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Subject: Re: [PATCH -v2] ext4: inline jbd2_journal_[un]register_shrinker()
To:     Theodore Ts'o <tytso@mit.edu>,
        Ext4 Developers List <linux-ext4@vger.kernel.org>
CC:     Jan Kara <jack@suse.cz>, Zhang Yi <yi.zhang@huawei.com>,
        Sachin Sant <sachinp@linux.vnet.ibm.com>,
        linux-tegra <linux-tegra@vger.kernel.org>
References: <3acc3ee6-3a3d-3b26-7580-b20955270913@huawei.com>
 <20210705145025.3363130-1-tytso@mit.edu>
From:   Jon Hunter <jonathanh@nvidia.com>
Message-ID: <ecd3fa6b-7b49-74b8-cdfa-a1f00d92ec51@nvidia.com>
Date:   Mon, 5 Jul 2021 19:29:18 +0100
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On 05/07/2021 15:50, Theodore Ts'o wrote:
> The function jbd2_journal_unregister_shrinker() was getting called
> twice when the file system was getting unmounted.  On Power and ARM
> platforms this was causing kernel crash when unmounting the file
> system, when a percpu_counter was destroyed twice.
> 
> Fix this by removing jbd2_journal_[un]register_shrinker() functions,
> and inlining the shrinker setup and teardown into
> journal_init_common() and jbd2_journal_destroy().  This means that
> ext4 and ocfs2 now no longer need to know about registering and
> unregistering jbd2's shrinker.
> 
> Also, while we're at it, rename the percpu counter from
> j_jh_shrink_count to j_checkpoint_jh_count, since this makes it
> clearer what this counter is intended to track.
> 
> Fixes: 4ba3fcdde7e3 ("jbd2,ext4: add a shrinker to release checkpointed buffers")
> Reported-by: Jon Hunter <jonathanh@nvidia.com>
> Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
> Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
> Reviewed-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Thanks, works for me.

Tested-by: Jon Hunter <jonathanh@nvidia.com>

Cheers
Jon

-- 
nvpublic