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s=arc-20220608; d=hostedemail.com; t=1711459613; a=rsa-sha256; cv=none; b=2ZHXcqrWIyld1jgQ1RFxCfOYaJ+NaTVjlMWxqLqt9xUOv/NWXWrh21gbllrsiQ3A0lqf32 wwMCUpp0b+rXiCcyI1WAlXTu0qunYp9Bso59DqFBSTa+A15Dhnkmi7gzoGsXkzCL23dKZ/ 1EmMCa0V2FvTzbrUTQSjBm9J6c5plBQ= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=none; spf=pass (imf18.hostedemail.com: domain of shikemeng@huaweicloud.com designates 45.249.212.51 as permitted sender) smtp.mailfrom=shikemeng@huaweicloud.com; dmarc=none Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4V3rDW6DLNz4f3jLG for ; Tue, 26 Mar 2024 21:26:35 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.252]) by mail.maildlp.com (Postfix) with ESMTP id 0089A1A06D7 for ; Tue, 26 Mar 2024 21:26:43 +0800 (CST) Received: from [10.174.178.129] (unknown [10.174.178.129]) by APP3 (Coremail) with SMTP id _Ch0CgA3RJwSzQJmvaESIA--.44448S2; Tue, 26 Mar 2024 21:26:43 +0800 (CST) Subject: Re: [PATCH 2/6] writeback: support retrieving per group debug writeback stats of bdi To: Jan Kara Cc: akpm@linux-foundation.org, tj@kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, willy@infradead.org, bfoster@redhat.com, dsterba@suse.com, mjguzik@gmail.com, dhowells@redhat.com, peterz@infradead.org References: <20240320110222.6564-1-shikemeng@huaweicloud.com> <20240320110222.6564-3-shikemeng@huaweicloud.com> <20240326122421.dofl35cdtgaojt26@quack3> From: Kemeng Shi Message-ID: <206c3800-01ec-2d3b-fe89-cbb1b36158a3@huaweicloud.com> Date: Tue, 26 Mar 2024 21:26:42 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; 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>> + struct dirty_throttle_control mdtc = { MDTC_INIT(wb, &gdtc) }; >> + unsigned long filepages, headroom, writeback; >> + >> + 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, mdtc.thresh); >> +} > > I kind of wish we didn't replicate this logic from balance_dirty_pages() > and wb_over_bg_thresh() into yet another place. But the refactoring would > be kind of difficult. So OK. Thanks for review the code. I have considered about this. It's difficult and will introduce a lot change to non-debug code which make this series uneasy to review. I will submit another patch for refactoring if I could find a way to clean the code. Kemeng > > Honza >