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Date:   Mon, 25 Jul 2022 18:02:05 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>,
        Ioannis Angelakopoulos <iangelak@fb.com>,
        linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] btrfs: Fix unused variable in load_free_space_cache()
Message-ID: <20220725160205.GA13489@twin.jikos.cz>
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        Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
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        Ioannis Angelakopoulos <iangelak@fb.com>,
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References: <20220722163854.1189931-1-nathan@kernel.org>
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On Fri, Jul 22, 2022 at 09:38:54AM -0700, Nathan Chancellor wrote:
> When CONFIG_LOCKDEP is unset, there is a warning about the mapping
> variable being unused:
> 
>   fs/btrfs/free-space-cache.c:929:24: warning: variable 'mapping' set but not used [-Wunused-but-set-variable]
>           struct address_space *mapping;
>                                 ^
>   1 warning generated.
> 
> lockdep_set_class() does not do anything with the first parameter to the
> macro when CONFIG_LOCKDEP is not set so just eliminate the mapping
> variable and use inode instead, which is always used in the function.
> 
> Fixes: 22d85ab1af7d ("btrfs: Change the lockdep class of struct inode's invalidate_lock")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1672
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>

Folded to the patch, thanks.