linux-ext4 - Re: [PATCH] jbd2: modify assert condition in __journal_remove_journal

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Date:   Wed, 22 Jan 2020 09:50:24 +0100
From:   Jan Kara <jack@...e.cz>
To:     Shijie Luo <luoshijie1@...wei.com>
Cc:     linux-ext4@...r.kernel.org, tytso@....edu, jack@...e.cz
Subject: Re: [PATCH] jbd2: modify assert condition in
 __journal_remove_journal_head

On Wed 22-01-20 02:05:48, Shijie Luo wrote:
> Only when jh->b_jcount = 0 in jbd2_journal_put_journal_head, we are allowed
> to call __journal_remove_journal_head.
> 
> Signed-off-by: Shijie Luo <luoshijie1@...wei.com>

Thanks for the patch. You're right but given that
__journal_remove_journal_head() has exactly one caller and that checks for
jh->b_jcount == 0 just before calling __journal_remove_journal_head(), I
think the assertion is pretty pointless. So I'd rather just remove it
completely.

								Honza

> ---
>  fs/jbd2/journal.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
> index 5e408ee24a1a..4f417a7f1ae0 100644
> --- a/fs/jbd2/journal.c
> +++ b/fs/jbd2/journal.c
> @@ -2556,7 +2556,7 @@ static void __journal_remove_journal_head(struct buffer_head *bh)
>  {
>  	struct journal_head *jh = bh2jh(bh);
>  
> -	J_ASSERT_JH(jh, jh->b_jcount >= 0);
> +	J_ASSERT_JH(jh, jh->b_jcount == 0);
>  	J_ASSERT_JH(jh, jh->b_transaction == NULL);
>  	J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
>  	J_ASSERT_JH(jh, jh->b_cp_transaction == NULL);
> -- 
> 2.19.1
> 
-- 
Jan Kara <jack@...e.com>
SUSE Labs, CR