/stats.h | 80 ++++ mm/compaction.c | 5 + mm/filemap.c | 15 +- mm/page_alloc.c | 10 + mm/vmscan.c | 13 + 15 files changed, 981 insertions(+), 6 deletions(-) create mode 100644 Documentation/accounting/psi.txt create mode 100644 include/linux/psi.h create mode 100644 include/linux/psi_types.h create mode 100644 kernel/sched/psi.c diff --git a/Documentation/accounting/psi.txt b/Documentation/accounting/psi.txt new file mode 100644 index 000000000000..51e7ef14142e --- /dev/null +++ b/Documentation/accounting/psi.txt @@ -0,0 +1,64 @@ +================================ +PSI - Pressure Stall Information +================================ + +:Date: April, 2018 +:Author: Johannes Weiner + +When CPU, memory or IO devices are contended, workloads experience +latency spikes, throughput losses, and run the risk of OOM kills. + +Without an accurate measure of such contention, users are forced to +either play it safe and under-utilize their hardware resources, or +roll the dice and frequently suffer the disruptions resulting from +excessive overcommit. + +The psi feature identifies and quantifies the disruptions caused by +such resource crunches and the time impact it has on complex workloads +or even entire systems. + +Having an accurate measure of productivity losses caused by resource +scarcity aids users in sizing workloads to hardware--or provisioning +hardware according to workload demand. + +As psi aggregates this information in realtime, systems can be managed +dynamically using techniques such as load shedding, migrating jobs to +other systems or data centers, or strategically pausing or killing low +priority or restartable batch jobs. + +This allows maximizing hardware utilization without sacrificing +workload health or risking major disruptions such as OOM kills. + +Pressure interface +================== + +Pressure information for each resource is exported through the +respective file in /proc/pressure/ -- cpu, memory, and io. + +In both cases, the format for CPU is as such: + +some avg10=0.00 avg60=0.00 avg300=0.00 total=0 + +and for memory and IO: + +some avg10=0.00 avg60=0.00 avg300=0.00 total=0 +full avg10=0.00 avg60=0.00 avg300=0.00 total=0 + +The "some" line indicates the share of time in which at least some +tasks are stalled on a given resource. + +The "full" line indicates the share of time in which all non-idle +tasks are stalled on a given resource simultaneously. In this state +actual CPU cycles are going to waste, and a workload that spends +extended time in this state is considered to be thrashing. This has +severe impact on performance, and it's useful to distinguish this +situation from a state where some tasks are stalled but the CPU is +still doing productive work. As such, time spent in this subset of the +stall state is tracked separately and exported in the "full" averages. + +The ratios are tracked as recent trends over ten, sixty, and three +hundred second windows, which gives insight into short term events as +well as medium and long term trends. The total absolute stall time is +tracked and exported as well, to allow detection of latency spikes +which wouldn't necessarily make a dent in the time averages, or to +average trends over custom time frames. diff --git a/include/linux/psi.h b/include/linux/psi.h new file mode 100644 index 000000000000..371af1479699 --- /dev/null +++ b/include/linux/psi.h @@ -0,0 +1,27 @@ +#ifndef _LINUX_PSI_H +#define _LINUX_PSI_H + +#include +#include + +#ifdef CONFIG_PSI + +extern bool psi_disabled; + +void psi_init(void); + +void psi_task_change(struct task_struct *task, u64 now, int clear, int set); + +void psi_memstall_enter(unsigned long *flags); +void psi_memstall_leave(unsigned long *flags); + +#else /* CONFIG_PSI */ + +static inline void psi_init(void) {} + +static inline void psi_memstall_enter(unsigned long *flags) {} +static inline void psi_memstall_leave(unsigned long *flags) {} + +#endif /* CONFIG_PSI */ + +#endif /* _LINUX_PSI_H */ diff --git a/include/linux/psi_types.h b/include/linux/psi_types.h new file mode 100644 index 000000000000..b6ff46362eb3 --- /dev/null +++ b/include/linux/psi_types.h @@ -0,0 +1,87 @@ +#ifndef _LINUX_PSI_TYPES_H +#define _LINUX_PSI_TYPES_H + +#include + +#ifdef CONFIG_PSI + +/* Tracked task states */ +enum psi_task_count { + NR_IOWAIT, + NR_MEMSTALL, + NR_RUNNING, + NR_PSI_TASK_COUNTS, +}; + +/* Task state bitmasks */ +#define TSK_IOWAIT (1 << NR_IOWAIT) +#define TSK_MEMSTALL (1 << NR_MEMSTALL) +#define TSK_RUNNING (1 << NR_RUNNING) + +/* Resources that workloads could be stalled on */ +enum psi_res { + PSI_IO, + PSI_MEM, + PSI_CPU, + NR_PSI_RESOURCES, +}; + +/* + * Pressure states for each resource: + * + * SOME: Stalled tasks & working tasks + * FULL: Stalled tasks & no working tasks + */ +enum psi_states { + PSI_IO_SOME, + PSI_IO_FULL, + PSI_MEM_SOME, + PSI_MEM_FULL, + PSI_CPU_SOME, + PSI_NONIDLE, + NR_PSI_STATES, +}; + +struct psi_group_cpu { + /* 1st cacheline updated by the scheduler */ + + /* States of the tasks belonging to this group */ + unsigned int tasks[NR_PSI_TASK_COUNTS] ____cacheline_aligned_in_smp; + + /* Period time sampling buckets for each state of interest (ns) */ + u32 times[NR_PSI_STATES]; + + /* Time of last task change in this group (rq_clock) */ + u64 state_start; + + /* 2nd cacheline updated by the aggregator */ + + /* Delta detection against the sampling buckets */ + u32 times_prev[NR_PSI_STATES] ____cacheline_aligned_in_smp; +}; + +struct psi_group { + /* Protects data updated during an aggregation */ + struct mutex stat_lock; + + /* Per-cpu task state & time tracking */ + struct psi_group_cpu __percpu *pcpu; + + /* Periodic aggregation state */ + u64 total_prev[NR_PSI_STATES - 1]; + u64 last_update; + u64 next_update; + struct delayed_work clock_work; + + /* Total stall times and sampled pressure averages */ + u64 total[NR_PSI_STATES - 1]; + unsigned long avg[NR_PSI_STATES - 1][3]; +}; + +#else /* CONFIG_PSI */ + +struct psi_group { }; + +#endif /* CONFIG_PSI */ + +#endif /* _LINUX_PSI_TYPES_H */ diff --git a/include/linux/sched.h b/include/linux/sched.h index ca3f3eae8980..d5e4ee234114 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -709,6 +710,10 @@ struct task_struct { unsigned sched_contributes_to_load:1; unsigned sched_migrated:1; unsigned sched_remote_wakeup:1; +#ifdef CONFIG_PSI + unsigned sched_psi_wake_requeue:1; +#endif + /* Force alignment to the next boundary: */ unsigned :0; @@ -956,6 +961,10 @@ struct task_struct { siginfo_t *last_siginfo; struct task_io_accounting ioac; +#ifdef CONFIG_PSI + /* Pressure stall state */ + unsigned int psi_flags; +#endif #ifdef CONFIG_TASK_XACCT /* Accumulated RSS usage: */ u64 acct_rss_mem1; @@ -1385,6 +1394,7 @@ extern struct pid *cad_pid; #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ +#define PF_MEMSTALL 0x01000000 /* Stalled due to lack of memory */ #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ diff --git a/init/Kconfig b/init/Kconfig index 18b151f0ddc1..ad61ddb5d68e 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -457,6 +457,21 @@ config TASK_IO_ACCOUNTING Say N if unsure. +config PSI + bool "Pressure stall information tracking" + help + Collect metrics that indicate how overcommitted the CPU, memory, + and IO capacity are in the system. + + If you say Y here, the kernel will create /proc/pressure/ with the + pressure statistics files cpu, memory, and io. These will indicate + the share of walltime in which some or all tasks in the system are + delayed due to contention of the respective resource. + + For more details see Documentation/accounting/psi.txt. + + Say N if unsure. + endmenu # "CPU/Task time and stats accounting" config CPU_ISOLATION diff --git a/kernel/fork.c b/kernel/fork.c index a5d21c42acfc..067aa5c28526 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1704,6 +1704,10 @@ static __latent_entropy struct task_struct *copy_process( p->default_timer_slack_ns = current->timer_slack_ns; +#ifdef CONFIG_PSI + p->psi_flags = 0; +#endif + task_io_accounting_init(&p->ioac); acct_clear_integrals(p); diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile index d9a02b318108..b29bc18f2704 100644 --- a/kernel/sched/Makefile +++ b/kernel/sched/Makefile @@ -29,3 +29,4 @@ obj-$(CONFIG_CPU_FREQ) += cpufreq.o obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o obj-$(CONFIG_MEMBARRIER) += membarrier.o obj-$(CONFIG_CPU_ISOLATION) += isolation.o +obj-$(CONFIG_PSI) += psi.o diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 9586a8141f16..e53137df405b 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -743,8 +743,10 @@ static inline void enqueue_task(struct rq *rq, struct task_struct *p, int flags) if (!(flags & ENQUEUE_NOCLOCK)) update_rq_clock(rq); - if (!(flags & ENQUEUE_RESTORE)) + if (!(flags & ENQUEUE_RESTORE)) { sched_info_queued(rq, p); + psi_enqueue(rq, p, flags & ENQUEUE_WAKEUP); + } p->sched_class->enqueue_task(rq, p, flags); } @@ -754,8 +756,10 @@ static inline void dequeue_task(struct rq *rq, struct task_struct *p, int flags) if (!(flags & DEQUEUE_NOCLOCK)) update_rq_clock(rq); - if (!(flags & DEQUEUE_SAVE)) + if (!(flags & DEQUEUE_SAVE)) { sched_info_dequeued(rq, p); + psi_dequeue(rq, p, flags & DEQUEUE_SLEEP); + } p->sched_class->dequeue_task(rq, p, flags); } @@ -2058,6 +2062,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) cpu = select_task_rq(p, p->wake_cpu, SD_BALANCE_WAKE, wake_flags); if (task_cpu(p) != cpu) { wake_flags |= WF_MIGRATED; + psi_ttwu_dequeue(p); set_task_cpu(p, cpu); } @@ -6124,6 +6129,8 @@ void __init sched_init(void) init_schedstats(); + psi_init(); + scheduler_running = 1; } diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c new file mode 100644 index 000000000000..57ec86592b5a --- /dev/null +++ b/kernel/sched/psi.c @@ -0,0 +1,643 @@ +/* + * Pressure stall information for CPU, memory and IO + * + * Copyright (c) 2018 Facebook, Inc. + * Author: Johannes Weiner + * + * When CPU, memory and IO are contended, tasks experience delays that + * reduce throughput and introduce latencies into the workload. Memory + * and IO contention, in addition, can cause a full loss of forward + * progress in which the CPU goes idle. + * + * This code aggregates individual task delays into resource pressure + * metrics that indicate problems with both workload health and + * resource utilization. + * + * Model + * + * The time in which a task can execute on a CPU is our baseline for + * productivity. Pressure expresses the amount of time in which this + * potential cannot be realized due to resource contention. + * + * This concept of productivity has two components: the workload and + * the CPU. To measure the impact of pressure on both, we define two + * contention states for a resource: SOME and FULL. + * + * In the SOME state of a given resource, one or more tasks are + * delayed on that resource. This affects the workload's ability to + * perform work, but the CPU may still be executing other tasks. + * + * In the FULL state of a given resource, all non-idle tasks are + * delayed on that resource such that nobody is advancing and the CPU + * goes idle. This leaves both workload and CPU unproductive. + * + * (Naturally, the FULL state doesn't exist for the CPU resource.) + * + * SOME = nr_delayed_tasks != 0 + * FULL = nr_delayed_tasks != 0 && nr_running_tasks == 0 + * + * The percentage of wallclock time spent in those compound stall + * states gives pressure numbers between 0 and 100 for each resource, + * where the SOME percentage indicates workload slowdowns and the FULL + * percentage indicates reduced CPU utilization: + * + * %SOME = time(SOME) / period + * %FULL = time(FULL) / period + * + * Multiple CPUs + * + * The more tasks and available CPUs there are, the more work can be + * performed concurrently. This means that the potential that can go + * unrealized due to resource contention *also* scales with non-idle + * tasks and CPUs. + * + * Consider a scenario where 257 number crunching tasks are trying to + * run concurrently on 256 CPUs. If we simply aggregated the task + * states, we would have to conclude a CPU SOME pressure number of + * 100%, since *somebody* is waiting on a runqueue at all + * times. However, that is clearly not the amount of contention the + * workload is experiencing: only one out of 256 possible exceution + * threads will be contended at any given time, or about 0.4%. + * + * Conversely, consider a scenario of 4 tasks and 4 CPUs where at any + * given time *one* of the tasks is delayed due to a lack of memory. + * Again, looking purely at the task state would yield a memory FULL + * pressure number of 0%, since *somebody* is always making forward + * progress. But again this wouldn't capture the amount of execution + * potential lost, which is 1 out of 4 CPUs, or 25%. + * + * To calculate wasted potential (pressure) with multiple processors, + * we have to base our calculation on the number of non-idle tasks in + * conjunction with the number of available CPUs, which is the number + * of potential execution threads. SOME becomes then the proportion of + * delayed tasks to possibe threads, and FULL is the share of possible + * threads that are unproductive due to delays: + * + * threads = min(nr_nonidle_tasks, nr_cpus) + * SOME = min(nr_delayed_tasks / threads, 1) + * FULL = (threads - min(nr_running_tasks, threads)) / threads + * + * For the 257 number crunchers on 256 CPUs, this yields: + * + * threads = min(257, 256) + * SOME = min(1 / 256, 1) = 0.4% + * FULL = (256 - min(257, 256)) / 256 = 0% + * + * For the 1 out of 4 memory-delayed tasks, this yields: + * + * threads = min(4, 4) + * SOME = min(1 / 4, 1) = 25% + * FULL = (4 - min(3, 4)) / 4 = 25% + * + * [ Substitute nr_cpus with 1, and you can see that it's a natural + * extension of the single-CPU model. ] + * + * Implementation + * + * To assess the precise time spent in each such state, we would have + * to freeze the system on task changes and start/stop the state + * clocks accordingly. Obviously that doesn't scale in practice. + * + * Because the scheduler aims to distribute the compute load evenly + * among the available CPUs, we can track task state locally to each + * CPU and, at much lower frequency, extrapolate the global state for + * the cumulative stall times and the running averages. + * + * For each runqueue, we track: + * + * tSOME[cpu] = time(nr_delayed_tasks[cpu] != 0) + * tFULL[cpu] = time(nr_delayed_tasks[cpu] && !nr_running_tasks[cpu]) + * tNONIDLE[cpu] = time(nr_nonidle_tasks[cpu] != 0) + * + * and then periodically aggregate: + * + * tNONIDLE = sum(tNONIDLE[i]) + * + * tSOME = sum(tSOME[i] * tNONIDLE[i]) / tNONIDLE + * tFULL = sum(tFULL[i] * tNONIDLE[i]) / tNONIDLE + * + * %SOME = tSOME / period + * %FULL = tFULL / period + * + * This gives us an approximation of pressure that is practical + * cost-wise, yet way more sensitive and accurate than periodic + * sampling of the aggregate task states would be. + */ + +#include +#include +#include +#include +#include +#include +#include +#include "sched.h" + +static int psi_bug __read_mostly; + +bool psi_disabled __read_mostly; +core_param(psi_disabled, psi_disabled, bool, 0644); + +/* Running averages - we need to be higher-res than loadavg */ +#define PSI_FREQ (2*HZ+1) /* 2 sec intervals */ +#define EXP_10s 1677 /* 1/exp(2s/10s) as fixed-point */ +#define EXP_60s 1981 /* 1/exp(2s/60s) */ +#define EXP_300s 2034 /* 1/exp(2s/300s) */ + +/* Sampling frequency in nanoseconds */ +static u64 psi_period __read_mostly; + +/* System-level pressure and stall tracking */ +static DEFINE_PER_CPU(struct psi_group_cpu, system_group_pcpu); +static struct psi_group psi_system = { + .pcpu = &system_group_pcpu, +}; + +static void psi_clock(struct work_struct *work); + +static void psi_group_init(struct psi_group *group) +{ + group->next_update = sched_clock() + psi_period; + INIT_DELAYED_WORK(&group->clock_work, psi_clock); + mutex_init(&group->stat_lock); +} + +void __init psi_init(void) +{ + if (psi_disabled) + return; + + psi_period = jiffies_to_nsecs(PSI_FREQ); + psi_group_init(&psi_system); +} + +static void calc_avgs(unsigned long avg[3], int missed_periods, + u64 time, u64 period) +{ + unsigned long pct; + + /* Fill in zeroes for periods of no activity */ + if (missed_periods) { + avg[0] = calc_load_n(avg[0], EXP_10s, 0, missed_periods); + avg[1] = calc_load_n(avg[1], EXP_60s, 0, missed_periods); + avg[2] = calc_load_n(avg[2], EXP_300s, 0, missed_periods); + } + + /* Sample the most recent active period */ + pct = div_u64(time * 100, period); + pct *= FIXED_1; + avg[0] = calc_load(avg[0], EXP_10s, pct); + avg[1] = calc_load(avg[1], EXP_60s, pct); + avg[2] = calc_load(avg[2], EXP_300s, pct); +} + +static bool test_state(unsigned int *tasks, int cpu, enum psi_states state) +{ + switch (state) { + case PSI_IO_SOME: + return tasks[NR_IOWAIT]; + case PSI_IO_FULL: + return tasks[NR_IOWAIT] && !tasks[NR_RUNNING]; + case PSI_MEM_SOME: + return tasks[NR_MEMSTALL]; + case PSI_MEM_FULL: + /* + * Since we care about lost potential, things are + * fully blocked on memory when there are no other + * working tasks, but also when the CPU is actively + * being used by a reclaimer and nothing productive + * could run even if it were runnable. + */ + return tasks[NR_MEMSTALL] && + (!tasks[NR_RUNNING] || + cpu_curr(cpu)->flags & PF_MEMSTALL); + case PSI_CPU_SOME: + return tasks[NR_RUNNING] > 1; + case PSI_NONIDLE: + return tasks[NR_IOWAIT] || tasks[NR_MEMSTALL] || + tasks[NR_RUNNING]; + default: + return false; + } +} + +static bool psi_update_stats(struct psi_group *group) +{ + u64 deltas[NR_PSI_STATES - 1] = { 0, }; + unsigned long missed_periods = 0; + unsigned long nonidle_total = 0; + u64 now, expires, period; + int cpu; + int s; + + mutex_lock(&group->stat_lock); + + /* + * Collect the per-cpu time buckets and average them into a + * single time sample that is normalized to wallclock time. + * + * For averaging, each CPU is weighted by its non-idle time in + * the sampling period. This eliminates artifacts from uneven + * loading, or even entirely idle CPUs. + * + * We don't need to synchronize against CPU hotplugging. If we + * see a CPU that's online and has samples, we incorporate it. + */ + for_each_online_cpu(cpu) { + struct psi_group_cpu *groupc = per_cpu_ptr(group->pcpu, cpu); + u32 uninitialized_var(nonidle); + + BUILD_BUG_ON(PSI_NONIDLE != NR_PSI_STATES - 1); + + for (s = PSI_NONIDLE; s >= 0; s--) { + u32 time, delta; + + time = READ_ONCE(groupc->times[s]); + /* + * In addition to already concluded states, we + * also incorporate currently active states on + * the CPU, since states may last for many + * sampling periods. + * + * This way we keep our delta sampling buckets + * small (u32) and our reported pressure close + * to what's actually happening. + */ + if (test_state(groupc->tasks, cpu, s)) { + /* + * We can race with a state change and + * need to make sure the state_start + * update is ordered against the + * updates to the live state and the + * time buckets (groupc->times). + * + * 1. If we observe task state that + * needs to be recorded, make sure we + * see state_start from when that + * state went into effect or we'll + * count time from the previous state. + * + * 2. If the time delta has already + * been added to the bucket, make sure + * we don't see it in state_start or + * we'll count it twice. + * + * If the time delta is out of + * state_start but not in the time + * bucket yet, we'll miss it entirely + * and handle it in the next period. + */ + smp_rmb(); + time += cpu_clock(cpu) - groupc->state_start; + } + delta = time - groupc->times_prev[s]; + groupc->times_prev[s] = time; + + if (s == PSI_NONIDLE) { + nonidle = nsecs_to_jiffies(delta); + nonidle_total += nonidle; + } else { + deltas[s] += (u64)delta * nonidle; + } + } + } + + /* + * Integrate the sample into the running statistics that are + * reported to userspace: the cumulative stall times and the + * decaying averages. + * + * Pressure percentages are sampled at PSI_FREQ. We might be + * called more often when the user polls more frequently than + * that; we might be called less often when there is no task + * activity, thus no data, and clock ticks are sporadic. The + * below handles both. + */ + + /* total= */ + for (s = 0; s < NR_PSI_STATES - 1; s++) + group->total[s] += div_u64(deltas[s], max(nonidle_total, 1UL)); + + /* avgX= */ + now = sched_clock(); + expires = group->next_update; + if (now < expires) + goto out; + if (now - expires > psi_period) + missed_periods = div_u64(now - expires, psi_period); + + /* + * The periodic clock tick can get delayed for various + * reasons, especially on loaded systems. To avoid clock + * drift, we schedule the clock in fixed psi_period intervals. + * But the deltas we sample out of the per-cpu buckets above + * are based on the actual time elapsing between clock ticks. + */ + group->next_update = expires + ((1 + missed_periods) * psi_period); + period = now - (group->last_update + (missed_periods * psi_period)); + group->last_update = now; + + for (s = 0; s < NR_PSI_STATES - 1; s++) { + u32 sample; + + sample = group->total[s] - group->total_prev[s]; + /* + * Due to the lockless sampling of the time buckets, + * recorded time deltas can slip into the next period, + * which under full pressure can result in samples in + * excess of the period length. + * + * We don't want to report non-sensical pressures in + * excess of 100%, nor do we want to drop such events + * on the floor. Instead we punt any overage into the + * future until pressure subsides. By doing this we + * don't underreport the occurring pressure curve, we + * just report it delayed by one period length. + * + * The error isn't cumulative. As soon as another + * delta slips from a period P to P+1, by definition + * it frees up its time T in P. + */ + if (sample > period) + sample = period; + group->total_prev[s] += sample; + calc_avgs(group->avg[s], missed_periods, sample, period); + } +out: + mutex_unlock(&group->stat_lock); + return nonidle_total; +} + +static void psi_clock(struct work_struct *work) +{ + struct delayed_work *dwork; + struct psi_group *group; + bool nonidle; + + dwork = to_delayed_work(work); + group = container_of(dwork, struct psi_group, clock_work); + + /* + * If there is task activity, periodically fold the per-cpu + * times and feed samples into the running averages. If things + * are idle and there is no data to process, stop the clock. + * Once restarted, we'll catch up the running averages in one + * go - see calc_avgs() and missed_periods. + */ + + nonidle = psi_update_stats(group); + + if (nonidle) { + unsigned long delay = 0; + u64 now; + + now = sched_clock(); + if (group->next_update > now) + delay = nsecs_to_jiffies(group->next_update - now) + 1; + schedule_delayed_work(dwork, delay); + } +} + +static void psi_group_change(struct psi_group *group, int cpu, u64 now, + unsigned int clear, unsigned int set) +{ + struct psi_group_cpu *groupc; + unsigned int t, m; + u32 delta; + + groupc = per_cpu_ptr(group->pcpu, cpu); + + /* + * First we assess the aggregate resource states these CPU's + * tasks have been in since the last change, and account any + * SOME and FULL time that may have resulted in. + * + * Then we update the task counts according to the state + * change requested through the @clear and @set bits. + */ + + delta = now - groupc->state_start; + groupc->state_start = now; + + /* + * Update state_start before recording time in the sampling + * buckets and changing task counts, to prevent a racing + * aggregation from counting the delta twice or attributing it + * to an old state. + */ + smp_wmb(); + + if (test_state(groupc->tasks, cpu, PSI_IO_SOME)) { + groupc->times[PSI_IO_SOME] += delta; + if (test_state(groupc->tasks, cpu, PSI_IO_FULL)) + groupc->times[PSI_IO_FULL] += delta; + } + if (test_state(groupc->tasks, cpu, PSI_MEM_SOME)) { + groupc->times[PSI_MEM_SOME] += delta; + if (test_state(groupc->tasks, cpu, PSI_MEM_FULL)) + groupc->times[PSI_MEM_FULL] += delta; + } + if (test_state(groupc->tasks, cpu, PSI_CPU_SOME)) + groupc->times[PSI_CPU_SOME] += delta; + if (test_state(groupc->tasks, cpu, PSI_NONIDLE)) + groupc->times[PSI_NONIDLE] += delta; + + for (t = 0, m = clear; m; m &= ~(1 << t), t++) { + if (!(m & (1 << t))) + continue; + if (groupc->tasks[t] == 0 && !psi_bug) { + printk_deferred(KERN_ERR "psi: task underflow! cpu=%d t=%d tasks=[%u %u %u] clear=%x set=%x\n", + cpu, t, groupc->tasks[0], + groupc->tasks[1], groupc->tasks[2], + clear, set); + psi_bug = 1; + } + groupc->tasks[t]--; + } + for (t = 0; set; set &= ~(1 << t), t++) + if (set & (1 << t)) + groupc->tasks[t]++; + + if (!delayed_work_pending(&group->clock_work)) + schedule_delayed_work(&group->clock_work, PSI_FREQ); +} + +void psi_task_change(struct task_struct *task, u64 now, int clear, int set) +{ + int cpu = task_cpu(task); + + if (psi_disabled) + return; + + if (!task->pid) + return; + + if (((task->psi_flags & set) || + (task->psi_flags & clear) != clear) && + !psi_bug) { + printk_deferred(KERN_ERR "psi: inconsistent task state! task=%d:%s cpu=%d psi_flags=%x clear=%x set=%x\n", + task->pid, task->comm, cpu, + task->psi_flags, clear, set); + psi_bug = 1; + } + + task->psi_flags &= ~clear; + task->psi_flags |= set; + + psi_group_change(&psi_system, cpu, now, clear, set); +} + +/** + * psi_memstall_enter - mark the beginning of a memory stall section + * @flags: flags to handle nested sections + * + * Marks the calling task as being stalled due to a lack of memory, + * such as waiting for a refault or performing reclaim. + */ +void psi_memstall_enter(unsigned long *flags) +{ + struct rq_flags rf; + struct rq *rq; + + if (psi_disabled) + return; + + *flags = current->flags & PF_MEMSTALL; + if (*flags) + return; + /* + * PF_MEMSTALL setting & accounting needs to be atomic wrt + * changes to the task's scheduling state, otherwise we can + * race with CPU migration. + */ + rq = this_rq_lock_irq(&rf); + + update_rq_clock(rq); + + current->flags |= PF_MEMSTALL; + psi_task_change(current, rq_clock(rq), 0, TSK_MEMSTALL); + + rq_unlock_irq(rq, &rf); +} + +/** + * psi_memstall_leave - mark the end of an memory stall section + * @flags: flags to handle nested memdelay sections + * + * Marks the calling task as no longer stalled due to lack of memory. + */ +void psi_memstall_leave(unsigned long *flags) +{ + struct rq_flags rf; + struct rq *rq; + + if (psi_disabled) + return; + + if (*flags) + return; + /* + * PF_MEMSTALL clearing & accounting needs to be atomic wrt + * changes to the task's scheduling state, otherwise we could + * race with CPU migration. + */ + rq = this_rq_lock_irq(&rf); + + update_rq_clock(rq); + + current->flags &= ~PF_MEMSTALL; + psi_task_change(current, rq_clock(rq), TSK_MEMSTALL, 0); + + rq_unlock_irq(rq, &rf); +} + +static int psi_show(struct seq_file *m, struct psi_group *group, + enum psi_res res) +{ + int full; + + if (psi_disabled) + return -EOPNOTSUPP; + + psi_update_stats(group); + + for (full = 0; full < 2 - (res == PSI_CPU); full++) { + unsigned long avg[3]; + u64 total; + int w; + + for (w = 0; w < 3; w++) + avg[w] = group->avg[res * 2 + full][w]; + total = div_u64(group->total[res * 2 + full], NSEC_PER_USEC); + + seq_printf(m, "%s avg10=%lu.%02lu avg60=%lu.%02lu avg300=%lu.%02lu total=%llu\n", + full ? "full" : "some", + LOAD_INT(avg[0]), LOAD_FRAC(avg[0]), + LOAD_INT(avg[1]), LOAD_FRAC(avg[1]), + LOAD_INT(avg[2]), LOAD_FRAC(avg[2]), + total); + } + + return 0; +} + +static int psi_io_show(struct seq_file *m, void *v) +{ + return psi_show(m, &psi_system, PSI_IO); +} + +static int psi_memory_show(struct seq_file *m, void *v) +{ + return psi_show(m, &psi_system, PSI_MEM); +} + +static int psi_cpu_show(struct seq_file *m, void *v) +{ + return psi_show(m, &psi_system, PSI_CPU); +} + +static int psi_io_open(struct inode *inode, struct file *file) +{ + return single_open(file, psi_io_show, NULL); +} + +static int psi_memory_open(struct inode *inode, struct file *file) +{ + return single_open(file, psi_memory_show, NULL); +} + +static int psi_cpu_open(struct inode *inode, struct file *file) +{ + return single_open(file, psi_cpu_show, NULL); +} + +static const struct file_operations psi_io_fops = { + .open = psi_io_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations psi_memory_fops = { + .open = psi_memory_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations psi_cpu_fops = { + .open = psi_cpu_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init psi_proc_init(void) +{ + proc_mkdir("pressure", NULL); + proc_create("pressure/io", 0, NULL, &psi_io_fops); + proc_create("pressure/memory", 0, NULL, &psi_memory_fops); + proc_create("pressure/cpu", 0, NULL, &psi_cpu_fops); + return 0; +} +module_init(psi_proc_init); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index bc798c7cb4d4..e798491ff329 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -54,6 +54,7 @@ #include #include #include +#include #include #include #include @@ -320,6 +321,7 @@ extern bool dl_cpu_busy(unsigned int cpu); #ifdef CONFIG_CGROUP_SCHED #include +#include struct cfs_rq; struct rt_rq; diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h index 8aea199a39b4..f3e0267eb47d 100644 --- a/kernel/sched/stats.h +++ b/kernel/sched/stats.h @@ -55,6 +55,86 @@ static inline void rq_sched_info_depart (struct rq *rq, unsigned long long delt # define schedstat_val_or_zero(var) 0 #endif /* CONFIG_SCHEDSTATS */ +#ifdef CONFIG_PSI +/* + * PSI tracks state that persists across sleeps, such as iowaits and + * memory stalls. As a result, it has to distinguish between sleeps, + * where a task's runnable state changes, and requeues, where a task + * and its state are being moved between CPUs and runqueues. + */ +static inline void psi_enqueue(struct rq *rq, struct task_struct *p, + bool wakeup) +{ + int clear = 0, set = TSK_RUNNING; + + if (psi_disabled) + return; + + if (!wakeup || p->sched_psi_wake_requeue) { + if (p->flags & PF_MEMSTALL) + set |= TSK_MEMSTALL; + if (p->sched_psi_wake_requeue) + p->sched_psi_wake_requeue = 0; + } else { + if (p->in_iowait) + clear |= TSK_IOWAIT; + } + + psi_task_change(p, rq_clock(rq), clear, set); +} + +static inline void psi_dequeue(struct rq *rq, struct task_struct *p, bool sleep) +{ + int clear = TSK_RUNNING, set = 0; + + if (psi_disabled) + return; + + if (!sleep) { + if (p->flags & PF_MEMSTALL) + clear |= TSK_MEMSTALL; + } else { + if (p->in_iowait) + set |= TSK_IOWAIT; + } + + psi_task_change(p, rq_clock(rq), clear, set); +} + +static inline void psi_ttwu_dequeue(struct task_struct *p) +{ + if (psi_disabled) + return; + /* + * Is the task being migrated during a wakeup? Make sure to + * deregister its sleep-persistent psi states from the old + * queue, and let psi_enqueue() know it has to requeue. + */ + if (unlikely(p->in_iowait || (p->flags & PF_MEMSTALL))) { + struct rq_flags rf; + struct rq *rq; + int clear = 0; + + if (p->in_iowait) + clear |= TSK_IOWAIT; + if (p->flags & PF_MEMSTALL) + clear |= TSK_MEMSTALL; + + rq = __task_rq_lock(p, &rf); + update_rq_clock(rq); + psi_task_change(p, rq_clock(rq), clear, 0); + p->sched_psi_wake_requeue = 1; + __task_rq_unlock(rq, &rf); + } +} +#else /* CONFIG_PSI */ +static inline void psi_enqueue(struct rq *rq, struct task_struct *p, + bool wakeup) {} +static inline void psi_dequeue(struct rq *rq, struct task_struct *p, + bool sleep) {} +static inline void psi_ttwu_dequeue(struct task_struct *p) {} +#endif /* CONFIG_PSI */ + #ifdef CONFIG_SCHED_INFO static inline void sched_info_reset_dequeued(struct task_struct *t) { diff --git a/mm/compaction.c b/mm/compaction.c index 29bd1df18b98..8f9566745902 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -22,6 +22,7 @@ #include #include #include +#include #include "internal.h" #ifdef CONFIG_COMPACTION @@ -2068,11 +2069,15 @@ static int kcompactd(void *p) pgdat->kcompactd_classzone_idx = pgdat->nr_zones - 1; while (!kthread_should_stop()) { + unsigned long pflags; + trace_mm_compaction_kcompactd_sleep(pgdat->node_id); wait_event_freezable(pgdat->kcompactd_wait, kcompactd_work_requested(pgdat)); + psi_memstall_enter(&pflags); kcompactd_do_work(pgdat); + psi_memstall_leave(&pflags); } return 0; diff --git a/mm/filemap.c b/mm/filemap.c index e49961e13dd9..eee06145b997 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -37,6 +37,7 @@ #include #include #include +#include #include "internal.h" #define CREATE_TRACE_POINTS @@ -1075,11 +1076,14 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q, struct wait_page_queue wait_page; wait_queue_entry_t *wait = &wait_page.wait; bool thrashing = false; + unsigned long pflags; int ret = 0; - if (bit_nr == PG_locked && !PageSwapBacked(page) && + if (bit_nr == PG_locked && !PageUptodate(page) && PageWorkingset(page)) { - delayacct_thrashing_start(); + if (!PageSwapBacked(page)) + delayacct_thrashing_start(); + psi_memstall_enter(&pflags); thrashing = true; } @@ -1121,8 +1125,11 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q, finish_wait(q, wait); - if (thrashing) - delayacct_thrashing_end(); + if (thrashing) { + if (!PageSwapBacked(page)) + delayacct_thrashing_end(); + psi_memstall_leave(&pflags); + } /* * A signal could leave PageWaiters set. Clearing it here if diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 22320ea27489..8469f34e6731 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -67,6 +67,7 @@ #include #include #include +#include #include #include @@ -3552,15 +3553,20 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, enum compact_priority prio, enum compact_result *compact_result) { struct page *page; + unsigned long pflags; unsigned int noreclaim_flag; if (!order) return NULL; + psi_memstall_enter(&pflags); noreclaim_flag = memalloc_noreclaim_save(); + *compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac, prio); + memalloc_noreclaim_restore(noreclaim_flag); + psi_memstall_leave(&pflags); if (*compact_result <= COMPACT_INACTIVE) return NULL; @@ -3749,11 +3755,14 @@ __perform_reclaim(gfp_t gfp_mask, unsigned int order, struct reclaim_state reclaim_state; int progress; unsigned int noreclaim_flag; + unsigned long pflags; cond_resched(); /* We now go into synchronous reclaim */ cpuset_memory_pressure_bump(); + + psi_memstall_enter(&pflags); noreclaim_flag = memalloc_noreclaim_save(); fs_reclaim_acquire(gfp_mask); reclaim_state.reclaimed_slab = 0; @@ -3765,6 +3774,7 @@ __perform_reclaim(gfp_t gfp_mask, unsigned int order, current->reclaim_state = NULL; fs_reclaim_release(gfp_mask); memalloc_noreclaim_restore(noreclaim_flag); + psi_memstall_leave(&pflags); cond_resched(); diff --git a/mm/vmscan.c b/mm/vmscan.c index 8d1ad48ffbcd..ee91e8cbeb5a 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -49,6 +49,7 @@ #include #include #include +#include #include #include @@ -3115,6 +3116,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, { struct zonelist *zonelist; unsigned long nr_reclaimed; + unsigned long pflags; int nid; unsigned int noreclaim_flag; struct scan_control sc = { @@ -3143,9 +3145,13 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, sc.gfp_mask, sc.reclaim_idx); + psi_memstall_enter(&pflags); noreclaim_flag = memalloc_noreclaim_save(); + nr_reclaimed = do_try_to_free_pages(zonelist, &sc); + memalloc_noreclaim_restore(noreclaim_flag); + psi_memstall_leave(&pflags); trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed); @@ -3565,6 +3571,7 @@ static int kswapd(void *p) pgdat->kswapd_order = 0; pgdat->kswapd_classzone_idx = MAX_NR_ZONES; for ( ; ; ) { + unsigned long pflags; bool ret; alloc_order = reclaim_order = pgdat->kswapd_order; @@ -3601,9 +3608,15 @@ static int kswapd(void *p) */ trace_mm_vmscan_kswapd_wake(pgdat->node_id, classzone_idx, alloc_order); + + psi_memstall_enter(&pflags); fs_reclaim_acquire(GFP_KERNEL); + reclaim_order = balance_pgdat(pgdat, alloc_order, classzone_idx); + fs_reclaim_release(GFP_KERNEL); + psi_memstall_leave(&pflags); + if (reclaim_order < alloc_order) goto kswapd_try_sleep; } From patchwork Wed Aug 1 15:19:58 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10552473 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2679915E9 for ; Wed, 1 Aug 2018 15:17:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 16C1A2ACA2 for ; Wed, 1 Aug 2018 15:17:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 094D02ACBC; Wed, 1 Aug 2018 15:17:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F3E9C2ACA2 for ; Wed, 1 Aug 2018 15:17:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2086F6B0286; Wed, 1 Aug 2018 11:17:46 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 1B8E26B0287; Wed, 1 Aug 2018 11:17:46 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 05C4D6B0289; Wed, 1 Aug 2018 11:17:45 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-qk0-f199.google.com (mail-qk0-f199.google.com [209.85.220.199]) by kanga.kvack.org (Postfix) with ESMTP id C4AB96B0287 for ; Wed, 1 Aug 2018 11:17:45 -0400 (EDT) Received: by mail-qk0-f199.google.com with SMTP id y130-v6so17255743qka.1 for ; Wed, 01 Aug 2018 08:17:45 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=td8sVEq7B3zRpddgZoElV+O4+/3RnsPaR9Zy76qVrWc=; b=NY4hIoIUKG8+da9MVvxjE19YfyPLeaVy5wqZ+nFfQq8hXv3LCg4M6LVy0gRpy27RJu E68ClCFeB4ghMcAKxzcdArgHM/eONc5puzc0jFKP82K2B7Id1fkCwhuWojgdL/UhrP1t e2E+kVzs+AICa+p2lO87aH4vc0dwMgVnF8YfZ3iE0gTiNHAETbcc2K7xr1v/x0ld50X4 ImaFZ+rlXYUC+m4Bu8mA9gHk4SMebA6cWHmwaMdqhtPf1GxSgC40pTcUgdqTiFw1BLHj qFXu5iC60zMOg1Xj1TIqod13jr4xToEPuZCjgY0IU9TpoEf1B47398q3c/3C0S2BEp43 CcFQ== X-Gm-Message-State: AOUpUlGP+omQTZYT7Gn4k3c7VIUIhFXJJBXka8Ny7QKQ6BobAD6ZU9s6 e1kyCGJzC+pGVoaOeWsIvGrBcMvCXdbTJJt8Zom/rTKcYA10CPsm3dwyJGA1VSwPm438yj7cTYj mf6+2/dwSHHI/OLSxGebWeD8diiNr45Jfy5qRkj5qd1Yc6yGbyIptE+4840o41bjctI/j902FKv OxVITS4zR754TuxAbe0g8QasPKWWGpPrXvNNURLIFtU2D5mbGnEZ8EF1cFfARDmBYGa6IQcxT6N 1+jfN1woPZvY1QRjSf6uDGSXcSqMjz69PpFLGuSjBr/ry/kY4Ahs2HRc1q2D/XyglHLjzkXNRR3 QLcxMARSkEEwhKX9RDAmq0G75RRRtAxYutTY6JybXeqS/iVb8kwWi9JxMfjFww2w3ihiHK4nBTR U X-Received: by 2002:a37:2711:: with SMTP id n17-v6mr23623189qkn.109.1533136665481; Wed, 01 Aug 2018 08:17:45 -0700 (PDT) X-Received: by 2002:a37:2711:: with SMTP id n17-v6mr23623119qkn.109.1533136664458; Wed, 01 Aug 2018 08:17:44 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533136664; cv=none; d=google.com; s=arc-20160816; b=DJia2LiSLHBJtHiF4V244MZEV9uEeqcEWiANgMXdcGCcCBv33QKKgq38+8lMnglQnC ynlN0gbvLPVrxjy6mL61ziNJVIkml4z0ccz5mKdUj53g/R9iiJf/sku5gQ9gvQSkJIh3 0cWgjVb9EU+1GJAunHBjGriBE+jJZLz3madQCx4MNy+MTRy0jZHlL8AnD1J5jom0TPef BVCf84wo9nIqTkckMwyUNGcvKJvUeiTIK/v2CdXRkUjP9jpZzFPRmY/kTo+wqqtxMh2k N8tBCv1J16Cp4mFtVRax4mdtrMNbJcyksB00vrQGlLC/npQaohEYmy/y3NKbDFJjOZ2U VBwQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=td8sVEq7B3zRpddgZoElV+O4+/3RnsPaR9Zy76qVrWc=; b=VFu42kqqPb0dDYSGibWRRkyz8pKGe+pDSr/BZN5A3NphOOtwgVQzOHTGA1eaV8m9oX JGtVL7mTNpfJXgH0M4Bd26Kr/4iH/SEuPGlUfYuOM6LxcuFh3UrLM3SgkUZ+41V+lRZ3 3/iVoN/iQPsei61NavH7uwSO7LBzhgAVx6dRYZDwVfphyFg+mGw00KBUmU1SV1luHHie swYCbK+xkLrecPhmb3SwjI0KCJAkQVO+igowLrdMtSTZcTgmF/atAlv9bUeTegA/a2vK qNLec94i+GlUvVaTvXAfbgTFO9On5j6r1dXd1h/YMcq9PfeTK2t64scD6MfbwxObNOE9 1BQQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=KL9Kw381; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id z11-v6sor9254252qti.109.2018.08.01.08.17.44 for (Google Transport Security); Wed, 01 Aug 2018 08:17:44 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=KL9Kw381; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=td8sVEq7B3zRpddgZoElV+O4+/3RnsPaR9Zy76qVrWc=; b=KL9Kw381RFpnCLgDoWqIx1BR1NJDAptWxyqx03S6uawYslq4CKGBtWzF0Ih4PK519W msUTCi4DSh35e+wZGcM/GIu0haSYPvTc9ZmFjklrpaTBXShCHT/oqaA3UI57uigLOLrY RwgrZ5WlvxWUcp4bfk2R/pOtj8ScNj9XqOi0vjAccEUSe/f7bkceysqpIgkOdogH3Tgg ZbNfGItmz8Wy/FS0WTRjhh8mxr0jqiu5Bn4tzFzqncBdPhIXFUFhEPMG7CpBwMLLhI8V Ph0pitoppIirCVzVOwNTzB9R8MGHTDqkDMzp5Owm+58ggB0PkeAy1IsHMneC1FpIQN5+ /qrA== X-Google-Smtp-Source: AAOMgpfyin81rAClyoUowtUsN3pTO+9hDyRNQFZ89szGm2n+DcXpuwg6L0RkPia6xfvysbyo2Fj0Xg== X-Received: by 2002:ac8:489:: with SMTP id s9-v6mr25479578qtg.173.1533136663941; Wed, 01 Aug 2018 08:17:43 -0700 (PDT) Received: from localhost (216.49.36.201.res-cmts.bus.ptd.net. [216.49.36.201]) by smtp.gmail.com with ESMTPSA id 49-v6sm12027407qtz.43.2018.08.01.08.17.42 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 01 Aug 2018 08:17:42 -0700 (PDT) From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Daniel Drake , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , Peter Enderborg , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 9/9] psi: cgroup support Date: Wed, 1 Aug 2018 11:19:58 -0400 Message-Id: <20180801151958.32590-10-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180801151958.32590-1-hannes@cmpxchg.org> References: <20180801151958.32590-1-hannes@cmpxchg.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP On a system that executes multiple cgrouped jobs and independent workloads, we don't just care about the health of the overall system, but also that of individual jobs, so that we can ensure individual job health, fairness between jobs, or prioritize some jobs over others. This patch implements pressure stall tracking for cgroups. In kernels with CONFIG_PSI=y, cgroup2 groups will have cpu.pressure, memory.pressure, and io.pressure files that track aggregate pressure stall times for only the tasks inside the cgroup. v3: - fix copy-paste indentation screwups Acked-by: Tejun Heo Signed-off-by: Johannes Weiner --- Documentation/accounting/psi.txt | 9 ++++ Documentation/cgroup-v2.txt | 18 +++++++ include/linux/cgroup-defs.h | 4 ++ include/linux/cgroup.h | 15 ++++++ include/linux/psi.h | 25 ++++++++++ init/Kconfig | 4 ++ kernel/cgroup/cgroup.c | 45 +++++++++++++++++- kernel/sched/psi.c | 81 +++++++++++++++++++++++++++++++- 8 files changed, 197 insertions(+), 4 deletions(-) diff --git a/Documentation/accounting/psi.txt b/Documentation/accounting/psi.txt index 51e7ef14142e..e051810d5127 100644 --- a/Documentation/accounting/psi.txt +++ b/Documentation/accounting/psi.txt @@ -62,3 +62,12 @@ well as medium and long term trends. The total absolute stall time is tracked and exported as well, to allow detection of latency spikes which wouldn't necessarily make a dent in the time averages, or to average trends over custom time frames. + +Cgroup2 interface +================= + +In a system with a CONFIG_CGROUP=y kernel and the cgroup2 filesystem +mounted, pressure stall information is also tracked for tasks grouped +into cgroups. Each subdirectory in the cgroupfs mountpoint contains +cpu.pressure, memory.pressure, and io.pressure files; the format is +the same as the /proc/pressure/ files. diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt index 74cdeaed9f7a..a22879dba019 100644 --- a/Documentation/cgroup-v2.txt +++ b/Documentation/cgroup-v2.txt @@ -963,6 +963,12 @@ All time durations are in microseconds. $PERIOD duration. "max" for $MAX indicates no limit. If only one number is written, $MAX is updated. + cpu.pressure + A read-only nested-key file which exists on non-root cgroups. + + Shows pressure stall information for CPU. See + Documentation/accounting/psi.txt for details. + Memory ------ @@ -1199,6 +1205,12 @@ PAGE_SIZE multiple when read back. Swap usage hard limit. If a cgroup's swap usage reaches this limit, anonymous memory of the cgroup will not be swapped out. + memory.pressure + A read-only nested-key file which exists on non-root cgroups. + + Shows pressure stall information for memory. See + Documentation/accounting/psi.txt for details. + Usage Guidelines ~~~~~~~~~~~~~~~~ @@ -1334,6 +1346,12 @@ IO Interface Files 8:16 rbps=2097152 wbps=max riops=max wiops=max + io.pressure + A read-only nested-key file which exists on non-root cgroups. + + Shows pressure stall information for IO. See + Documentation/accounting/psi.txt for details. + Writeback ~~~~~~~~~ diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index dc5b70449dc6..280f18da956a 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -20,6 +20,7 @@ #include #include #include +#include #ifdef CONFIG_CGROUPS @@ -424,6 +425,9 @@ struct cgroup { /* used to schedule release agent */ struct work_struct release_agent_work; + /* used to track pressure stalls */ + struct psi_group psi; + /* used to store eBPF programs */ struct cgroup_bpf bpf; diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 473e0c0abb86..fd94c294c207 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -627,6 +627,11 @@ static inline void pr_cont_cgroup_path(struct cgroup *cgrp) pr_cont_kernfs_path(cgrp->kn); } +static inline struct psi_group *cgroup_psi(struct cgroup *cgrp) +{ + return &cgrp->psi; +} + static inline void cgroup_init_kthreadd(void) { /* @@ -680,6 +685,16 @@ static inline union kernfs_node_id *cgroup_get_kernfs_id(struct cgroup *cgrp) return NULL; } +static inline struct cgroup *cgroup_parent(struct cgroup *cgrp) +{ + return NULL; +} + +static inline struct psi_group *cgroup_psi(struct cgroup *cgrp) +{ + return NULL; +} + static inline bool task_under_cgroup_hierarchy(struct task_struct *task, struct cgroup *ancestor) { diff --git a/include/linux/psi.h b/include/linux/psi.h index 371af1479699..05c3dae3e9c5 100644 --- a/include/linux/psi.h +++ b/include/linux/psi.h @@ -4,6 +4,9 @@ #include #include +struct seq_file; +struct css_set; + #ifdef CONFIG_PSI extern bool psi_disabled; @@ -15,6 +18,14 @@ void psi_task_change(struct task_struct *task, u64 now, int clear, int set); void psi_memstall_enter(unsigned long *flags); void psi_memstall_leave(unsigned long *flags); +int psi_show(struct seq_file *s, struct psi_group *group, enum psi_res res); + +#ifdef CONFIG_CGROUPS +int psi_cgroup_alloc(struct cgroup *cgrp); +void psi_cgroup_free(struct cgroup *cgrp); +void cgroup_move_task(struct task_struct *p, struct css_set *to); +#endif + #else /* CONFIG_PSI */ static inline void psi_init(void) {} @@ -22,6 +33,20 @@ static inline void psi_init(void) {} static inline void psi_memstall_enter(unsigned long *flags) {} static inline void psi_memstall_leave(unsigned long *flags) {} +#ifdef CONFIG_CGROUPS +static inline int psi_cgroup_alloc(struct cgroup *cgrp) +{ + return 0; +} +static inline void psi_cgroup_free(struct cgroup *cgrp) +{ +} +static inline void cgroup_move_task(struct task_struct *p, struct css_set *to) +{ + rcu_assign_pointer(p->cgroups, to); +} +#endif + #endif /* CONFIG_PSI */ #endif /* _LINUX_PSI_H */ diff --git a/init/Kconfig b/init/Kconfig index ad61ddb5d68e..5c029f8d69f1 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -468,6 +468,10 @@ config PSI the share of walltime in which some or all tasks in the system are delayed due to contention of the respective resource. + In kernels with cgroup support (cgroup2 only), cgroups will + have cpu.pressure, memory.pressure, and io.pressure files, + which aggregate pressure stalls for the grouped tasks only. + For more details see Documentation/accounting/psi.txt. Say N if unsure. diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index a662bfcbea0e..bbb00b3ab752 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -54,6 +54,7 @@ #include #include #include +#include #include #define CREATE_TRACE_POINTS @@ -826,7 +827,7 @@ static void css_set_move_task(struct task_struct *task, */ WARN_ON_ONCE(task->flags & PF_EXITING); - rcu_assign_pointer(task->cgroups, to_cset); + cgroup_move_task(task, to_cset); list_add_tail(&task->cg_list, use_mg_tasks ? &to_cset->mg_tasks : &to_cset->tasks); } @@ -3388,6 +3389,21 @@ static int cpu_stat_show(struct seq_file *seq, void *v) return ret; } +#ifdef CONFIG_PSI +static int cgroup_io_pressure_show(struct seq_file *seq, void *v) +{ + return psi_show(seq, &seq_css(seq)->cgroup->psi, PSI_IO); +} +static int cgroup_memory_pressure_show(struct seq_file *seq, void *v) +{ + return psi_show(seq, &seq_css(seq)->cgroup->psi, PSI_MEM); +} +static int cgroup_cpu_pressure_show(struct seq_file *seq, void *v) +{ + return psi_show(seq, &seq_css(seq)->cgroup->psi, PSI_CPU); +} +#endif + static int cgroup_file_open(struct kernfs_open_file *of) { struct cftype *cft = of->kn->priv; @@ -4499,6 +4515,23 @@ static struct cftype cgroup_base_files[] = { .flags = CFTYPE_NOT_ON_ROOT, .seq_show = cpu_stat_show, }, +#ifdef CONFIG_PSI + { + .name = "io.pressure", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = cgroup_io_pressure_show, + }, + { + .name = "memory.pressure", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = cgroup_memory_pressure_show, + }, + { + .name = "cpu.pressure", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = cgroup_cpu_pressure_show, + }, +#endif { } /* terminate */ }; @@ -4559,6 +4592,7 @@ static void css_free_rwork_fn(struct work_struct *work) */ cgroup_put(cgroup_parent(cgrp)); kernfs_put(cgrp->kn); + psi_cgroup_free(cgrp); if (cgroup_on_dfl(cgrp)) cgroup_stat_exit(cgrp); kfree(cgrp); @@ -4805,10 +4839,15 @@ static struct cgroup *cgroup_create(struct cgroup *parent) cgrp->self.parent = &parent->self; cgrp->root = root; cgrp->level = level; - ret = cgroup_bpf_inherit(cgrp); + + ret = psi_cgroup_alloc(cgrp); if (ret) goto out_idr_free; + ret = cgroup_bpf_inherit(cgrp); + if (ret) + goto out_psi_free; + for (tcgrp = cgrp; tcgrp; tcgrp = cgroup_parent(tcgrp)) { cgrp->ancestor_ids[tcgrp->level] = tcgrp->id; @@ -4846,6 +4885,8 @@ static struct cgroup *cgroup_create(struct cgroup *parent) return cgrp; +out_psi_free: + psi_cgroup_free(cgrp); out_idr_free: cgroup_idr_remove(&root->cgroup_idr, cgrp->id); out_stat_exit: diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index 57ec86592b5a..a20f885da66f 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -464,6 +464,9 @@ static void psi_group_change(struct psi_group *group, int cpu, u64 now, void psi_task_change(struct task_struct *task, u64 now, int clear, int set) { +#ifdef CONFIG_CGROUPS + struct cgroup *cgroup, *parent; +#endif int cpu = task_cpu(task); if (psi_disabled) @@ -485,6 +488,18 @@ void psi_task_change(struct task_struct *task, u64 now, int clear, int set) task->psi_flags |= set; psi_group_change(&psi_system, cpu, now, clear, set); + +#ifdef CONFIG_CGROUPS + cgroup = task->cgroups->dfl_cgrp; + while (cgroup && (parent = cgroup_parent(cgroup))) { + struct psi_group *group; + + group = cgroup_psi(cgroup); + psi_group_change(group, cpu, now, clear, set); + + cgroup = parent; + } +#endif } /** @@ -551,8 +566,70 @@ void psi_memstall_leave(unsigned long *flags) rq_unlock_irq(rq, &rf); } -static int psi_show(struct seq_file *m, struct psi_group *group, - enum psi_res res) +#ifdef CONFIG_CGROUPS +int psi_cgroup_alloc(struct cgroup *cgroup) +{ + cgroup->psi.pcpu = alloc_percpu(struct psi_group_cpu); + if (!cgroup->psi.pcpu) + return -ENOMEM; + psi_group_init(&cgroup->psi); + return 0; +} + +void psi_cgroup_free(struct cgroup *cgroup) +{ + cancel_delayed_work_sync(&cgroup->psi.clock_work); + free_percpu(cgroup->psi.pcpu); +} + +/** + * cgroup_move_task - move task to a different cgroup + * @task: the task + * @to: the target css_set + * + * Move task to a new cgroup and safely migrate its associated stall + * state between the different groups. + * + * This function acquires the task's rq lock to lock out concurrent + * changes to the task's scheduling state and - in case the task is + * running - concurrent changes to its stall state. + */ +void cgroup_move_task(struct task_struct *task, struct css_set *to) +{ + unsigned int task_flags = 0; + struct rq_flags rf; + struct rq *rq; + u64 now; + + rq = task_rq_lock(task, &rf); + + if (task_on_rq_queued(task)) + task_flags = TSK_RUNNING; + else if (task->in_iowait) + task_flags = TSK_IOWAIT; + if (task->flags & PF_MEMSTALL) + task_flags |= TSK_MEMSTALL; + + if (task_flags) { + update_rq_clock(rq); + now = rq_clock(rq); + psi_task_change(task, now, task_flags, 0); + } + + /* + * Lame to do this here, but the scheduler cannot be locked + * from the outside, so we move cgroups from inside sched/. + */ + rcu_assign_pointer(task->cgroups, to); + + if (task_flags) + psi_task_change(task, now, 0, task_flags); + + task_rq_unlock(rq, task, &rf); +} +#endif /* CONFIG_CGROUPS */ + +int psi_show(struct seq_file *m, struct psi_group *group, enum psi_res res) { int full;