From patchwork Wed Mar 27 21:31:03 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yuanchu Xie X-Patchwork-Id: 13607480 Received: from mail-yw1-f202.google.com (mail-yw1-f202.google.com [209.85.128.202]) (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 D1FE3153BCC for ; Wed, 27 Mar 2024 21:31:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711575098; cv=none; b=JC1jkxEtiqvbieGHZUaBWIOAutd2tKi579SfLSmychIiGHAbDYqLK14DwHKU065FddcxhfZ5kx65SJZo/C2QDYDxEUVoHPtORRCqyI5lCmnXiI5J5s5BvI2WZ1XQq8c1TzuYwPxBZ6iT0OsAlTdEFEHDlyyrSS6/em8II64ZEB8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711575098; c=relaxed/simple; bh=YVxkh2DGqIrC+tRI7u6jcPwoHLc5KJBc+Hr3yy4569I=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=gJmuTulv1L6ZEq1wd+LGpmvRXxa0w8TXpBeMv6TRQtbJegaBwtgSYG6iAr8PldUIEpaMxXzMbbVGNDKgsZUyjeh5g/f4xJY2S82SyGTzI/hdJJLUiVFdeGl6MxdQmEbD7qgXXeCOMU3L4NKr7ngOhvII7yr6/4Rvt6ndgO6ZM1s= 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=WD1KDZmJ; arc=none smtp.client-ip=209.85.128.202 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="WD1KDZmJ" Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-60a55cd262aso5130377b3.2 for ; Wed, 27 Mar 2024 14:31:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1711575096; x=1712179896; 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=LB+v0i5rcgoLcT2egvPDfe+7I6p18e+cGMfRHtt3nUw=; b=WD1KDZmJFIJtqMBnYSm7A5H60Wc92/GFSsGyehydFXl4VUmvpZmn380dwIuLNsoNKv Ou+rxoeXHXa9cNR/Pa293XuIOrrLUD5DwSL3BZO9XcL4sDc/D+63nBAwhkw4p1XskKJs IkoMemLzfvkPgter0LPhiJbEtu9D6GNcKMJnAyhFACnebFS8ZCOmxBwEyOpoRkg6TfGT tE7/e9xg7PdueqH58kbezuuokO5yBTttpqTQFvJ6EOm45beGelCm4gsFbCLQytTKGMXA J2UThlH33d9tZK8cd5Bu1xHG+HkvZAOUztzYkjAjg3TWiW9OSdDIB9gyA8nDvgHnwiCX PY4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711575096; x=1712179896; 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=LB+v0i5rcgoLcT2egvPDfe+7I6p18e+cGMfRHtt3nUw=; b=YMcto0aMpEf7g+hjMmkUfImG59Etl8fEN6ehOf7lTwpaXgYWqkO2iqrHKChe0eaWSk hsDYRkeGxRiLZ9Z2tCl336pWteKrOeNjQXeFb3XismUekJreQ18c+8LApwrgciw9HPI5 UMzvQq+g/08SG2C+Te2OvaQskiZ4EVGbFPtrZQtqA8mJ6oSDhx1mtDarchebV1ISKbye /5aQfM7rpQo543ub0qoaoaiJx0nJsEPek5O1sPvv3Eijds37VHq2W0brPxvRyyyCTuRE NABRWSdYzp6cx2uQUrrk0Xo+K+noE1pQvZh/uFG0ZqlJwXSHTaY2Om8r1St0eFT78GUd YlMw== X-Forwarded-Encrypted: i=1; AJvYcCWuG4v55q7Qvyo3jAcb6WbfXRIYMBv6a3qPSMvueGjUkcQpW8EopDayUWD8paHqn8kAmxiX1AgDO7pricJjIgLtgQy8KniC0MK5ykhY7MUn X-Gm-Message-State: AOJu0YwZw5W6BUT9Tpsso4k9RtoDXEg6vCIDo7eEO9lPKE4TyLBZ5WiB NjAdZ5tM67wXxtwWAot6/B3QHEcS0BhpUaGYQyuTpLwRqBIF/pqe/b4d79qpHAYSdw8H7hRJqfe N5/NO5A== X-Google-Smtp-Source: AGHT+IHMceXyiMQRNVP1E9sG9l7GvMJZx9fuMZnRf4fjgo+ewu4QirMYVr1TGSmtvsHYoxnOh9k/JVnZeT/d X-Received: from yuanchu-desktop.svl.corp.google.com ([2620:15c:2a3:200:6df3:ef42:a58e:a6b1]) (user=yuanchu job=sendgmr) by 2002:a05:6902:2183:b0:dc6:53c3:bcbd with SMTP id dl3-20020a056902218300b00dc653c3bcbdmr314870ybb.7.1711575095837; Wed, 27 Mar 2024 14:31:35 -0700 (PDT) Date: Wed, 27 Mar 2024 14:31:03 -0700 In-Reply-To: <20240327213108.2384666-1-yuanchu@google.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240327213108.2384666-1-yuanchu@google.com> X-Mailer: git-send-email 2.44.0.396.g6e790dbe36-goog Message-ID: <20240327213108.2384666-5-yuanchu@google.com> Subject: [RFC PATCH v3 4/8] mm: report workingset during memory pressure driven scanning From: Yuanchu Xie To: David Hildenbrand , "Aneesh Kumar K.V" , Khalid Aziz , Henry Huang , Yu Zhao , Dan Williams , Gregory Price , Huang Ying Cc: Wei Xu , David Rientjes , Greg Kroah-Hartman , "Rafael J. Wysocki" , Andrew Morton , Johannes Weiner , Michal Hocko , Roman Gushchin , Muchun Song , Shuah Khan , Yosry Ahmed , Matthew Wilcox , Sudarshan Rajagopalan , Kairui Song , "Michael S. Tsirkin" , Vasily Averin , Nhat Pham , Miaohe Lin , Qi Zheng , Abel Wu , "Vishal Moola (Oracle)" , Kefeng Wang , Yuanchu Xie , linux-kernel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.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 | 6 +++++ mm/vmscan.c | 44 +++++++++++++++++++++++++++++++ mm/workingset_report.c | 39 +++++++++++++++++++++++++++ 4 files changed, 93 insertions(+) diff --git a/include/linux/workingset_report.h b/include/linux/workingset_report.h index 23d2ae747a31..589d240d6251 100644 --- a/include/linux/workingset_report.h +++ b/include/linux/workingset_report.h @@ -35,7 +35,11 @@ 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 151f09c6983e..36480c7ac0dd 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -209,8 +209,14 @@ extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason /* * in mm/wsr.c */ +void notify_workingset(struct mem_cgroup *memcg, struct pglist_data *pgdat); /* Requires wsr->page_age_lock held */ void wsr_refresh_scan(struct lruvec *lruvec, unsigned long refresh_interval); +#else +static inline void notify_workingset(struct mem_cgroup *memcg, + struct pglist_data *pgdat) +{ +} #endif /* diff --git a/mm/vmscan.c b/mm/vmscan.c index 5f04a04f5261..c6acd5265b3f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2535,6 +2535,15 @@ 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 @@ -3936,6 +3945,8 @@ static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) if (!min_ttl || sc->order || sc->priority == DEF_PRIORITY) return; + try_to_report_workingset(pgdat, sc); + memcg = mem_cgroup_iter(NULL, NULL, NULL); do { struct lruvec *lruvec = mem_cgroup_lruvec(memcg, pgdat); @@ -5650,6 +5661,36 @@ void wsr_refresh_scan(struct lruvec *lruvec, unsigned long refresh_interval) } } } + +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 */ @@ -6177,6 +6218,9 @@ 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 370e7d355604..3ed3b0e8f8ad 100644 --- a/mm/workingset_report.c +++ b/mm/workingset_report.c @@ -269,6 +269,33 @@ 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) { @@ -412,6 +439,7 @@ 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, @@ -437,6 +465,9 @@ void wsr_register_node(struct node *node) pr_warn("WSR failed to created group"); return; } + + wsr->page_age_sys_file = + kernfs_walk_and_get(kobj->sd, "workingset_report/page_age"); } EXPORT_SYMBOL_GPL(wsr_register_node); @@ -450,6 +481,14 @@ void wsr_unregister_node(struct node *node) wsr = kobj_to_wsr(kobj); sysfs_remove_group(kobj, &workingset_report_attr_group); + kernfs_put(wsr->page_age_sys_file); wsr_destroy(mem_cgroup_lruvec(NULL, kobj_to_pgdat(kobj))); } EXPORT_SYMBOL_GPL(wsr_unregister_node); + +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); +}