From patchwork Wed Nov 27 02:57:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yuanchu Xie X-Patchwork-Id: 13886499 Received: from mail-oa1-f73.google.com (mail-oa1-f73.google.com [209.85.160.73]) (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 B523113A888 for ; Wed, 27 Nov 2024 02:57:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732676271; cv=none; b=r+E5ycNXYKJZX+LOp3dZxxl3S7kbhxFh3OEwys81msTkUJqKMgwKx9jWShWlRkh1/4SlaEtvXvXYQaneePFXbWCpOlyjeydGM8oeeubYAAuv3mBYlWXaw5EbFHNYqW3NVW7eiL1e6CoPn2X0QKnAvnm6cKf6KD0WAFtqIAKEm48= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732676271; c=relaxed/simple; bh=WTcNbuwg+h1080/4gOPGJLMDusJrVSUsnxgGAyu/+1o=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=VnnfAwh2hdysrbLN4232XFstSHiT6Bbb72+6ESmz8VO/aMkxnlbiRvdIyTZERwz4Nv3XmNwpDLBk9pZuEODiCpTWW5mJu0AC/OzY0Nxk2eLkf9Qlsu1XFDx/6AC7IClyoHE625W/hTFN7zb/mSDiGadjohSxZG654tM06YMxqn0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--yuanchu.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ZEPWqO4R; arc=none smtp.client-ip=209.85.160.73 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--yuanchu.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ZEPWqO4R" Received: by mail-oa1-f73.google.com with SMTP id 586e51a60fabf-2962c45ba90so5150329fac.0 for ; Tue, 26 Nov 2024 18:57:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1732676268; x=1733281068; 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=jJsIXJ522dse8Oa1czRmZ0i3siB+gYc3GobTJqrZlLM=; b=ZEPWqO4RFiM4Siq8DtlQ30RZGjaTvJms0NJYyGmhnO5CGL0JK7gaXbeL9SMtFb3XZI yd4T/4Hbd7XeuW4+9ue88/rTEbeCm0JHyHIU8/Q2+XrhhDgguDXrYvnu8WIvTssaEtSj wHNCBdSHj3w4mZipDZUzpjwThs1sodFtY2clPewXCShAlGznqL0PfPUR5nwkztw7f6rH PT/Lb36D4PNO2PBuFjDLbEUCusdET7GB2nY2lVk0jdN5xUdsCcxs+o6heGrQhkYnuoHV bCct8s2oQ/ndzcewBDatA8cJpGRyzWoyE9yAOOrmyBVniEliU1VwF9FJcSqg5Ed5vdYL hrEQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1732676268; x=1733281068; 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=jJsIXJ522dse8Oa1czRmZ0i3siB+gYc3GobTJqrZlLM=; b=gKC1HfbTGW1xCZNXGtwVKHvoWK+dXtQvMF/SOvlUeIL2uNoYqya8ImsKCWVF4gMWVJ H7jPaByHUtubCsI2ot0bz6ty1agmIdH7xHE+tWVFGkB9OZIx6HjJeNh78hWiEzvuafrJ 3jpOJvRub1WAveIGwtbN2dW5h4dXhLnegpp6bLSjbGZ2oa/w8W1KTYZx2Y6Fb0CThOQB aIpIjySlPzw4qyGev/c7aavcqGqTQxkHUnK/gBUGtn/EdQggiG86GxTlUWHaGayAThsa TCATDXKWfAGVGadArJbtsjCl+AboiuAQF4Nk5i2brpejjLgFXNPpRzFs5O/0PJoiqkA6 EDKg== X-Forwarded-Encrypted: i=1; AJvYcCVM/zSJ1YP+Zvy2pLNMkL+eTY9Ch+2idng289+x3adpFQYbfn8rXv8CFxvY1gMrkC+frncjUJshXI89+PMnJaM=@vger.kernel.org X-Gm-Message-State: AOJu0Yx3nFJmxdix9eFGalxJsCFn+mOTe2v+o1FpqL6KYJmAltbGVKm0 H9UBgtgRScQd9qPVH5Q3Ez3oxtLRalTIEBqN8dB2n+XSNcOwMgTBlsLPWD2ls+N49h1epmPzVi+ kdEnaJw== X-Google-Smtp-Source: AGHT+IHpxh9NC9fR/Y+VVMw56gHiKhQb3M845RK+LO+TsitSupQfuVS+RxLJBMoZkNtQHfRh61ZaI/968chM X-Received: from oabxa1.prod.google.com ([2002:a05:6870:7f01:b0:295:f4c4:2bdd]) (user=yuanchu job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6870:9a98:b0:297:27c6:d50f with SMTP id 586e51a60fabf-29dc3f9ee1emr1306226fac.2.1732676268691; Tue, 26 Nov 2024 18:57:48 -0800 (PST) Date: Tue, 26 Nov 2024 18:57:22 -0800 In-Reply-To: <20241127025728.3689245-1-yuanchu@google.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241127025728.3689245-1-yuanchu@google.com> X-Mailer: git-send-email 2.47.0.338.g60cca15819-goog Message-ID: <20241127025728.3689245-4-yuanchu@google.com> Subject: [PATCH v4 3/9] mm: report workingset during memory pressure driven scanning From: Yuanchu Xie To: Andrew Morton , David Hildenbrand , "Aneesh Kumar K.V" , Khalid Aziz , Henry Huang , Yu Zhao , Dan Williams , Gregory Price , Huang Ying , Lance Yang , Randy Dunlap , Muhammad Usama Anjum Cc: Tejun Heo , Johannes Weiner , " =?utf-8?q?Michal_Koutn=C3=BD?= " , Jonathan Corbet , Greg Kroah-Hartman , "Rafael J. Wysocki" , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , " =?utf-8?q?Eugenio_P=C3=A9rez?= " , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Mike Rapoport , Shuah Khan , Christian Brauner , Daniel Watson , Yuanchu Xie , cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux.dev, linux-mm@kvack.org, linux-kselftest@vger.kernel.org When a node reaches its low watermarks and wakes up kswapd, notify all userspace programs waiting on the workingset page age histogram of the memory pressure, so a userspace agent can read the workingset report in time and make policy decisions, such as logging, oom-killing, or migration. Sysfs interface: /sys/devices/system/node/nodeX/workingset_report/report_threshold time in milliseconds that specifies how often the userspace agent can be notified for node memory pressure. Signed-off-by: Yuanchu Xie --- include/linux/workingset_report.h | 4 +++ mm/internal.h | 12 ++++++++ mm/vmscan.c | 46 +++++++++++++++++++++++++++++++ mm/workingset_report.c | 43 ++++++++++++++++++++++++++++- 4 files changed, 104 insertions(+), 1 deletion(-) diff --git a/include/linux/workingset_report.h b/include/linux/workingset_report.h index 8bae6a600410..2ec8b927b200 100644 --- a/include/linux/workingset_report.h +++ b/include/linux/workingset_report.h @@ -37,7 +37,11 @@ struct wsr_page_age_histo { }; struct wsr_state { + unsigned long report_threshold; unsigned long refresh_interval; + + struct kernfs_node *page_age_sys_file; + /* breakdown of workingset by page age */ struct mutex page_age_lock; struct wsr_page_age_histo *page_age; diff --git a/mm/internal.h b/mm/internal.h index bbd3c1501bac..508b7d9937d6 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -479,6 +479,18 @@ bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long seq, bool can_swap, bool force_scan); void set_task_reclaim_state(struct task_struct *task, struct reclaim_state *rs); +#ifdef CONFIG_WORKINGSET_REPORT +/* + * in mm/wsr.c + */ +void notify_workingset(struct mem_cgroup *memcg, struct pglist_data *pgdat); +#else +static inline void notify_workingset(struct mem_cgroup *memcg, + struct pglist_data *pgdat) +{ +} +#endif + /* * in mm/rmap.c: */ diff --git a/mm/vmscan.c b/mm/vmscan.c index 89da4d8dfb5f..2bca81271d15 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2578,6 +2578,15 @@ static bool can_age_anon_pages(struct pglist_data *pgdat, return can_demote(pgdat->node_id, sc); } +#ifdef CONFIG_WORKINGSET_REPORT +static void try_to_report_workingset(struct pglist_data *pgdat, struct scan_control *sc); +#else +static inline void try_to_report_workingset(struct pglist_data *pgdat, + struct scan_control *sc) +{ +} +#endif + #ifdef CONFIG_LRU_GEN #ifdef CONFIG_LRU_GEN_ENABLED @@ -4004,6 +4013,8 @@ static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) set_initial_priority(pgdat, sc); + try_to_report_workingset(pgdat, sc); + memcg = mem_cgroup_iter(NULL, NULL, NULL); do { struct lruvec *lruvec = mem_cgroup_lruvec(memcg, pgdat); @@ -5649,6 +5660,38 @@ static int __init init_lru_gen(void) }; late_initcall(init_lru_gen); +#ifdef CONFIG_WORKINGSET_REPORT +static void try_to_report_workingset(struct pglist_data *pgdat, + struct scan_control *sc) +{ + struct mem_cgroup *memcg = sc->target_mem_cgroup; + struct wsr_state *wsr = &mem_cgroup_lruvec(memcg, pgdat)->wsr; + unsigned long threshold = READ_ONCE(wsr->report_threshold); + + if (sc->priority == DEF_PRIORITY) + return; + + if (!threshold) + return; + + if (!mutex_trylock(&wsr->page_age_lock)) + return; + + if (!wsr->page_age) { + mutex_unlock(&wsr->page_age_lock); + return; + } + + if (time_is_after_jiffies(wsr->page_age->timestamp + threshold)) { + mutex_unlock(&wsr->page_age_lock); + return; + } + + mutex_unlock(&wsr->page_age_lock); + notify_workingset(memcg, pgdat); +} +#endif /* CONFIG_WORKINGSET_REPORT */ + #else /* !CONFIG_LRU_GEN */ static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) @@ -6200,6 +6243,9 @@ static void shrink_zones(struct zonelist *zonelist, struct scan_control *sc) if (zone->zone_pgdat == last_pgdat) continue; last_pgdat = zone->zone_pgdat; + + if (!sc->proactive) + try_to_report_workingset(zone->zone_pgdat, sc); shrink_node(zone->zone_pgdat, sc); } diff --git a/mm/workingset_report.c b/mm/workingset_report.c index 8678536ccfc7..bbefb0046669 100644 --- a/mm/workingset_report.c +++ b/mm/workingset_report.c @@ -320,6 +320,33 @@ static struct wsr_state *kobj_to_wsr(struct kobject *kobj) return &mem_cgroup_lruvec(NULL, kobj_to_pgdat(kobj))->wsr; } +static ssize_t report_threshold_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct wsr_state *wsr = kobj_to_wsr(kobj); + unsigned int threshold = READ_ONCE(wsr->report_threshold); + + return sysfs_emit(buf, "%u\n", jiffies_to_msecs(threshold)); +} + +static ssize_t report_threshold_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t len) +{ + unsigned int threshold; + struct wsr_state *wsr = kobj_to_wsr(kobj); + + if (kstrtouint(buf, 0, &threshold)) + return -EINVAL; + + WRITE_ONCE(wsr->report_threshold, msecs_to_jiffies(threshold)); + + return len; +} + +static struct kobj_attribute report_threshold_attr = + __ATTR_RW(report_threshold); + static ssize_t refresh_interval_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { @@ -474,6 +501,7 @@ static ssize_t page_age_show(struct kobject *kobj, struct kobj_attribute *attr, static struct kobj_attribute page_age_attr = __ATTR_RO(page_age); static struct attribute *workingset_report_attrs[] = { + &report_threshold_attr.attr, &refresh_interval_attr.attr, &page_age_intervals_attr.attr, &page_age_attr.attr, @@ -495,8 +523,13 @@ void wsr_init_sysfs(struct node *node) wsr = kobj_to_wsr(kobj); - if (sysfs_create_group(kobj, &workingset_report_attr_group)) + if (sysfs_create_group(kobj, &workingset_report_attr_group)) { pr_warn("Workingset report failed to create sysfs files\n"); + return; + } + + wsr->page_age_sys_file = + kernfs_walk_and_get(kobj->sd, "workingset_report/page_age"); } EXPORT_SYMBOL_GPL(wsr_init_sysfs); @@ -509,6 +542,14 @@ void wsr_remove_sysfs(struct node *node) return; wsr = kobj_to_wsr(kobj); + kernfs_put(wsr->page_age_sys_file); sysfs_remove_group(kobj, &workingset_report_attr_group); } EXPORT_SYMBOL_GPL(wsr_remove_sysfs); + +void notify_workingset(struct mem_cgroup *memcg, struct pglist_data *pgdat) +{ + struct wsr_state *wsr = &mem_cgroup_lruvec(memcg, pgdat)->wsr; + + kernfs_notify(wsr->page_age_sys_file); +}