From mboxrd@z Thu Jan 1 00:00:00 1970 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 CE3C118E1D; Tue, 23 Apr 2024 03:46:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713844013; cv=none; b=lHsXJHFA9cvUvA43aeP0G5oAgysAmBwev6KVdX0DsiCK0rrZ3uvTqi6pX8bbEUzV3W2joHm2CyxdiCtco6FzZvygV6V+B9T9l1PQpSeSIIT+E7gT7yMTfb74Uw5j98sYXOZhUq45yIy2KTabZlQS8ytVaLvj7QVr19PmQso8gSE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713844013; c=relaxed/simple; bh=u6Vp1WdZoqKLc2edQMi9qKEIPFcXRKLys3K5tccU18s=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=dOBY7v1N5OVWhIrBWBA7wXzTu4ix2VKNFojCFtef/Q3r61ZCEEkOhWFh4bqYNmCEhivVQ2/qExjkrn862gVhUBLD273Kopvc6dxHhtcKD9qHS0I/+HeQU8qDBHJakiEm5+FfLwqwYidO3c2X7Z8TY5kXNHIAtq1iuYScEvdQpe0= 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=45.249.212.51 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 [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4VNp2N4xp5z4f3nTj; Tue, 23 Apr 2024 11:46:36 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.75]) by mail.maildlp.com (Postfix) with ESMTP id CE1121A0572; Tue, 23 Apr 2024 11:46:45 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.101.6]) by APP2 (Coremail) with SMTP id Syh0CgA3Ww4kLydmKkDYKw--.11241S2; Tue, 23 Apr 2024 11:46:45 +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 v5 0/5] Improve visibility of writeback Date: Tue, 23 Apr 2024 11:46:38 +0800 Message-Id: <20240423034643.141219-1-shikemeng@huaweicloud.com> X-Mailer: git-send-email 2.30.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:Syh0CgA3Ww4kLydmKkDYKw--.11241S2 X-Coremail-Antispam: 1UD129KBjvJXoWxWFy5ur1UAF43ZrWUAw47urg_yoWrXr4fpF Z5Jw15tr4UZ3WxCFn3Ca42gry5Kw48J347Xr9xZrW293Z0qr1Dtr95Wa45AryUCwn3Ary7 JFsxZry8Gr4vgaUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUk2b4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x 0267AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG 6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFV Cjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7MxAIw28I cxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2 IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI 42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42 IY6xAIw20EY4v20xvaj40_WFyUJVCq3wCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E 87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxUrR6zUUUUU X-CM-SenderInfo: 5vklyvpphqwq5kxd4v5lfo033gof0z/ v4->v5: -Add new patch to fix build problem of "writeback: support retrieving per group debug writeback stats of bdi". The new fix patch can be folded into it's pre-patch if the pre-patch is not merge into tree or it could be pick-up to apply. v3->v4: -Fix build warning that filepages, headroom and writeback in cgwb_calc_thresh is used uninitialized when CONFIG_CGROUP_WRITEBACK is not enabled. v2->v3: -Drop patches to protect non-exist race and to define GDTC_INIT_NO_WB to null. -Add wb_tryget to wb from which we collect stats to bdi stats. -Create wb_stats when CONFIG_CGROUP_WRITEBACK is not enabled. -Add a blank line between two wb stats in wb_stats. v1->v2: -Send cleanup to wq_monitor.py separately. -Add patch to avoid use after free of bdi. -Rename wb_calc_cg_thresh to cgwb_calc_thresh as Tejun suggested. -Use rcu walk to avoid use after free. -Add debug output to each related patches. This series tries to improve visilibity of writeback. Patch 1 make /sys/kernel/debug/bdi/xxx/stats show writeback info of whole bdi instead of only writeback info in root cgroup. Patch 2 add a new debug file /sys/kernel/debug/bdi/xxx/wb_stats to show per wb writeback info. Patch 3 add wb_monitor.py to monitor basic writeback info of running system, more info could be added on demand. Patch 4 is a random cleanup. More details can be found in respective patches. Thanks! 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: 4704 kB BdiReclaimable: 1294496 kB BdiDirtyThresh: 204208088 kB DirtyThresh: 195259944 kB BackgroundThresh: 32503588 kB BdiDirtied: 48519296 kB BdiWritten: 47225696 kB BdiWriteBandwidth: 1173892 kBps b_dirty: 1 b_io: 0 b_more_io: 1 b_dirty_time: 0 bdi_list: 1 state: 1 /* 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: 4208 WbWriteback: 59808 kB WbReclaimable: 676480 kB WbDirtyThresh: 6004624 kB WbDirtied: 23348192 kB WbWritten: 22614592 kB WbWriteBandwidth: 593204 kBps b_dirty: 1 b_io: 1 b_more_io: 0 b_dirty_time: 0 state: 7 WbCgIno: 4249 WbWriteback: 144256 kB WbReclaimable: 432096 kB WbDirtyThresh: 6004344 kB WbDirtied: 25727744 kB WbWritten: 25154752 kB WbWriteBandwidth: 577904 kBps b_dirty: 0 b_io: 1 b_more_io: 0 b_dirty_time: 0 state: 7 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 ... Kemeng Shi (5): writeback: collect stats of all wb of bdi in bdi_debug_stats_show writeback: support retrieving per group debug writeback stats of bdi writeback: fix build problems of "writeback: support retrieving per group debug writeback stats of bdi" writeback: add wb_monitor.py script to monitor writeback info on bdi writeback: rename nr_reclaimable to nr_dirty in balance_dirty_pages include/linux/writeback.h | 1 + mm/backing-dev.c | 177 +++++++++++++++++++++++++++++----- mm/page-writeback.c | 27 +++++- tools/writeback/wb_monitor.py | 172 +++++++++++++++++++++++++++++++++ 4 files changed, 348 insertions(+), 29 deletions(-) create mode 100644 tools/writeback/wb_monitor.py -- 2.30.0