From patchwork Mon Aug 8 16:50:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Geffon X-Patchwork-Id: 12938896 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0991C00140 for ; Mon, 8 Aug 2022 16:50:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2E5878E0001; Mon, 8 Aug 2022 12:50:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2955E6B0072; Mon, 8 Aug 2022 12:50:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 15D1F8E0001; Mon, 8 Aug 2022 12:50:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 04A8F6B0071 for ; Mon, 8 Aug 2022 12:50:18 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id CA0BA1C6657 for ; Mon, 8 Aug 2022 16:50:17 +0000 (UTC) X-FDA: 79777013274.01.E4A01D9 Received: from mail-il1-f201.google.com (mail-il1-f201.google.com [209.85.166.201]) by imf21.hostedemail.com (Postfix) with ESMTP id 544F01C0193 for ; Mon, 8 Aug 2022 16:50:17 +0000 (UTC) Received: by mail-il1-f201.google.com with SMTP id d6-20020a056e020be600b002dcc7977592so6879600ilu.17 for ; Mon, 08 Aug 2022 09:50:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:from:to:cc; bh=zLBaz1rNilIGO1w+9okx/7wDlrqzaB/ECodczQmMqDg=; b=SXN40bs60VueldknoEZRL/zUqMBFiRjOvb4xJhRznmyY/q9g2eYGWHAywR4iPzWBdZ jYKk6cgBVhi18CnymR5cBw1u5UnUUNBsuPV5fwvHrbBChNADVsHh/qwt8qIaYv875CFj QxHnBSC6kAsq6SXAQg6Xm/SBtu2+b5suCjkT86tKVQ9Wu3qIR9SNNMyXXO+T4oR0HaB1 XGEQshCSROF00CTXxEUQoFbTVa2spaxjgM4pgrv9vtZK75OrpIuRtMh45v11QTpnLh1i ILJWSq6H2brclpmghkvHvAHIcViBO9laXfCpJ7tST+Jv1a3XlJuL4F8T/7sg4plu94GE GNcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:x-gm-message-state :from:to:cc; bh=zLBaz1rNilIGO1w+9okx/7wDlrqzaB/ECodczQmMqDg=; b=o6BECymKajt7TgQkSdlDaY9lv0KCbD0oKhX4mMcu3Qe+UVkcI7Fz8zhC9g29zHfv5M D6NCkyTcLdqqrkNWj6m5RYc9ejv4vsTvi1s6ASWIWrQHbR3gberQef1p/0TgJ2Nj+U0L m2McO/CQcNTFBbaEMTaO82nKXEeUi20Wa81TVY8xDelAhgVLZqj9pvu2VX4XzXsAjuWf twy9BDbjnsqLJky7wOODXPQ5xv3mEnaYPXQLiJ4cWRHbdl1Hd83yG7uFb+/NRb6Za0Wc UUnMww+Ck8LDoBE29pis+GBCp3BNacjvwoXIO5Nl3/W0pc/JijCgbdEZLYXwaH2GIH1e CD7g== X-Gm-Message-State: ACgBeo2ty9LHRYtYJJRPg5HTESIuXXeDWIenUIwIkgqS1RCYK5ED4O23 mmgXBs/V7S+FX55jUWYNb2xD3gi0WEvv X-Google-Smtp-Source: AA6agR6rGaBdFqljWoc2AjWrgUPT0W1bS8nnDdpxj9ZrEccxsyQk44igzgunmGfT413qVkMCkZ2lcPed54ro X-Received: from bg.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:1b4]) (user=bgeffon job=sendgmr) by 2002:a05:6e02:1caf:b0:2e0:cec1:9f17 with SMTP id x15-20020a056e021caf00b002e0cec19f17mr4074872ill.5.1659977416534; Mon, 08 Aug 2022 09:50:16 -0700 (PDT) Date: Mon, 8 Aug 2022 12:50:05 -0400 Message-Id: <20220808165006.2451180-1-bgeffon@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.37.1.559.g78731f0fdb-goog Subject: [RFC PATCH 0/1] zram: Allow rw_page when page isn't written back. From: Brian Geffon To: Andrew Morton , Minchan Kim Cc: Nitin Gupta , Sergey Senozhatsky , linux-kernel@vger.kernel.org, Suleiman Souhlal , linux-mm@kvack.org, Brian Geffon ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1659977417; a=rsa-sha256; cv=none; b=GhhhIT9tyUzbMMfQ5VLwfzii+wyVu0dDonjFXxv/LmRAObt7w4nGh8o00e6z5gY43YQomk pcHxZtJafK/wAkDqk4oPLlY0E1tDkPW7P4fbtlU7G2PF9cSRnDEgeXr9uMXqIeZHC4GtPX e03So6my4xRRh+rzp1C3nnGpLLiGOw8= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=SXN40bs6; spf=pass (imf21.hostedemail.com: domain of 3yD7xYgcKCCkGLJKKTSLTTLQJ.HTRQNSZc-RRPaFHP.TWL@flex--bgeffon.bounces.google.com designates 209.85.166.201 as permitted sender) smtp.mailfrom=3yD7xYgcKCCkGLJKKTSLTTLQJ.HTRQNSZc-RRPaFHP.TWL@flex--bgeffon.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1659977417; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding:in-reply-to: references:dkim-signature; bh=zLBaz1rNilIGO1w+9okx/7wDlrqzaB/ECodczQmMqDg=; b=JOXuxdtGA6A4onTom0qL2nrNwjzP+5WjiYBwDXNn40LEFGe+edaBfnPzwp8mS/SH0jTQSi Yw3KIJC9yMCmDjYsAk2BVpuIXE/+EoDT+rz5xTYU3Wwy8Ki1xjiSTJuvo3/5yOCu5HIdFO Xsv2HtK4ikZbL4TVl2QnnsrMJ05Uw5E= X-Stat-Signature: hb85cnrhjn9dbhp9qfuoogbeks16ok31 X-Rspamd-Queue-Id: 544F01C0193 Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=SXN40bs6; spf=pass (imf21.hostedemail.com: domain of 3yD7xYgcKCCkGLJKKTSLTTLQJ.HTRQNSZc-RRPaFHP.TWL@flex--bgeffon.bounces.google.com designates 209.85.166.201 as permitted sender) smtp.mailfrom=3yD7xYgcKCCkGLJKKTSLTTLQJ.HTRQNSZc-RRPaFHP.TWL@flex--bgeffon.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1659977417-392920 X-Bogosity: Ham, tests=bogofilter, spamicity=0.001344, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Today when a zram device has a backing device we change the ops to a new set which does not expose a rw_page method. This prevents the upper layers from trying to issue a synchronous rw. This has the downside that we penalize every rw even when it could possibly still be performed as a synchronous rw. This is just a proposal and I wanted to get feedback if people felt this was worthwhile. The motivation comes from what Minchan noted in the original change which introduced the synchronous behavior that it enhanches swap-in performance by about 45% [1]. So it'd be great if we could still get this benefit while using writeback. 1. https://lore.kernel.org/all/1505886205-9671-5-git-send-email-minchan@kernel.org/ Brian Geffon (1): zram: Allow rw_page when page isn't written back. drivers/block/zram/zram_drv.c | 65 +++++++++++++++++++++-------------- drivers/block/zram/zram_drv.h | 1 + 2 files changed, 41 insertions(+), 25 deletions(-)