From nobody Tue Feb 10 21:38:26 2026 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 6AD3DC77B60 for ; Tue, 28 Mar 2023 22:17:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229456AbjC1WRj (ORCPT ); Tue, 28 Mar 2023 18:17:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230168AbjC1WRQ (ORCPT ); Tue, 28 Mar 2023 18:17:16 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE7DA30D8 for ; Tue, 28 Mar 2023 15:17:03 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id j15-20020a17090a318f00b0023fe33f8825so3792021pjb.9 for ; Tue, 28 Mar 2023 15:17:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1680041823; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=a7F6fk9fZnPdw9ddOVIzAjBdiTpqd88vdaggqxhF/qs=; b=j2h7VlEdeGIL4dqtCRH6krZRXCzlm8zdD/VKFrhl2Ix5hroKwD9u6hjC+9l9HOi6UV H1JPSNu1LdgWvdxHE9hg+SM93x1Jht2L9pd8vgLQEuBZlRpZngZUgkiaZwaZa4gCkUC+ zgspBsM6/B8TFiwy4IbbIfRW24OLGYSFku2vitXovcEwbuAN1td3zyOf9AyMfligZ5Lp BhTKdBAPhJ+a7QI4Cj7LZxYyn4A2yXYMpirZryPEzjspDaCYUkIzUrMU1Kd6ErRoShgT XFMZOBTc6edK5ZIe1IhscJC8wUQ57Xb89+9zAOCcDb3JVfb8T7SfV7MPXlrp4JguLYCz aCRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680041823; 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=a7F6fk9fZnPdw9ddOVIzAjBdiTpqd88vdaggqxhF/qs=; b=FtwAu1R7pkb08GbTKddt8h7tHUe3NBnQ/er6RABH/I1cAz7OHjQOquplGpEND2KUgr sGkW/kE6WM5RtgIBr5BzUQcF2VOyd0AQrTp/3MsoOSntHZF1l3YcPheSfoJeUveTB+lO V4Oba7NbEYO7Sqn9lmmkcpIconrKL77I0bMeCQM6a9kAWIs1WqbBmlIReoDElWFdEgEA dNUXXis3jMEINCqtv+E5kztAbfWwObmzFbZWZGmBDTToggzuIYbtGuXxjTVLEArmvXzC 9PFAIMjnz1Vomv0UAVhlXfxYnBrgwYLWGYJWgp5hJQ76co5B54dx2ojNKZ/vdBRdZXZs gwtA== X-Gm-Message-State: AAQBX9dMpUI0Ckj9rY6i4Q1vlstaTBzHUxb5s6UNBOb4ndmQAyP5VyeB rQWf2WW006AHU1hXgIfecYiFmialbQixriAm X-Google-Smtp-Source: AKy350YX9lhtezGewKcmJEZ6+PWl0qdkFOVRrH2qPmewBQAi0Jj2O6028tHTh6zpbuIXp3Yq/V52VHvowCQfk3sU X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a17:902:ec90:b0:1a0:763d:6c2a with SMTP id x16-20020a170902ec9000b001a0763d6c2amr6633613plg.10.1680041823533; Tue, 28 Mar 2023 15:17:03 -0700 (PDT) Date: Tue, 28 Mar 2023 22:16:42 +0000 In-Reply-To: <20230328221644.803272-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230328221644.803272-1-yosryahmed@google.com> X-Mailer: git-send-email 2.40.0.348.gf938b09366-goog Message-ID: <20230328221644.803272-8-yosryahmed@google.com> Subject: [PATCH v2 7/9] workingset: memcg: sleep when flushing stats in workingset_refault() From: Yosry Ahmed To: Tejun Heo , Josef Bacik , Jens Axboe , Zefan Li , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , "=?UTF-8?q?Michal=20Koutn=C3=BD?=" Cc: Vasily Averin , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, Yosry Ahmed Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" In workingset_refault(), we call mem_cgroup_flush_stats_atomic_ratelimited() to flush stats within an RCU read section and with sleeping disallowed. Move the call above the RCU read section and allow sleeping to avoid unnecessarily performing a lot of work without sleeping. Since workingset_refault() is the only caller of mem_cgroup_flush_stats_atomic_ratelimited(), just make it non-atomic, and rename it to mem_cgroup_flush_stats_ratelimited(). Signed-off-by: Yosry Ahmed Acked-by: Shakeel Butt Acked-by: Johannes Weiner Acked-by: Michal Hocko --- include/linux/memcontrol.h | 4 ++-- mm/memcontrol.c | 4 ++-- mm/workingset.c | 5 +++-- 3 files changed, 7 insertions(+), 6 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index b424ba3ebd09..a4bc3910a2eb 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1038,7 +1038,7 @@ static inline unsigned long lruvec_page_state_local(s= truct lruvec *lruvec, =20 void mem_cgroup_flush_stats(void); void mem_cgroup_flush_stats_atomic(void); -void mem_cgroup_flush_stats_atomic_ratelimited(void); +void mem_cgroup_flush_stats_ratelimited(void); =20 void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item i= dx, int val); @@ -1540,7 +1540,7 @@ static inline void mem_cgroup_flush_stats_atomic(void) { } =20 -static inline void mem_cgroup_flush_stats_atomic_ratelimited(void) +static inline void mem_cgroup_flush_stats_ratelimited(void) { } =20 diff --git a/mm/memcontrol.c b/mm/memcontrol.c index a2ce3aa10d94..361c0bbf7283 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -673,10 +673,10 @@ void mem_cgroup_flush_stats_atomic(void) do_flush_stats(true); } =20 -void mem_cgroup_flush_stats_atomic_ratelimited(void) +void mem_cgroup_flush_stats_ratelimited(void) { if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) - mem_cgroup_flush_stats_atomic(); + mem_cgroup_flush_stats(); } =20 static void flush_memcg_stats_dwork(struct work_struct *w) diff --git a/mm/workingset.c b/mm/workingset.c index dab0c362b9e3..3025beee9b34 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -406,6 +406,9 @@ void workingset_refault(struct folio *folio, void *shad= ow) unpack_shadow(shadow, &memcgid, &pgdat, &eviction, &workingset); eviction <<=3D bucket_order; =20 + /* Flush stats (and potentially sleep) before holding RCU read lock */ + mem_cgroup_flush_stats_ratelimited(); + rcu_read_lock(); /* * Look up the memcg associated with the stored ID. It might @@ -461,8 +464,6 @@ void workingset_refault(struct folio *folio, void *shad= ow) lruvec =3D mem_cgroup_lruvec(memcg, pgdat); =20 mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr); - - mem_cgroup_flush_stats_atomic_ratelimited(); /* * Compare the distance to the existing workingset size. We * don't activate pages that couldn't stay resident even if --=20 2.40.0.348.gf938b09366-goog