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c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1711005150; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1STPLceG9T3wIRgkzS37HGsA0OX/C2ElA4etQjPKAI4=; b=m0pBSqFfJRITYvhHo+Mnxm8LQHrI1eLpogXvBWtWr824N17Jxkr8RizrqR8e8b5RMcO1dF LiBHJSnVLT5GZAI9WZ5f7a3X0O7a/WNuBl7KuyDxuu0lhawL3vldmK2gNFTkNOi6PuuR0h OhAasG2f/15UpELXpWZ4lymPxJE7ceI= Received: from mail.maildlp.com (unknown [172.19.163.216]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4V0c8x2JmCz4f3js3 for ; Thu, 21 Mar 2024 15:12:17 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id 595561A017A for ; Thu, 21 Mar 2024 15:12:23 +0800 (CST) Received: from [10.174.178.129] (unknown [10.174.178.129]) by APP1 (Coremail) with SMTP id cCh0CgAnRQ7V3ftldCd1Hg--.33160S2; Thu, 21 Mar 2024 15:12:23 +0800 (CST) Subject: Re: [PATCH 6/6] writeback: remove unneeded GDTC_INIT_NO_WB To: Tejun Heo Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, willy@infradead.org, bfoster@redhat.com, jack@suse.cz, dsterba@suse.com, mjguzik@gmail.com, dhowells@redhat.com, peterz@infradead.org References: <20240320110222.6564-1-shikemeng@huaweicloud.com> <20240320110222.6564-7-shikemeng@huaweicloud.com> From: Kemeng Shi Message-ID: Date: Thu, 21 Mar 2024 15:12:21 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; 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>> + struct dirty_throttle_control gdtc = { }; > > Even if it's currently not referenced, wouldn't it still be better to always > guarantee that a dtc's dom is always initialized? I'm not sure what we get > by removing this. As we explicitly use GDTC_INIT_NO_WB to set global_wb_domain before calculating dirty limit with domain_dirty_limits, I intuitively think the dirty limit calculation in domain_dirty_limits is related to global_wb_domain when CONFIG_WRITEBACK_CGROUP is enabled while the truth is not. So this is a little confusing to me. Would it be acceptable to you that we keep useing GDTC_INIT_NO_WB but define GDTC_INIT_NO_WB to null fow now and redefine GDTC_INIT_NO_WB when some member of gdtc is really needed. Of couse I'm not insistent on this. Would like to hear you suggestion. Thanks! > > Thanks. >