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Date:   Mon, 10 Apr 2023 21:36:18 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     yizhou.tang@shopee.com
Cc:     neilb@suse.com, tj@kernel.org, wufengguang@huawei.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        tangyeechou@gmail.com, chunguang.xu@shopee.com, yue.zhao@shopee.com
Subject: Re: [PATCH] mm: Fix memcg writeback for rt tasks
Message-Id: <20230410213618.0d8b2b19a15376dfd49e3c53@linux-foundation.org>
In-Reply-To: <20230403165708.352841-1-yizhou.tang@shopee.com>
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On Tue,  4 Apr 2023 00:57:08 +0800 yizhou.tang@shopee.com wrote:

> From: Tang Yizhou <yizhou.tang@shopee.com>
> 
> Neil said he didn't know what was wanted for realtime in the commit
> message of commit a37b0715ddf3 ("mm/writeback: replace PF_LESS_THROTTLE
> with PF_LOCAL_THROTTLE"). I think we need to distinguish between the
> global writeback and memcg writeback in domain_dirty_limits() for the
> rt tasks.

Why do you think this?

> Fixes: a53eaff8c119 ("MM: increase safety margin provided by PF_LESS_THROTTLE")

In what way does it fix it?  Please describe the user-visible effects
of this change.