From nobody Mon Feb 9 16:13:19 2026 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E904125B1 for ; Wed, 14 Feb 2024 06:06:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707890767; cv=none; b=RXVrPB1JXd4Vhfq1MUeE9vvBzLv31S5TNulplVaQCYgmOI5B3dJzctJSBrs40yUc8f9QfvtJ5svqCuTEew0MoZmE2Qa3z6lYYACSWPvLav5avHwCLE3CTDvicuJHcH3ZYJ9Ns/yjV3LTT86xBbxNRZT7yShp8i6a1Tkdx1aLoPw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707890767; c=relaxed/simple; bh=N9V0u3Ch6t/WSSGIrkB/hnLuxMA5NOlPuGRvTZgM1xU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=dG3SwRYVS5/zY9SUJmWQObwVoZdPOSRSN0/HvOFa1rHREfwmSbrv+gvEH72MCcImPFL0dvubAyexniwSnTozAgaRyOhKkcEqSKeiCmS+9F6fF1ykZLfjlUkaw4+2AqVOAsFdVIdtkvxrE1/q3b/SvdnWM9IYvWwC8+7QFG3ekn0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--kinseyho.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=wY1I/0ng; arc=none smtp.client-ip=209.85.210.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--kinseyho.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="wY1I/0ng" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-6e09015f811so5954067b3a.0 for ; Tue, 13 Feb 2024 22:06:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1707890765; x=1708495565; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=QH8wNJ7lAHDhvm3bFylVV17pyKkkH6HT7TXZodNBMaI=; b=wY1I/0ng2hVYWb4vthSvyheDQnCI1i6k0vFospCrhnotctDssViM/npp5seNlWu2NM 32ruKaifotutq2sO3dqijdU0/Gp4H40hRdnUFGRAYxV+XPYfnWUXivzJYRMKihc1LJa4 vUdiQCwi1e/HEB460zT+PIZfrmCT+tQynCS/H2Vlm/n/nu79MYB33TJyyH39edztJLBr eVAnKMwYMZo0SOhER6roD8n3oBTBStuz+cA3rIqFWK9MKV3oOHvBxEGFvmQfx4+6AqqC qJVZl/T/T8sJ5yHhmES4bCfaP1oBMFBZDyG6+yUU6RJbhXlSxPMIa8Uj8G0ttYpcIOI6 AxKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707890765; x=1708495565; 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=QH8wNJ7lAHDhvm3bFylVV17pyKkkH6HT7TXZodNBMaI=; b=p4MHeh/ufvsKh39QNwmyiBygjiWMqMt/UvlG1nQy3plxiKKqIEcSdyIRTUOCLYc0+8 nGpxIJu8BgXUPjHXvELzRHzw7olySwYyXqZ3OyeCPYWEzix6hvrG+GJ/74hSx8ZURmi/ KXBz9YNwYaYjoHFgD88nY6O4Dk+zeYq6TBEFbFofxc/uPBiRIYHL5pR/QfHazPtezIal LDSOwVf9IubtdmVN5VtpGvzrK3uN4J8Qn8vTZ1jPy481kEi4efVsQP8My8FfYBh1pyiX iSFl2JT+oSq9/8mR060/W5coo3SBBOvCM/wVG4AipZnkvRhaV8VcHXeh8l/xTEZK+s0C 6MWA== X-Forwarded-Encrypted: i=1; AJvYcCWv7MGMS1QbXcN0o2ps+iD4cKQnIcvyu29T0gSC47Ca2BA66CIXxdDhEo0p9kcdmO4g0xLLdf4rV4/SJVMNeieg9oCHU0ewEQsNnMAF X-Gm-Message-State: AOJu0YwhBLPy2C1irbldv4nF0ZXIh6rSZBo9tgYn2hid8xioJKus/WzS RPP9/SzYjzCGXz6yw0Cwu9lGoBSblHa1BuUs0a6I4B1/IOPNU0EAS15xxMbu90Drl/ljpR4mUm6 w/Czv11bEeg== X-Google-Smtp-Source: AGHT+IHQunAmjkzKIPCb68OjVMfuFVv2mPMH+2t6Wiy6R/pOgsm2Z2RPiWQL7A62g5M5NjpLQpMX+lR14ejk/A== X-Received: from kinseyct.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:46b]) (user=kinseyho job=sendgmr) by 2002:a05:6a00:2d9e:b0:6e0:a9bc:ef63 with SMTP id fb30-20020a056a002d9e00b006e0a9bcef63mr112938pfb.0.1707890764929; Tue, 13 Feb 2024 22:06:04 -0800 (PST) Date: Wed, 14 Feb 2024 06:05:37 +0000 In-Reply-To: <20240214060538.3524462-1-kinseyho@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240214060538.3524462-1-kinseyho@google.com> X-Mailer: git-send-email 2.43.0.687.g38aa6559b0-goog Message-ID: <20240214060538.3524462-5-kinseyho@google.com> Subject: [PATCH mm-unstable v1 4/5] mm/mglru: improve struct lru_gen_mm_walk From: Kinsey Ho To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Yu Zhao , Donet Tom , "Aneesh Kumar K . V" , Kinsey Ho Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Rename max_seq to seq in struct lru_gen_mm_walk to keep consistent with struct lru_gen_mm_state. Note that seq is not always up to date with max_seq from lru_gen_folio. No functional changes. Signed-off-by: Kinsey Ho --- include/linux/mmzone.h | 6 ++--- mm/vmscan.c | 50 ++++++++++++++++++++++-------------------- 2 files changed, 29 insertions(+), 27 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 22fd46c77840..e51c75270e82 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -468,7 +468,7 @@ enum { #define NR_BLOOM_FILTERS 2 =20 struct lru_gen_mm_state { - /* set to max_seq after each iteration */ + /* synced with max_seq after each iteration */ unsigned long seq; /* where the current iteration continues after */ struct list_head *head; @@ -483,8 +483,8 @@ struct lru_gen_mm_state { struct lru_gen_mm_walk { /* the lruvec under reclaim */ struct lruvec *lruvec; - /* unstable max_seq from lru_gen_folio */ - unsigned long max_seq; + /* max_seq from lru_gen_folio: can be out of date */ + unsigned long seq; /* the next address within an mm to scan */ unsigned long next_addr; /* to batch promoted pages */ diff --git a/mm/vmscan.c b/mm/vmscan.c index 8c77c332a67a..f1019afa7813 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2906,7 +2906,7 @@ static void reset_mm_stats(struct lru_gen_mm_walk *wa= lk, bool last) =20 lockdep_assert_held(&get_mm_list(lruvec_memcg(lruvec))->lock); =20 - hist =3D lru_hist_from_seq(walk->max_seq); + hist =3D lru_hist_from_seq(walk->seq); =20 for (i =3D 0; i < NR_MM_STATS; i++) { WRITE_ONCE(mm_state->stats[hist][i], @@ -2915,7 +2915,7 @@ static void reset_mm_stats(struct lru_gen_mm_walk *wa= lk, bool last) } =20 if (NR_HIST_GENS > 1 && last) { - hist =3D lru_hist_from_seq(walk->max_seq + 1); + hist =3D lru_hist_from_seq(walk->seq + 1); =20 for (i =3D 0; i < NR_MM_STATS; i++) WRITE_ONCE(mm_state->stats[hist][i], 0); @@ -2944,9 +2944,9 @@ static bool iterate_mm_list(struct lru_gen_mm_walk *w= alk, struct mm_struct **ite */ spin_lock(&mm_list->lock); =20 - VM_WARN_ON_ONCE(mm_state->seq + 1 < walk->max_seq); + VM_WARN_ON_ONCE(mm_state->seq + 1 < walk->seq); =20 - if (walk->max_seq <=3D mm_state->seq) + if (walk->seq <=3D mm_state->seq) goto done; =20 if (!mm_state->head) @@ -2976,7 +2976,7 @@ static bool iterate_mm_list(struct lru_gen_mm_walk *w= alk, struct mm_struct **ite spin_unlock(&mm_list->lock); =20 if (mm && first) - reset_bloom_filter(mm_state, walk->max_seq + 1); + reset_bloom_filter(mm_state, walk->seq + 1); =20 if (*iter) mmput_async(*iter); @@ -2986,7 +2986,7 @@ static bool iterate_mm_list(struct lru_gen_mm_walk *w= alk, struct mm_struct **ite return last; } =20 -static bool iterate_mm_list_nowalk(struct lruvec *lruvec, unsigned long ma= x_seq) +static bool iterate_mm_list_nowalk(struct lruvec *lruvec, unsigned long se= q) { bool success =3D false; struct mem_cgroup *memcg =3D lruvec_memcg(lruvec); @@ -2995,9 +2995,9 @@ static bool iterate_mm_list_nowalk(struct lruvec *lru= vec, unsigned long max_seq) =20 spin_lock(&mm_list->lock); =20 - VM_WARN_ON_ONCE(mm_state->seq + 1 < max_seq); + VM_WARN_ON_ONCE(mm_state->seq + 1 < seq); =20 - if (max_seq > mm_state->seq) { + if (seq > mm_state->seq) { mm_state->head =3D NULL; mm_state->tail =3D NULL; WRITE_ONCE(mm_state->seq, mm_state->seq + 1); @@ -3348,7 +3348,8 @@ static bool walk_pte_range(pmd_t *pmd, unsigned long = start, unsigned long end, struct lru_gen_mm_walk *walk =3D args->private; struct mem_cgroup *memcg =3D lruvec_memcg(walk->lruvec); struct pglist_data *pgdat =3D lruvec_pgdat(walk->lruvec); - int old_gen, new_gen =3D lru_gen_from_seq(walk->max_seq); + DEFINE_MAX_SEQ(walk->lruvec); + int old_gen, new_gen =3D lru_gen_from_seq(max_seq); =20 pte =3D pte_offset_map_nolock(args->mm, pmd, start & PMD_MASK, &ptl); if (!pte) @@ -3415,7 +3416,8 @@ static void walk_pmd_range_locked(pud_t *pud, unsigne= d long addr, struct vm_area struct lru_gen_mm_walk *walk =3D args->private; struct mem_cgroup *memcg =3D lruvec_memcg(walk->lruvec); struct pglist_data *pgdat =3D lruvec_pgdat(walk->lruvec); - int old_gen, new_gen =3D lru_gen_from_seq(walk->max_seq); + DEFINE_MAX_SEQ(walk->lruvec); + int old_gen, new_gen =3D lru_gen_from_seq(max_seq); =20 VM_WARN_ON_ONCE(pud_leaf(*pud)); =20 @@ -3546,7 +3548,7 @@ static void walk_pmd_range(pud_t *pud, unsigned long = start, unsigned long end, walk_pmd_range_locked(pud, addr, vma, args, bitmap, &first); } =20 - if (!walk->force_scan && !test_bloom_filter(mm_state, walk->max_seq, pmd= + i)) + if (!walk->force_scan && !test_bloom_filter(mm_state, walk->seq, pmd + i= )) continue; =20 walk->mm_stats[MM_NONLEAF_FOUND]++; @@ -3557,7 +3559,7 @@ static void walk_pmd_range(pud_t *pud, unsigned long = start, unsigned long end, walk->mm_stats[MM_NONLEAF_ADDED]++; =20 /* carry over to the next generation */ - update_bloom_filter(mm_state, walk->max_seq + 1, pmd + i); + update_bloom_filter(mm_state, walk->seq + 1, pmd + i); } =20 walk_pmd_range_locked(pud, -1, vma, args, bitmap, &first); @@ -3628,7 +3630,7 @@ static void walk_mm(struct mm_struct *mm, struct lru_= gen_mm_walk *walk) err =3D -EBUSY; =20 /* another thread might have called inc_max_seq() */ - if (walk->max_seq !=3D max_seq) + if (walk->seq !=3D max_seq) break; =20 /* folio_update_gen() requires stable folio_memcg() */ @@ -3765,7 +3767,7 @@ static bool try_to_inc_min_seq(struct lruvec *lruvec,= bool can_swap) return success; } =20 -static bool inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, +static bool inc_max_seq(struct lruvec *lruvec, unsigned long seq, bool can_swap, bool force_scan) { bool success; @@ -3773,14 +3775,14 @@ static bool inc_max_seq(struct lruvec *lruvec, unsi= gned long max_seq, int type, zone; struct lru_gen_folio *lrugen =3D &lruvec->lrugen; restart: - if (max_seq < READ_ONCE(lrugen->max_seq)) + if (seq < READ_ONCE(lrugen->max_seq)) return false; =20 spin_lock_irq(&lruvec->lru_lock); =20 VM_WARN_ON_ONCE(!seq_is_valid(lruvec)); =20 - success =3D max_seq =3D=3D lrugen->max_seq; + success =3D seq =3D=3D lrugen->max_seq; if (!success) goto unlock; =20 @@ -3833,7 +3835,7 @@ static bool inc_max_seq(struct lruvec *lruvec, unsign= ed long max_seq, return success; } =20 -static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_se= q, +static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long seq, bool can_swap, bool force_scan) { bool success; @@ -3842,13 +3844,13 @@ static bool try_to_inc_max_seq(struct lruvec *lruve= c, unsigned long max_seq, struct lru_gen_folio *lrugen =3D &lruvec->lrugen; struct lru_gen_mm_state *mm_state =3D get_mm_state(lruvec); =20 - VM_WARN_ON_ONCE(max_seq > READ_ONCE(lrugen->max_seq)); + VM_WARN_ON_ONCE(seq > READ_ONCE(lrugen->max_seq)); =20 if (!mm_state) - return inc_max_seq(lruvec, max_seq, can_swap, force_scan); + return inc_max_seq(lruvec, seq, can_swap, force_scan); =20 /* see the comment in iterate_mm_list() */ - if (max_seq <=3D READ_ONCE(mm_state->seq)) + if (seq <=3D READ_ONCE(mm_state->seq)) return false; =20 /* @@ -3858,18 +3860,18 @@ static bool try_to_inc_max_seq(struct lruvec *lruve= c, unsigned long max_seq, * is less efficient, but it avoids bursty page faults. */ if (!should_walk_mmu()) { - success =3D iterate_mm_list_nowalk(lruvec, max_seq); + success =3D iterate_mm_list_nowalk(lruvec, seq); goto done; } =20 walk =3D set_mm_walk(NULL, true); if (!walk) { - success =3D iterate_mm_list_nowalk(lruvec, max_seq); + success =3D iterate_mm_list_nowalk(lruvec, seq); goto done; } =20 walk->lruvec =3D lruvec; - walk->max_seq =3D max_seq; + walk->seq =3D seq; walk->can_swap =3D can_swap; walk->force_scan =3D force_scan; =20 @@ -3880,7 +3882,7 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec,= unsigned long max_seq, } while (mm); done: if (success) { - success =3D inc_max_seq(lruvec, max_seq, can_swap, force_scan); + success =3D inc_max_seq(lruvec, seq, can_swap, force_scan); WARN_ON_ONCE(!success); } =20 --=20 2.43.0.687.g38aa6559b0-goog