From patchwork Tue Apr 28 16:13:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Schatzberg X-Patchwork-Id: 11515043 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5E4D581 for ; Tue, 28 Apr 2020 16:15:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 45D262054F for ; Tue, 28 Apr 2020 16:15:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="E4MNL14Q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728130AbgD1QPu (ORCPT ); Tue, 28 Apr 2020 12:15:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728110AbgD1QPt (ORCPT ); Tue, 28 Apr 2020 12:15:49 -0400 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8FF69C03C1AB; Tue, 28 Apr 2020 09:15:49 -0700 (PDT) Received: by mail-qt1-x841.google.com with SMTP id k12so17777521qtm.4; Tue, 28 Apr 2020 09:15:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=1xs7a52HdDCbAExnqSe5+2K/TyJ01Rp0raQ7acG2FHw=; b=E4MNL14QuXFKvfZICzfj5fNhzPIifsriRq/F4PIrWZFWcsdAhA7+/0YMPNgMymNaup Xg5cg+/uTHi/B1cn3qqVTK3lQc8Fex5a7ttpahrChGEv0NsDnZ4too1jWJHNnXLNQw+R +iIYvu469MXtSxA1M9cd1XTQJES2bzg+0+aYhm3AuODTvkB0BftZvOTYOUJ5I+moLZlK RX9FbMcKmqfsgmvdKYefTFWyw9fWZK5ZyZgo/276pUXQvXnStHGF+au3idehdV+SDLTb NR9+2WD3an1OkNxpAH9PFODMjWySx36OGCQynoDU89LYMeGLBeeZDUI1vcybRjj3gp7a 6vYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=1xs7a52HdDCbAExnqSe5+2K/TyJ01Rp0raQ7acG2FHw=; b=Yi9dZU1AWEpbUsRwwmsVMOx/SR2Bf9sNZFKZpHKQuDJ9S9t8dAZAmf2Dhj/BadTTkr HacSznF94sILpNHs0ls08zhqHoxLZdbZ/2/3Qmj4oi3UW1BGqQYBBtSX0PFJiOyMdobq hVbpi/wiUwPwEu8LoZv8t5Re0L3G6ThYu7bVIEsKISs+oIckoxOSu4VXgJmrbY3zz6hv FJ+cuwSIM3tetOIAiVBBFF/wqvzr41xbfy43qhOLaE77rY50JcLjtvvY/KQ2CpsxwvKO N6KJ0/b1O8DWZuC2jYgm+MfMkSsnymbgurG3BD+7PZICJzc8LkiuMnDs5LB8efi0URZv AxiA== X-Gm-Message-State: AGi0PuZOO3aBzklSKbrdSeEXVpaZj0DDNV/NH/JC7zdqSuDN/asS+ND+ Z51DolismgrjxN6HZdwx3K0= X-Google-Smtp-Source: APiQypJFFiv9OaV70OkM1q6yEZ+bOU61wDnKK2elgNnOimCvruyN6mVSWyM2pRgW9YZjXC8EhevipA== X-Received: by 2002:aed:233d:: with SMTP id h58mr26062944qtc.4.1588090547337; Tue, 28 Apr 2020 09:15:47 -0700 (PDT) Received: from dschatzberg-fedora-PC0Y6AEN.thefacebook.com ([2620:10d:c091:480::1:3e4a]) by smtp.gmail.com with ESMTPSA id z2sm14087421qkc.28.2020.04.28.09.15.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Apr 2020 09:15:46 -0700 (PDT) From: Dan Schatzberg Cc: Dan Schatzberg , Johannes Weiner , Tejun Heo , Chris Down , Shakeel Butt , Jens Axboe , Alexander Viro , Jan Kara , Amir Goldstein , Li Zefan , Michal Hocko , Vladimir Davydov , Andrew Morton , Hugh Dickins , Roman Gushchin , Yang Shi , "Peter Zijlstra (Intel)" , Ingo Molnar , Mathieu Desnoyers , "Kirill A. Shutemov" , Andrea Arcangeli , Thomas Gleixner , linux-block@vger.kernel.org (open list:BLOCK LAYER), linux-kernel@vger.kernel.org (open list), linux-fsdevel@vger.kernel.org (open list:FILESYSTEMS (VFS and infrastructure)), cgroups@vger.kernel.org (open list:CONTROL GROUP (CGROUP)), linux-mm@kvack.org (open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)) Subject: [PATCH v5 3/4] mm: Charge active memcg when no mm is set Date: Tue, 28 Apr 2020 12:13:49 -0400 Message-Id: <20200428161355.6377-4-schatzberg.dan@gmail.com> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200428161355.6377-1-schatzberg.dan@gmail.com> References: <20200428161355.6377-1-schatzberg.dan@gmail.com> MIME-Version: 1.0 To: unlisted-recipients:; (no To-header on input) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org memalloc_use_memcg() worked for kernel allocations but was silently ignored for user pages. This patch establishes a precedence order for who gets charged: 1. If there is a memcg associated with the page already, that memcg is charged. This happens during swapin. 2. If an explicit mm is passed, mm->memcg is charged. This happens during page faults, which can be triggered in remote VMs (eg gup). 3. Otherwise consult the current process context. If it has configured a current->active_memcg, use that. Otherwise, current->mm->memcg. Previously, if a NULL mm was passed to mem_cgroup_try_charge (case 3) it would always charge the root cgroup. Now it looks up the current active_memcg first (falling back to charging the root cgroup if not set). Signed-off-by: Dan Schatzberg Acked-by: Johannes Weiner Acked-by: Tejun Heo Acked-by: Chris Down Reviewed-by: Shakeel Butt --- mm/memcontrol.c | 11 ++++++++--- mm/shmem.c | 4 ++-- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5beea03dd58a..af68d1d7b456 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6435,7 +6435,8 @@ enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root, * @compound: charge the page as compound or small page * * Try to charge @page to the memcg that @mm belongs to, reclaiming - * pages according to @gfp_mask if necessary. + * pages according to @gfp_mask if necessary. if @mm is NULL, try to + * charge to the active memcg. * * Returns 0 on success, with *@memcgp pointing to the charged memcg. * Otherwise, an error code is returned. @@ -6479,8 +6480,12 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, } } - if (!memcg) - memcg = get_mem_cgroup_from_mm(mm); + if (!memcg) { + if (!mm) + memcg = get_mem_cgroup_from_current(); + else + memcg = get_mem_cgroup_from_mm(mm); + } ret = try_charge(memcg, gfp_mask, nr_pages); diff --git a/mm/shmem.c b/mm/shmem.c index d722eb830317..8c8ffc35a957 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1618,7 +1618,7 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index, { struct address_space *mapping = inode->i_mapping; struct shmem_inode_info *info = SHMEM_I(inode); - struct mm_struct *charge_mm = vma ? vma->vm_mm : current->mm; + struct mm_struct *charge_mm = vma ? vma->vm_mm : NULL; struct mem_cgroup *memcg; struct page *page; swp_entry_t swap; @@ -1753,7 +1753,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, } sbinfo = SHMEM_SB(inode->i_sb); - charge_mm = vma ? vma->vm_mm : current->mm; + charge_mm = vma ? vma->vm_mm : NULL; page = find_lock_entry(mapping, index); if (xa_is_value(page)) {