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Date:   Thu, 14 Apr 2022 21:26:06 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Schspa Shi <schspa@gmail.com>
Cc:     dsterba@suse.cz, clm@fb.com, dsterba@suse.com,
        josef@toxicpanda.com, linux-btrfs@vger.kernel.org,
        linux-kernel@vger.kernel.org, terrelln@fb.com
Subject: Re: [PATCH v2] btrfs: zstd: use spin_lock in timer callback
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 <20220411155540.36853-1-schspa@gmail.com>
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On Mon, Apr 11, 2022 at 11:55:41PM +0800, Schspa Shi wrote:
> This is an optimization for fix fee13fe96529 ("btrfs:
> correct zstd workspace manager lock to use spin_lock_bh()")
> 
> The critical region for wsm.lock is only accessed by the process context and
> the softirq context.
> 
> Because in the soft interrupt, the critical section will not be preempted by the
> soft interrupt again, there is no need to call spin_lock_bh(&wsm.lock) to turn
> off the soft interrupt, spin_lock(&wsm.lock) is enough for this situation.
> 
> Changelog:
> v1 -> v2:
> 	- Change the commit message to make it more readable.
> 
> [1] https://lore.kernel.org/all/20220408181523.92322-1-schspa@gmail.com/
> 
> Signed-off-by: Schspa Shi <schspa@gmail.com>

Added to misc-next, thanks.