journal_unmap_buffer() checks first whether the buffer head is a journal. If so it takes locks and then invokes jbd2_journal_grab_journal_head() followed by another check whether this is journal head buffer.
The double checking is pointless. Replace the initial check with jbd2_journal_grab_journal_head() which alredy checks whether the buffer head is actually a journal. Allows also early access to the journal head pointer for the upcoming conversion of state lock to a regular spinlock. Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: "Theodore Ts'o" <[email protected]> Cc: Jan Kara <[email protected]> --- V2: New patch --- fs/jbd2/transaction.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -2196,7 +2196,8 @@ static int journal_unmap_buffer(journal_ * holding the page lock. --sct */ - if (!buffer_jbd(bh)) + jh = jbd2_journal_grab_journal_head(bh); + if (!jh) goto zap_buffer_unlocked; /* OK, we have data buffer in journaled mode */ @@ -2204,10 +2205,6 @@ static int journal_unmap_buffer(journal_ jbd_lock_bh_state(bh); spin_lock(&journal->j_list_lock); - jh = jbd2_journal_grab_journal_head(bh); - if (!jh) - goto zap_buffer_no_jh; - /* * We cannot remove the buffer from checkpoint lists until the * transaction adding inode to orphan list (let's call it T) @@ -2329,7 +2326,6 @@ static int journal_unmap_buffer(journal_ */ jh->b_modified = 0; jbd2_journal_put_journal_head(jh); -zap_buffer_no_jh: spin_unlock(&journal->j_list_lock); jbd_unlock_bh_state(bh); write_unlock(&journal->j_state_lock);
