From patchwork Mon Apr 22 16:48:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kemeng Shi X-Patchwork-Id: 13637849 Received: from dggsgout12.his.huawei.com (unknown [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 22E2C4CE1F; Mon, 22 Apr 2024 07:52:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713772369; cv=none; b=jvRHUrXYnkJJEZobt36W/F2N+lSM9alZUS+z6wW32J65GQsJrPJ4NHRp52GeLHPjPVIzPgGcEguo9vufkngf6+WRpVLJdj5N6ns25BrfpkRxw0GiZA9/07xyAxRMUeJBxjaowtdaO8yfgxOW4kBDPaw7c+FAvBOupWqgql0TWok= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713772369; c=relaxed/simple; bh=wXjkXQMpSmH/huNriZnTVvdgYaHBs6dlp13TGKPwUMk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=urxyUFoUUVYwCN+imiIqqxgQmVb0TYBC7AJ+txG+g4DaAKmlIME9vqgpwXkVwMvTH/W/+5mGCpRvH6uW+iY485bJkAD9ZgdgTJD+RmyuBavwBlkQAVu6pARMydG8CrI8rVf+HJnNfi9oxqdpViqoSts5IL5QutIjoJpb05awpOg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4VNHXh0xStz4f3khk; Mon, 22 Apr 2024 15:52:36 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.75]) by mail.maildlp.com (Postfix) with ESMTP id 8C3AD1A0568; Mon, 22 Apr 2024 15:52:43 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.101.6]) by APP2 (Coremail) with SMTP id Syh0CgCHqg1JFyZmCViLKw--.3978S3; Mon, 22 Apr 2024 15:52:43 +0800 (CST) From: Kemeng Shi To: akpm@linux-foundation.org, willy@infradead.org, jack@suse.cz, bfoster@redhat.com, tj@kernel.org Cc: dsterba@suse.com, mjguzik@gmail.com, dhowells@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v4 1/4] writeback: collect stats of all wb of bdi in bdi_debug_stats_show Date: Tue, 23 Apr 2024 00:48:05 +0800 Message-Id: <20240422164808.13627-2-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20240422164808.13627-1-shikemeng@huaweicloud.com> References: <20240422164808.13627-1-shikemeng@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: Syh0CgCHqg1JFyZmCViLKw--.3978S3 X-Coremail-Antispam: 1UD129KBjvJXoW3Jr4kKF15Jw13GF4rGF13twb_yoW7ArWxpF ZxGw1fJrWxZFyfWasxZFWDXrW5tw40q342qF97C3y5K3WDAFy3KFyxua4jyr1UGFZ7JFy3 Jan8ArykC3yUKF7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmqb4IE77IF4wAFF20E14v26ryj6rWUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M280x2IEY4vEnII2IxkI6r1a6r45M2 8IrcIa0xkI8VA2jI8067AKxVWUGwA2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK 0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4 x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l 84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I 8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AK xVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxV A2Y2ka0xkIwI1lc7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC 6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWw C2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_ JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJV WUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIY CTnIWIevJa73UjIFyTuYvjxU3AwsUUUUU X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ /sys/kernel/debug/bdi/xxx/stats is supposed to show writeback information of whole bdi, but only writeback information of bdi in root cgroup is collected. So writeback information in non-root cgroup are missing now. To be more specific, considering following case: /* create writeback cgroup */ cd /sys/fs/cgroup echo "+memory +io" > cgroup.subtree_control mkdir group1 cd group1 echo $$ > cgroup.procs /* do writeback in cgroup */ fio -name test -filename=/dev/vdb ... /* get writeback info of bdi */ cat /sys/kernel/debug/bdi/xxx/stats The cat result unexpectedly implies that there is no writeback on target bdi. Fix this by collecting stats of all wb in bdi instead of only wb in root cgroup. Following domain hierarchy is tested: global domain (320G) / \ cgroup domain1(10G) cgroup domain2(10G) | | bdi wb1 wb2 /* all writeback info of bdi is successfully collected */ cat stats BdiWriteback: 2912 kB BdiReclaimable: 1598464 kB BdiDirtyThresh: 167479028 kB DirtyThresh: 195038532 kB BackgroundThresh: 32466728 kB BdiDirtied: 19141696 kB BdiWritten: 17543456 kB BdiWriteBandwidth: 1136172 kBps b_dirty: 2 b_io: 0 b_more_io: 1 b_dirty_time: 0 bdi_list: 1 state: 1 Signed-off-by: Kemeng Shi Acked-by: Tejun Heo --- mm/backing-dev.c | 96 ++++++++++++++++++++++++++++++++++++------------ 1 file changed, 73 insertions(+), 23 deletions(-) diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 5fa3666356f9..089146feb830 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -39,6 +39,19 @@ struct workqueue_struct *bdi_wq; #include #include +struct wb_stats { + unsigned long nr_dirty; + unsigned long nr_io; + unsigned long nr_more_io; + unsigned long nr_dirty_time; + unsigned long nr_writeback; + unsigned long nr_reclaimable; + unsigned long nr_dirtied; + unsigned long nr_written; + unsigned long dirty_thresh; + unsigned long wb_thresh; +}; + static struct dentry *bdi_debug_root; static void bdi_debug_init(void) @@ -46,31 +59,68 @@ static void bdi_debug_init(void) bdi_debug_root = debugfs_create_dir("bdi", NULL); } -static int bdi_debug_stats_show(struct seq_file *m, void *v) +static void collect_wb_stats(struct wb_stats *stats, + struct bdi_writeback *wb) { - struct backing_dev_info *bdi = m->private; - struct bdi_writeback *wb = &bdi->wb; - unsigned long background_thresh; - unsigned long dirty_thresh; - unsigned long wb_thresh; - unsigned long nr_dirty, nr_io, nr_more_io, nr_dirty_time; struct inode *inode; - nr_dirty = nr_io = nr_more_io = nr_dirty_time = 0; spin_lock(&wb->list_lock); list_for_each_entry(inode, &wb->b_dirty, i_io_list) - nr_dirty++; + stats->nr_dirty++; list_for_each_entry(inode, &wb->b_io, i_io_list) - nr_io++; + stats->nr_io++; list_for_each_entry(inode, &wb->b_more_io, i_io_list) - nr_more_io++; + stats->nr_more_io++; list_for_each_entry(inode, &wb->b_dirty_time, i_io_list) if (inode->i_state & I_DIRTY_TIME) - nr_dirty_time++; + stats->nr_dirty_time++; spin_unlock(&wb->list_lock); + stats->nr_writeback += wb_stat(wb, WB_WRITEBACK); + stats->nr_reclaimable += wb_stat(wb, WB_RECLAIMABLE); + stats->nr_dirtied += wb_stat(wb, WB_DIRTIED); + stats->nr_written += wb_stat(wb, WB_WRITTEN); + stats->wb_thresh += wb_calc_thresh(wb, stats->dirty_thresh); +} + +#ifdef CONFIG_CGROUP_WRITEBACK +static void bdi_collect_stats(struct backing_dev_info *bdi, + struct wb_stats *stats) +{ + struct bdi_writeback *wb; + + rcu_read_lock(); + list_for_each_entry_rcu(wb, &bdi->wb_list, bdi_node) { + if (!wb_tryget(wb)) + continue; + + collect_wb_stats(stats, wb); + wb_put(wb); + } + rcu_read_unlock(); +} +#else +static void bdi_collect_stats(struct backing_dev_info *bdi, + struct wb_stats *stats) +{ + collect_wb_stats(stats, &bdi->wb); +} +#endif + +static int bdi_debug_stats_show(struct seq_file *m, void *v) +{ + struct backing_dev_info *bdi = m->private; + unsigned long background_thresh; + unsigned long dirty_thresh; + struct wb_stats stats; + unsigned long tot_bw; + global_dirty_limits(&background_thresh, &dirty_thresh); - wb_thresh = wb_calc_thresh(wb, dirty_thresh); + + memset(&stats, 0, sizeof(stats)); + stats.dirty_thresh = dirty_thresh; + bdi_collect_stats(bdi, &stats); + tot_bw = atomic_long_read(&bdi->tot_write_bandwidth); seq_printf(m, "BdiWriteback: %10lu kB\n" @@ -87,18 +137,18 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v) "b_dirty_time: %10lu\n" "bdi_list: %10u\n" "state: %10lx\n", - (unsigned long) K(wb_stat(wb, WB_WRITEBACK)), - (unsigned long) K(wb_stat(wb, WB_RECLAIMABLE)), - K(wb_thresh), + K(stats.nr_writeback), + K(stats.nr_reclaimable), + K(stats.wb_thresh), K(dirty_thresh), K(background_thresh), - (unsigned long) K(wb_stat(wb, WB_DIRTIED)), - (unsigned long) K(wb_stat(wb, WB_WRITTEN)), - (unsigned long) K(wb->write_bandwidth), - nr_dirty, - nr_io, - nr_more_io, - nr_dirty_time, + K(stats.nr_dirtied), + K(stats.nr_written), + K(tot_bw), + stats.nr_dirty, + stats.nr_io, + stats.nr_more_io, + stats.nr_dirty_time, !list_empty(&bdi->bdi_list), bdi->wb.state); 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Mon, 22 Apr 2024 15:52:43 +0800 (CST) From: Kemeng Shi To: akpm@linux-foundation.org, willy@infradead.org, jack@suse.cz, bfoster@redhat.com, tj@kernel.org Cc: dsterba@suse.com, mjguzik@gmail.com, dhowells@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v4 2/4] writeback: support retrieving per group debug writeback stats of bdi Date: Tue, 23 Apr 2024 00:48:06 +0800 Message-Id: <20240422164808.13627-3-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20240422164808.13627-1-shikemeng@huaweicloud.com> References: <20240422164808.13627-1-shikemeng@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: Syh0CgCHqg1JFyZmCViLKw--.3978S4 X-Coremail-Antispam: 1UD129KBjvJXoW3Xw15uFyfXw1UKFWkCF1xZrb_yoW7uw15pa 98Gw15Jr4UZr17WFZxAay2qry5tw48trW7X3s7Z3yftFnrtry3tFy8ury8Ary5AF93AFy3 Jan8Cry8GrWkKrJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPab4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M280x2IEY4vEnII2IxkI6r1a6r45M2 8IrcIa0xkI8VA2jI8067AKxVWUXwA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK 0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4 x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l 84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I 8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AK xVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxV A2Y2ka0xkIwI1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAq x4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r 43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF 7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxV WUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxU ImhFDUUUU X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ Add /sys/kernel/debug/bdi/xxx/wb_stats to show per group writeback stats of bdi. Following domain hierarchy is tested: global domain (320G) / \ cgroup domain1(10G) cgroup domain2(10G) | | bdi wb1 wb2 /* per wb writeback info of bdi is collected */ cat /sys/kernel/debug/bdi/252:16/wb_stats WbCgIno: 1 WbWriteback: 0 kB WbReclaimable: 0 kB WbDirtyThresh: 0 kB WbDirtied: 0 kB WbWritten: 0 kB WbWriteBandwidth: 102400 kBps b_dirty: 0 b_io: 0 b_more_io: 0 b_dirty_time: 0 state: 1 WbCgIno: 4094 WbWriteback: 54432 kB WbReclaimable: 766080 kB WbDirtyThresh: 3094760 kB WbDirtied: 1656480 kB WbWritten: 837088 kB WbWriteBandwidth: 132772 kBps b_dirty: 1 b_io: 1 b_more_io: 0 b_dirty_time: 0 state: 7 WbCgIno: 4135 WbWriteback: 15232 kB WbReclaimable: 786688 kB WbDirtyThresh: 2909984 kB WbDirtied: 1482656 kB WbWritten: 681408 kB WbWriteBandwidth: 124848 kBps b_dirty: 0 b_io: 1 b_more_io: 0 b_dirty_time: 0 state: 7 Signed-off-by: Kemeng Shi Acked-by: Tejun Heo --- include/linux/writeback.h | 1 + mm/backing-dev.c | 78 ++++++++++++++++++++++++++++++++++++++- mm/page-writeback.c | 19 ++++++++++ 3 files changed, 96 insertions(+), 2 deletions(-) diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 9845cb62e40b..112d806ddbe4 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -355,6 +355,7 @@ int dirtytime_interval_handler(struct ctl_table *table, int write, void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty); unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh); +unsigned long cgwb_calc_thresh(struct bdi_writeback *wb); void wb_update_bandwidth(struct bdi_writeback *wb); diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 089146feb830..6ecd11bdce6e 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -155,19 +155,93 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v) } DEFINE_SHOW_ATTRIBUTE(bdi_debug_stats); +static void wb_stats_show(struct seq_file *m, struct bdi_writeback *wb, + struct wb_stats *stats) +{ + + seq_printf(m, + "WbCgIno: %10lu\n" + "WbWriteback: %10lu kB\n" + "WbReclaimable: %10lu kB\n" + "WbDirtyThresh: %10lu kB\n" + "WbDirtied: %10lu kB\n" + "WbWritten: %10lu kB\n" + "WbWriteBandwidth: %10lu kBps\n" + "b_dirty: %10lu\n" + "b_io: %10lu\n" + "b_more_io: %10lu\n" + "b_dirty_time: %10lu\n" + "state: %10lx\n\n", + cgroup_ino(wb->memcg_css->cgroup), + K(stats->nr_writeback), + K(stats->nr_reclaimable), + K(stats->wb_thresh), + K(stats->nr_dirtied), + K(stats->nr_written), + K(wb->avg_write_bandwidth), + stats->nr_dirty, + stats->nr_io, + stats->nr_more_io, + stats->nr_dirty_time, + wb->state); +} + +static int cgwb_debug_stats_show(struct seq_file *m, void *v) +{ + struct backing_dev_info *bdi = m->private; + unsigned long background_thresh; + unsigned long dirty_thresh; + struct bdi_writeback *wb; + struct wb_stats stats; + + global_dirty_limits(&background_thresh, &dirty_thresh); + + rcu_read_lock(); + list_for_each_entry_rcu(wb, &bdi->wb_list, bdi_node) { + struct wb_stats stats = { .dirty_thresh = dirty_thresh }; + + if (!wb_tryget(wb)) + continue; + + collect_wb_stats(&stats, wb); + + /* + * Calculate thresh of wb in writeback cgroup which is min of + * thresh in global domain and thresh in cgroup domain. Drop + * rcu lock because cgwb_calc_thresh may sleep in + * cgroup_rstat_flush. We can do so here because we have a ref. + */ + if (mem_cgroup_wb_domain(wb)) { + rcu_read_unlock(); + stats.wb_thresh = min(stats.wb_thresh, cgwb_calc_thresh(wb)); + rcu_read_lock(); + } + + wb_stats_show(m, wb, &stats); + + wb_put(wb); + } + rcu_read_unlock(); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(cgwb_debug_stats); + static void bdi_debug_register(struct backing_dev_info *bdi, const char *name) { bdi->debug_dir = debugfs_create_dir(name, bdi_debug_root); debugfs_create_file("stats", 0444, bdi->debug_dir, bdi, &bdi_debug_stats_fops); + debugfs_create_file("wb_stats", 0444, bdi->debug_dir, bdi, + &cgwb_debug_stats_fops); } static void bdi_debug_unregister(struct backing_dev_info *bdi) { debugfs_remove_recursive(bdi->debug_dir); } -#else +#else /* CONFIG_DEBUG_FS */ static inline void bdi_debug_init(void) { } @@ -178,7 +252,7 @@ static inline void bdi_debug_register(struct backing_dev_info *bdi, static inline void bdi_debug_unregister(struct backing_dev_info *bdi) { } -#endif +#endif /* CONFIG_DEBUG_FS */ static ssize_t read_ahead_kb_store(struct device *dev, struct device_attribute *attr, diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 3e19b87049db..3bb3bed102ef 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -892,6 +892,25 @@ unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh) return __wb_calc_thresh(&gdtc); } +unsigned long cgwb_calc_thresh(struct bdi_writeback *wb) +{ + struct dirty_throttle_control gdtc = { GDTC_INIT_NO_WB }; + struct dirty_throttle_control mdtc = { MDTC_INIT(wb, &gdtc) }; + unsigned long filepages = 0, headroom = 0, writeback = 0; + + gdtc.avail = global_dirtyable_memory(); + gdtc.dirty = global_node_page_state(NR_FILE_DIRTY) + + global_node_page_state(NR_WRITEBACK); + + mem_cgroup_wb_stats(wb, &filepages, &headroom, + &mdtc.dirty, &writeback); + mdtc.dirty += writeback; + mdtc_calc_avail(&mdtc, filepages, headroom); + domain_dirty_limits(&mdtc); + + return __wb_calc_thresh(&mdtc); +} + /* * setpoint - dirty 3 * f(dirty) := 1.0 + (----------------) From patchwork Mon Apr 22 16:48:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kemeng Shi X-Patchwork-Id: 13637851 Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C8D0E4D13F; 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dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4VNHXl4sykz4f3kjt; Mon, 22 Apr 2024 15:52:39 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.75]) by mail.maildlp.com (Postfix) with ESMTP id 74BA11A0572; Mon, 22 Apr 2024 15:52:44 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.101.6]) by APP2 (Coremail) with SMTP id Syh0CgCHqg1JFyZmCViLKw--.3978S5; Mon, 22 Apr 2024 15:52:44 +0800 (CST) From: Kemeng Shi To: akpm@linux-foundation.org, willy@infradead.org, jack@suse.cz, bfoster@redhat.com, tj@kernel.org Cc: dsterba@suse.com, mjguzik@gmail.com, dhowells@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v4 3/4] writeback: add wb_monitor.py script to monitor writeback info on bdi Date: Tue, 23 Apr 2024 00:48:07 +0800 Message-Id: <20240422164808.13627-4-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20240422164808.13627-1-shikemeng@huaweicloud.com> References: <20240422164808.13627-1-shikemeng@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: Syh0CgCHqg1JFyZmCViLKw--.3978S5 X-Coremail-Antispam: 1UD129KBjvJXoW3Xr1UCrWrWFWxXw1DJFy7Jrb_yoWxJr1fpF s8Aw13Ar1xZa4xJrnY9a40vry5Cws5Cr17XrW7ArWakan8Wa4FyryrCFyUAry3Cr9rJ39x X3ya93y8KFWjgFJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmqb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M280x2IEY4vEnII2IxkI6r1a6r45M2 8IrcIa0xkI8VA2jI8067AKxVWUWwA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK 0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4 x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l 84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I 8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AK xVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxV A2Y2ka0xkIwI1lc7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC 6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWw C2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_ JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJV WUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIY CTnIWIevJa73UjIFyTuYvjxUIyxRDUUUU X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ Add wb_monitor.py script to monitor writeback information on backing dev which makes it easier and more convenient to observe writeback behaviors of running system. The wb_monitor.py script is written based on wq_monitor.py. Following domain hierarchy is tested: global domain (320G) / \ cgroup domain1(10G) cgroup domain2(10G) | | bdi wb1 wb2 The wb_monitor.py script output is as following: ./wb_monitor.py 252:16 -c writeback reclaimable dirtied written avg_bw 252:16_1 0 0 0 0 102400 252:16_4284 672 820064 9230368 8410304 685612 252:16_4325 896 819840 10491264 9671648 652348 252:16 1568 1639904 19721632 18081952 1440360 writeback reclaimable dirtied written avg_bw 252:16_1 0 0 0 0 102400 252:16_4284 672 820064 9230368 8410304 685612 252:16_4325 896 819840 10491264 9671648 652348 252:16 1568 1639904 19721632 18081952 1440360 ... Signed-off-by: Kemeng Shi Suggested-by: Tejun Heo Acked-by: Tejun Heo --- tools/writeback/wb_monitor.py | 172 ++++++++++++++++++++++++++++++++++ 1 file changed, 172 insertions(+) create mode 100644 tools/writeback/wb_monitor.py diff --git a/tools/writeback/wb_monitor.py b/tools/writeback/wb_monitor.py new file mode 100644 index 000000000000..5e3591f1f9a9 --- /dev/null +++ b/tools/writeback/wb_monitor.py @@ -0,0 +1,172 @@ +#!/usr/bin/env drgn +# +# Copyright (C) 2024 Kemeng Shi +# Copyright (C) 2024 Huawei Inc + +desc = """ +This is a drgn script based on wq_monitor.py to monitor writeback info on +backing dev. For more info on drgn, visit https://github.com/osandov/drgn. + + writeback(kB) Amount of dirty pages are currently being written back to + disk. + + reclaimable(kB) Amount of pages are currently reclaimable. + + dirtied(kB) Amount of pages have been dirtied. + + wrttien(kB) Amount of dirty pages have been written back to disk. + + avg_wb(kBps) Smoothly estimated write bandwidth of writing dirty pages + back to disk. +""" + +import signal +import re +import time +import json + +import drgn +from drgn.helpers.linux.list import list_for_each_entry + +import argparse +parser = argparse.ArgumentParser(description=desc, + formatter_class=argparse.RawTextHelpFormatter) +parser.add_argument('bdi', metavar='REGEX', nargs='*', + help='Target backing device name patterns (all if empty)') +parser.add_argument('-i', '--interval', metavar='SECS', type=float, default=1, + help='Monitoring interval (0 to print once and exit)') +parser.add_argument('-j', '--json', action='store_true', + help='Output in json') +parser.add_argument('-c', '--cgroup', action='store_true', + help='show writeback of bdi in cgroup') +args = parser.parse_args() + +bdi_list = prog['bdi_list'] + +WB_RECLAIMABLE = prog['WB_RECLAIMABLE'] +WB_WRITEBACK = prog['WB_WRITEBACK'] +WB_DIRTIED = prog['WB_DIRTIED'] +WB_WRITTEN = prog['WB_WRITTEN'] +NR_WB_STAT_ITEMS = prog['NR_WB_STAT_ITEMS'] + +PAGE_SHIFT = prog['PAGE_SHIFT'] + +def K(x): + return x << (PAGE_SHIFT - 10) + +class Stats: + def dict(self, now): + return { 'timestamp' : now, + 'name' : self.name, + 'writeback' : self.stats[WB_WRITEBACK], + 'reclaimable' : self.stats[WB_RECLAIMABLE], + 'dirtied' : self.stats[WB_DIRTIED], + 'written' : self.stats[WB_WRITTEN], + 'avg_wb' : self.avg_bw, } + + def table_header_str(): + return f'{"":>16} {"writeback":>10} {"reclaimable":>12} ' \ + f'{"dirtied":>9} {"written":>9} {"avg_bw":>9}' + + def table_row_str(self): + out = f'{self.name[-16:]:16} ' \ + f'{self.stats[WB_WRITEBACK]:10} ' \ + f'{self.stats[WB_RECLAIMABLE]:12} ' \ + f'{self.stats[WB_DIRTIED]:9} ' \ + f'{self.stats[WB_WRITTEN]:9} ' \ + f'{self.avg_bw:9} ' + return out + + def show_header(): + if Stats.table_fmt: + print() + print(Stats.table_header_str()) + + def show_stats(self): + if Stats.table_fmt: + print(self.table_row_str()) + else: + print(self.dict(Stats.now)) + +class WbStats(Stats): + def __init__(self, wb): + bdi_name = wb.bdi.dev_name.string_().decode() + # avoid to use bdi.wb.memcg_css which is only defined when + # CONFIG_CGROUP_WRITEBACK is enabled + if wb == wb.bdi.wb.address_of_(): + ino = "1" + else: + ino = str(wb.memcg_css.cgroup.kn.id.value_()) + self.name = bdi_name + '_' + ino + + self.stats = [0] * NR_WB_STAT_ITEMS + for i in range(NR_WB_STAT_ITEMS): + if wb.stat[i].count >= 0: + self.stats[i] = int(K(wb.stat[i].count)) + else: + self.stats[i] = 0 + + self.avg_bw = int(K(wb.avg_write_bandwidth)) + +class BdiStats(Stats): + def __init__(self, bdi): + self.name = bdi.dev_name.string_().decode() + self.stats = [0] * NR_WB_STAT_ITEMS + self.avg_bw = 0 + + def collectStats(self, wb_stats): + for i in range(NR_WB_STAT_ITEMS): + self.stats[i] += wb_stats.stats[i] + + self.avg_bw += wb_stats.avg_bw + +exit_req = False + +def sigint_handler(signr, frame): + global exit_req + exit_req = True + +def main(): + # handle args + Stats.table_fmt = not args.json + interval = args.interval + cgroup = args.cgroup + + re_str = None + if args.bdi: + for r in args.bdi: + if re_str is None: + re_str = r + else: + re_str += '|' + r + + filter_re = re.compile(re_str) if re_str else None + + # monitoring loop + signal.signal(signal.SIGINT, sigint_handler) + + while not exit_req: + Stats.now = time.time() + + Stats.show_header() + for bdi in list_for_each_entry('struct backing_dev_info', bdi_list.address_of_(), 'bdi_list'): + bdi_stats = BdiStats(bdi) + if filter_re and not filter_re.search(bdi_stats.name): + continue + + for wb in list_for_each_entry('struct bdi_writeback', bdi.wb_list.address_of_(), 'bdi_node'): + wb_stats = WbStats(wb) + bdi_stats.collectStats(wb_stats) + if cgroup: + wb_stats.show_stats() + + bdi_stats.show_stats() + if cgroup and Stats.table_fmt: + print() + + if interval == 0: + break + time.sleep(interval) + +if __name__ == "__main__": + main() From patchwork Mon Apr 22 16:48:08 2024 Content-Type: text/plain; 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smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4VNHXg5k5Lz4f3n5g; Mon, 22 Apr 2024 15:52:35 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.75]) by mail.maildlp.com (Postfix) with ESMTP id E12561A016E; Mon, 22 Apr 2024 15:52:44 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.101.6]) by APP2 (Coremail) with SMTP id Syh0CgCHqg1JFyZmCViLKw--.3978S6; Mon, 22 Apr 2024 15:52:44 +0800 (CST) From: Kemeng Shi To: akpm@linux-foundation.org, willy@infradead.org, jack@suse.cz, bfoster@redhat.com, tj@kernel.org Cc: dsterba@suse.com, mjguzik@gmail.com, dhowells@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v4 4/4] writeback: rename nr_reclaimable to nr_dirty in balance_dirty_pages Date: Tue, 23 Apr 2024 00:48:08 +0800 Message-Id: <20240422164808.13627-5-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20240422164808.13627-1-shikemeng@huaweicloud.com> References: <20240422164808.13627-1-shikemeng@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: Syh0CgCHqg1JFyZmCViLKw--.3978S6 X-Coremail-Antispam: 1UD129KBjvJXoW7WFyxZr1fGF17CrW8WFWkXrb_yoW8Cr15pF ZrGw1jkr4xtayavrn3CFWq9rZxtw48tF43JryUCw4SvwsrWF1UKFyI9ry0vF1xAa4fJrWa vws0qrykJw1vkrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmCb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M280x2IEY4vEnII2IxkI6r1a6r45M2 8IrcIa0xkI8VA2jI8067AKxVWUAVCq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAv FVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWDJVCq3w A2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE 3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr2 1l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv 67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7 CjxVA2Y2ka0xkIwI1lc7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E 4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGV WUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_ Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26F4j6r4UJwCI42IY6xAIw20EY4v20xvaj4 0_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_ Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07jVUDXUUUUU= X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ Commit 8d92890bd6b85 ("mm/writeback: discard NR_UNSTABLE_NFS, use NR_WRITEBACK instead") removed NR_UNSTABLE_NFS and nr_reclaimable only contains dirty page now. Rename nr_reclaimable to nr_dirty properly. Signed-off-by: Kemeng Shi Reviewed-by: Jan Kara Acked-by: Tejun Heo --- mm/page-writeback.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 3bb3bed102ef..44df5c899a33 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -1694,7 +1694,7 @@ static int balance_dirty_pages(struct bdi_writeback *wb, struct dirty_throttle_control * const mdtc = mdtc_valid(&mdtc_stor) ? &mdtc_stor : NULL; struct dirty_throttle_control *sdtc; - unsigned long nr_reclaimable; /* = file_dirty */ + unsigned long nr_dirty; long period; long pause; long max_pause; @@ -1715,9 +1715,9 @@ static int balance_dirty_pages(struct bdi_writeback *wb, unsigned long m_thresh = 0; unsigned long m_bg_thresh = 0; - nr_reclaimable = global_node_page_state(NR_FILE_DIRTY); + nr_dirty = global_node_page_state(NR_FILE_DIRTY); gdtc->avail = global_dirtyable_memory(); - gdtc->dirty = nr_reclaimable + global_node_page_state(NR_WRITEBACK); + gdtc->dirty = nr_dirty + global_node_page_state(NR_WRITEBACK); domain_dirty_limits(gdtc); @@ -1768,7 +1768,7 @@ static int balance_dirty_pages(struct bdi_writeback *wb, * In normal mode, we start background writeout at the lower * background_thresh, to keep the amount of dirty memory low. */ - if (!laptop_mode && nr_reclaimable > gdtc->bg_thresh && + if (!laptop_mode && nr_dirty > gdtc->bg_thresh && !writeback_in_progress(wb)) wb_start_background_writeback(wb);