From patchwork Thu Apr 13 10:40:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 13210087 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A69F5C77B6C for ; Thu, 13 Apr 2023 10:40:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230503AbjDMKkp (ORCPT ); Thu, 13 Apr 2023 06:40:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50722 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230327AbjDMKkl (ORCPT ); Thu, 13 Apr 2023 06:40:41 -0400 Received: from mail-pl1-x649.google.com (mail-pl1-x649.google.com [IPv6:2607:f8b0:4864:20::649]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 41AAE10EA for ; Thu, 13 Apr 2023 03:40:39 -0700 (PDT) Received: by mail-pl1-x649.google.com with SMTP id j2-20020a170902da8200b001a055243657so7994521plx.19 for ; Thu, 13 Apr 2023 03:40:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681382439; x=1683974439; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=xGnocY4pIBEOyCy1J5p5K30k0wCvlbaawbxDP+ACQr8=; b=7DaELoYbwDJCrNtZlmfg9Wt1StcR4uFr/DcPD/2pe3cLhlNGHN0Vo/cQ7EdPJo7up0 8bmCI0JQEmCL566Vot7ySRXaEZ0Q9wHFt3Sh9NvXD+gSBVNkrXxQorzAPrPz3sL21Jvg UkLNapMN9bhRXj3lO4/bDPz8UGmnAz0jlApmptNFgfyGVpKdYVctpDwfppNvGRrl4WXx hDn5QBpGHzMAOlfKXhd4xxjuLNGoae6rpvwcD9uDypxIntJ4NI1CR6tegrXbWE9t7vA4 LHSI7L2dX5euMSDWQaeHCt4S6p/b4GKxns2a9UeAtjH7MQxy0QVqfkDsaHQMGS5XAPuo 907w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681382439; x=1683974439; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=xGnocY4pIBEOyCy1J5p5K30k0wCvlbaawbxDP+ACQr8=; b=jklRdoixFu+X7tRVFNFcBoFi33TeCSKpg5d3I8MD3Ds1WEsCo3tvF6Y8Ffj3Skykjv sjqf+veFHLB/usx59CvTXiCzEsRn6+sqLqGtzIoKiazSZ84+S0pAIEQqbI+gW0SjT8sq 6HSI4e11MtmSjWWLQ0NzqNmiRa+mB9FS1mHNIICebcLhua828x9HBVEcZ01L4mjsAgTb K/XRe9zD+2QyH1z2ke8HcnrPWQjZzbbM7GOqq/K5cqnoDuz2uEChoeffG85SKGoFyh0F meHtBNEWv5zWclICc10/UG+TdemYjQPsV0y28kLWpcS+fUJTS+Jxz14jeQ46Vxjd65k5 WLfQ== X-Gm-Message-State: AAQBX9cm8KthU6tCBM9g/9VGCjTZQq7SUO/jaOOihnvgX7K+a0FBMyLS Q0UP4B83NaHM66QCDnjplUPoLp6JCwRSC4CB X-Google-Smtp-Source: AKy350a/CmtWydI2qt+GCIKlEW3m+RGe6OazzLUzw02C2znW4S1CHo0XCY6i4wYnjhyCBrNF8AH/yKwjvGLojZVt X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a65:51c7:0:b0:51a:f873:2645 with SMTP id i7-20020a6551c7000000b0051af8732645mr331971pgq.9.1681382438784; Thu, 13 Apr 2023 03:40:38 -0700 (PDT) Date: Thu, 13 Apr 2023 10:40:32 +0000 In-Reply-To: <20230413104034.1086717-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230413104034.1086717-1-yosryahmed@google.com> X-Mailer: git-send-email 2.40.0.577.gac1e443424-goog Message-ID: <20230413104034.1086717-2-yosryahmed@google.com> Subject: [PATCH v6 1/3] mm: vmscan: ignore non-LRU-based reclaim in memcg reclaim From: Yosry Ahmed To: Andrew Morton , Alexander Viro , "Darrick J. Wong" , Christoph Lameter , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, "Matthew Wilcox (Oracle)" , Miaohe Lin , David Hildenbrand , Johannes Weiner , Peter Xu , NeilBrown , Shakeel Butt , Michal Hocko , Yu Zhao , Dave Chinner , Tim Chen Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yosry Ahmed Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org We keep track of different types of reclaimed pages through reclaim_state->reclaimed_slab, and we add them to the reported number of reclaimed pages. For non-memcg reclaim, this makes sense. For memcg reclaim, we have no clue if those pages are charged to the memcg under reclaim. Slab pages are shared by different memcgs, so a freed slab page may have only been partially charged to the memcg under reclaim. The same goes for clean file pages from pruned inodes (on highmem systems) or xfs buffer pages, there is no simple way to currently link them to the memcg under reclaim. Stop reporting those freed pages as reclaimed pages during memcg reclaim. This should make the return value of writing to memory.reclaim, and may help reduce unnecessary reclaim retries during memcg charging. Writing to memory.reclaim on the root memcg is considered as cgroup_reclaim(), but for this case we want to include any freed pages, so use the global_reclaim() check instead of !cgroup_reclaim(). Generally, this should make the return value of try_to_free_mem_cgroup_pages() more accurate. In some limited cases (e.g. freed a slab page that was mostly charged to the memcg under reclaim), the return value of try_to_free_mem_cgroup_pages() can be underestimated, but this should be fine. The freed pages will be uncharged anyway, and we can charge the memcg the next time around as we usually do memcg reclaim in a retry loop. Fixes: f2fe7b09a52b ("mm: memcg/slab: charge individual slab objects instead of pages") Signed-off-by: Yosry Ahmed Acked-by: David Hildenbrand Acked-by: Michal Hocko --- mm/vmscan.c | 49 ++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 42 insertions(+), 7 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 9c1c5e8b24b8..be657832be48 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -511,6 +511,46 @@ static bool writeback_throttling_sane(struct scan_control *sc) } #endif +/* + * flush_reclaim_state(): add pages reclaimed outside of LRU-based reclaim to + * scan_control->nr_reclaimed. + */ +static void flush_reclaim_state(struct scan_control *sc) +{ + /* + * Currently, reclaim_state->reclaimed includes three types of pages + * freed outside of vmscan: + * (1) Slab pages. + * (2) Clean file pages from pruned inodes (on highmem systems). + * (3) XFS freed buffer pages. + * + * For all of these cases, we cannot universally link the pages to a + * single memcg. For example, a memcg-aware shrinker can free one object + * charged to the target memcg, causing an entire page to be freed. + * If we count the entire page as reclaimed from the memcg, we end up + * overestimating the reclaimed amount (potentially under-reclaiming). + * + * Only count such pages for global reclaim to prevent under-reclaiming + * from the target memcg; preventing unnecessary retries during memcg + * charging and false positives from proactive reclaim. + * + * For uncommon cases where the freed pages were actually mostly + * charged to the target memcg, we end up underestimating the reclaimed + * amount. This should be fine. The freed pages will be uncharged + * anyway, even if they are not counted here properly, and we will be + * able to make forward progress in charging (which is usually in a + * retry loop). + * + * We can go one step further, and report the uncharged objcg pages in + * memcg reclaim, to make reporting more accurate and reduce + * underestimation, but it's probably not worth the complexity for now. + */ + if (current->reclaim_state && global_reclaim(sc)) { + sc->nr_reclaimed += current->reclaim_state->reclaimed; + current->reclaim_state->reclaimed = 0; + } +} + static long xchg_nr_deferred(struct shrinker *shrinker, struct shrink_control *sc) { @@ -5346,8 +5386,7 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc) vmpressure(sc->gfp_mask, memcg, false, sc->nr_scanned - scanned, sc->nr_reclaimed - reclaimed); - sc->nr_reclaimed += current->reclaim_state->reclaimed_slab; - current->reclaim_state->reclaimed_slab = 0; + flush_reclaim_state(sc); return success ? MEMCG_LRU_YOUNG : 0; } @@ -6450,7 +6489,6 @@ static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc) static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) { - struct reclaim_state *reclaim_state = current->reclaim_state; unsigned long nr_reclaimed, nr_scanned; struct lruvec *target_lruvec; bool reclaimable = false; @@ -6472,10 +6510,7 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) shrink_node_memcgs(pgdat, sc); - if (reclaim_state) { - sc->nr_reclaimed += reclaim_state->reclaimed_slab; - reclaim_state->reclaimed_slab = 0; - } + flush_reclaim_state(sc); /* Record the subtree's reclaim efficiency */ if (!sc->proactive) From patchwork Thu Apr 13 10:40:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 13210088 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6629C77B76 for ; Thu, 13 Apr 2023 10:40:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230263AbjDMKkr (ORCPT ); Thu, 13 Apr 2023 06:40:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230385AbjDMKkm (ORCPT ); Thu, 13 Apr 2023 06:40:42 -0400 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11B081B6 for ; Thu, 13 Apr 2023 03:40:41 -0700 (PDT) Received: by mail-pf1-x44a.google.com with SMTP id d2e1a72fcca58-63b5a2099a6so26218b3a.3 for ; Thu, 13 Apr 2023 03:40:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681382440; x=1683974440; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=I6Nt0ZH454lLp6ex7hg7kbI+ex/azfnI8thXAXjWVq8=; b=G81CdUEmMWAR7s/uUh1o00+dki8yY8e8KOGduTMJ10Ih63YAx82qvcDq20SAZSx+g/ ueZ3Msj52pKD1lqBImwulf/tYkqr/iT+UOeW4fd3KBZv547W+MwD6xwGD67DaW0HpcOa cz9n6Ru3its9gZbaaSThe+VV0hYHOvVD9yp2j0yltd9IKliEUrjXqAr+OK7m03l2qytF xr+P3ML7/b+lezaU3DwMQukf+O+TPg5UG2i07gjQlaxwJnTBDRcJhvP64M/wiFfrpZzz h7ozlZBA7r8DTpqJhi25AoIblQhs+3bOV3uTp+JguZijEY3iI74Y975Ed/lYiOS4TnGE iVnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681382440; x=1683974440; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=I6Nt0ZH454lLp6ex7hg7kbI+ex/azfnI8thXAXjWVq8=; b=JBe9TTgiA5zq1lTwXhWh/4i/H1VcuyXviIdkD2dXr2Yv7KnymQzWmqs81C6t6vzyc+ BMXmQ0WmAf6X+C9PGG5BtJYwP7j5Ijun+8+nmtRins1jsTsdFIUeFXTGouOrHEsr1WIe Tk/azlKy2qD7ZMOuMrT1y2q+0owbeuTvMBWxspZEBcku8PQ9KgSiLPj0k9ZLuWIMaXTY qVxvNJF8lE9h2NtTNy8mElJ+OGOu0yJf9kQFfjbXWfoHRh0GHNPXlIcABQCHlv8S9r8t O1QEFdT1VRFLn0yRyAPrLKTdHgN/kLB/tm2S2G1geYb2Jyu+oCpiA13cATHR6PVPjlRn 31PQ== X-Gm-Message-State: AAQBX9e33xjdEkEQ7VBumt1lsPMa9cJ0Mzyw7SD90rhPCHx7CGKaoVBc oubJfUbrjAWlXWcILvIT89XDH6vIN5xzq6r1 X-Google-Smtp-Source: AKy350b4iSx5ozD7gi39VrWatA78FUtgnIqT2lDjsg7piXFtlDqLoC4lH3GhIMzW/GNCYSdmkQiW7wqZ38a9M/36 X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a05:6a00:2e1d:b0:63b:234e:d641 with SMTP id fc29-20020a056a002e1d00b0063b234ed641mr975833pfb.4.1681382440554; Thu, 13 Apr 2023 03:40:40 -0700 (PDT) Date: Thu, 13 Apr 2023 10:40:33 +0000 In-Reply-To: <20230413104034.1086717-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230413104034.1086717-1-yosryahmed@google.com> X-Mailer: git-send-email 2.40.0.577.gac1e443424-goog Message-ID: <20230413104034.1086717-3-yosryahmed@google.com> Subject: [PATCH v6 2/3] mm: vmscan: move set_task_reclaim_state() near flush_reclaim_state() From: Yosry Ahmed To: Andrew Morton , Alexander Viro , "Darrick J. Wong" , Christoph Lameter , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, "Matthew Wilcox (Oracle)" , Miaohe Lin , David Hildenbrand , Johannes Weiner , Peter Xu , NeilBrown , Shakeel Butt , Michal Hocko , Yu Zhao , Dave Chinner , Tim Chen Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yosry Ahmed Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Move set_task_reclaim_state() near flush_reclaim_state() so that all helpers manipulating reclaim_state are in close proximity. Signed-off-by: Yosry Ahmed Acked-by: Michal Hocko --- mm/vmscan.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index be657832be48..cb7d5a17c2b2 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -188,18 +188,6 @@ struct scan_control { */ int vm_swappiness = 60; -static void set_task_reclaim_state(struct task_struct *task, - struct reclaim_state *rs) -{ - /* Check for an overwrite */ - WARN_ON_ONCE(rs && task->reclaim_state); - - /* Check for the nulling of an already-nulled member */ - WARN_ON_ONCE(!rs && !task->reclaim_state); - - task->reclaim_state = rs; -} - LIST_HEAD(shrinker_list); DECLARE_RWSEM(shrinker_rwsem); @@ -511,6 +499,18 @@ static bool writeback_throttling_sane(struct scan_control *sc) } #endif +static void set_task_reclaim_state(struct task_struct *task, + struct reclaim_state *rs) +{ + /* Check for an overwrite */ + WARN_ON_ONCE(rs && task->reclaim_state); + + /* Check for the nulling of an already-nulled member */ + WARN_ON_ONCE(!rs && !task->reclaim_state); + + task->reclaim_state = rs; +} + /* * flush_reclaim_state(): add pages reclaimed outside of LRU-based reclaim to * scan_control->nr_reclaimed. From patchwork Thu Apr 13 10:40:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 13210089 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53B0DC77B6C for ; Thu, 13 Apr 2023 10:41:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231165AbjDMKlK (ORCPT ); Thu, 13 Apr 2023 06:41:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230502AbjDMKko (ORCPT ); Thu, 13 Apr 2023 06:40:44 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E07032D67 for ; Thu, 13 Apr 2023 03:40:42 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id h206-20020a2521d7000000b00b8f3681db1eso5584150ybh.11 for ; Thu, 13 Apr 2023 03:40:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681382442; x=1683974442; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=5OCAYSthWCELWDD+mYmXa9NvWHtbEH3UT/IFpudVmH4=; b=tNgjpd2vJ5sYdihexJ27wp/pJdtBdkGoDWlKPI+Qxip+uc94atiC4v8qSoBRSDpXnF 2H1eFR4AE43zDnf3vSAC6PM4Yzv5eOl4FnSZ87ySrNsQr00bC+1pP0q2NisEbs11XCfK wfmIAOuWTU7ukaHpLHwHLoguS2c0haEBvsc03OpVoC1wgoCMAvA/kO8UJucX9FKOKJPQ FUpRKC72wJ0M5aFsenyPyMH3rc7A+TUAdQgnGrgJs85bN23klJx4wsrqR1AZvj2NJaOn RSlnCkB73DeUMUXx2hJ8njcRovku/drtS2o23klZqkp9a4zr1WrXp8WQJA7orQxM0t6d M7ew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681382442; x=1683974442; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=5OCAYSthWCELWDD+mYmXa9NvWHtbEH3UT/IFpudVmH4=; b=GoiML+huCx6bDtWZqWUv8VMN+hj4jPC2l6PI5sDI3cNj9yjSRrHwEODs14RvrJczM2 zrRiVufsUyQ5831iCpfj6MEOAFKhACykscS1AislAylBpP8jl5/Sf2yucKr2F/mFO+JH v+jpazR3z6V0BN2SHYoNuhhF7MZFCv5TPSKNjgkWCn9tp1huR0FaBCJPJhow/sq/em26 UB8pDCvP0HtzDwFBBSWyUiFPynxosvF2EoDIQ4ThrOsC4l06mmkI5lSRc9CEZpRFFjIk VHrKe+M4b+GBuLwB7CQ5vVsUNIcxbe/CtBnbexoEwWh3pSt9VL7bj2vE38JvuoBc6ePg q7PA== X-Gm-Message-State: AAQBX9fLY5YWoaaJdhXZazyEZlUlBf9a0tD77reeQMlyQVnP+AeLM/di NyHEp22u70kp1XZvPaOZdH6A9jMU1SmyFjtJ X-Google-Smtp-Source: AKy350ato23F52bhKncBfpzqlbDSBjiTYHoOr/++AUIP1InXFnH0R1Cd3N+S/780qX9+qoWZd0rLQvVMvNIOlXzG X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a25:dad2:0:b0:ac9:cb97:bd0e with SMTP id n201-20020a25dad2000000b00ac9cb97bd0emr904171ybf.5.1681382442136; Thu, 13 Apr 2023 03:40:42 -0700 (PDT) Date: Thu, 13 Apr 2023 10:40:34 +0000 In-Reply-To: <20230413104034.1086717-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230413104034.1086717-1-yosryahmed@google.com> X-Mailer: git-send-email 2.40.0.577.gac1e443424-goog Message-ID: <20230413104034.1086717-4-yosryahmed@google.com> Subject: [PATCH v6 3/3] mm: vmscan: refactor updating current->reclaim_state From: Yosry Ahmed To: Andrew Morton , Alexander Viro , "Darrick J. Wong" , Christoph Lameter , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, "Matthew Wilcox (Oracle)" , Miaohe Lin , David Hildenbrand , Johannes Weiner , Peter Xu , NeilBrown , Shakeel Butt , Michal Hocko , Yu Zhao , Dave Chinner , Tim Chen Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yosry Ahmed Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org During reclaim, we keep track of pages reclaimed from other means than LRU-based reclaim through scan_control->reclaim_state->reclaimed_slab, which we stash a pointer to in current task_struct. However, we keep track of more than just reclaimed slab pages through this. We also use it for clean file pages dropped through pruned inodes, and xfs buffer pages freed. Rename reclaimed_slab to reclaimed, and add a helper function that wraps updating it through current, so that future changes to this logic are contained within include/linux/swap.h. Signed-off-by: Yosry Ahmed Acked-by: Michal Hocko --- fs/inode.c | 3 +-- fs/xfs/xfs_buf.c | 3 +-- include/linux/swap.h | 17 ++++++++++++++++- mm/slab.c | 3 +-- mm/slob.c | 6 ++---- mm/slub.c | 5 ++--- 6 files changed, 23 insertions(+), 14 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index 4558dc2f1355..e60fcc41faf1 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -864,8 +864,7 @@ static enum lru_status inode_lru_isolate(struct list_head *item, __count_vm_events(KSWAPD_INODESTEAL, reap); else __count_vm_events(PGINODESTEAL, reap); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += reap; + mm_account_reclaimed_pages(reap); } iput(inode); spin_lock(lru_lock); diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 54c774af6e1c..15d1e5a7c2d3 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -286,8 +286,7 @@ xfs_buf_free_pages( if (bp->b_pages[i]) __free_page(bp->b_pages[i]); } - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += bp->b_page_count; + mm_account_reclaimed_pages(bp->b_page_count); if (bp->b_pages != bp->b_page_array) kmem_free(bp->b_pages); diff --git a/include/linux/swap.h b/include/linux/swap.h index 209a425739a9..e131ac155fb9 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -153,13 +153,28 @@ union swap_header { * memory reclaim */ struct reclaim_state { - unsigned long reclaimed_slab; + /* pages reclaimed outside of LRU-based reclaim */ + unsigned long reclaimed; #ifdef CONFIG_LRU_GEN /* per-thread mm walk data */ struct lru_gen_mm_walk *mm_walk; #endif }; +/* + * mm_account_reclaimed_pages(): account reclaimed pages outside of LRU-based + * reclaim + * @pages: number of pages reclaimed + * + * If the current process is undergoing a reclaim operation, increment the + * number of reclaimed pages by @pages. + */ +static inline void mm_account_reclaimed_pages(unsigned long pages) +{ + if (current->reclaim_state) + current->reclaim_state->reclaimed += pages; +} + #ifdef __KERNEL__ struct address_space; diff --git a/mm/slab.c b/mm/slab.c index dabc2a671fc6..64bf1de817b2 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1392,8 +1392,7 @@ static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; + mm_account_reclaimed_pages(1 << order); unaccount_slab(slab, order, cachep); __free_pages(&folio->page, order); } diff --git a/mm/slob.c b/mm/slob.c index fe567fcfa3a3..79cc8680c973 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -61,7 +61,7 @@ #include #include -#include /* struct reclaim_state */ +#include /* mm_account_reclaimed_pages() */ #include #include #include @@ -211,9 +211,7 @@ static void slob_free_pages(void *b, int order) { struct page *sp = virt_to_page(b); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; - + mm_account_reclaimed_pages(1 << order); mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, -(PAGE_SIZE << order)); __free_pages(sp, order); diff --git a/mm/slub.c b/mm/slub.c index 39327e98fce3..7aa30eef8235 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -11,7 +11,7 @@ */ #include -#include /* struct reclaim_state */ +#include /* mm_account_reclaimed_pages() */ #include #include #include @@ -2063,8 +2063,7 @@ static void __free_slab(struct kmem_cache *s, struct slab *slab) /* Make the mapping reset visible before clearing the flag */ smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += pages; + mm_account_reclaimed_pages(pages); unaccount_slab(slab, order, s); __free_pages(&folio->page, order); }