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Subject: Re: [PATCH v4] f2fs: fix long latency due to discard during umount
To:     Sahitya Tummala <stummala@codeaurora.org>,
        Jaegeuk Kim <jaegeuk@kernel.org>,
        <linux-f2fs-devel@lists.sourceforge.net>
CC:     <linux-kernel@vger.kernel.org>
References: <1586921462-12972-1-git-send-email-stummala@codeaurora.org>
From:   Chao Yu <yuchao0@huawei.com>
Message-ID: <156892a9-1d19-81b9-e8a2-bc8483385a8b@huawei.com>
Date:   Wed, 15 Apr 2020 14:25:09 +0800
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On 2020/4/15 11:31, Sahitya Tummala wrote:
> F2FS already has a default timeout of 5 secs for discards that
> can be issued during umount, but it can take more than the 5 sec
> timeout if the underlying UFS device queue is already full and there
> are no more available free tags to be used. Fix this by submitting a
> small batch of discard requests so that it won't cause the device
> queue to be full at any time and thus doesn't incur its wait time
> in the umount context.
> 
> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>

Reviewed-by: Chao Yu <yuchao0@huawei.com>

Thanks,