diff options
| author | Jan Kara <jack@suse.cz> | 2016-09-22 17:44:06 +0200 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2016-09-22 17:44:06 +0200 |
| commit | e03a9976afce6634826d56c33531dd10bb9a9166 (patch) | |
| tree | 5cd08ff2ed8a983a96f485680416e840fd095194 | |
| parent | blockgroup_lock.h: simplify definition of NR_BG_LOCKS (diff) | |
| download | linux-e03a9976afce6634826d56c33531dd10bb9a9166.tar.xz linux-e03a9976afce6634826d56c33531dd10bb9a9166.zip | |
jbd2: fix lockdep annotation in add_transaction_credits()
Thomas has reported a lockdep splat hitting in
add_transaction_credits(). The problem is that that function calls
jbd2_might_wait_for_commit() while holding j_state_lock which is wrong
(we do not really wait for transaction commit while holding that lock).
Fix the problem by moving jbd2_might_wait_for_commit() into places where
we are ready to wait for transaction commit and thus j_state_lock is
unlocked.
Cc: stable@vger.kernel.org
Fixes: 1eaa566d368b214d99cbb973647c1b0b8102a9ae
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| -rw-r--r-- | fs/jbd2/transaction.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index b5bc3e249163..3d8246a9faa4 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -159,6 +159,7 @@ static void wait_transaction_locked(journal_t *journal) read_unlock(&journal->j_state_lock); if (need_to_start) jbd2_log_start_commit(journal, tid); + jbd2_might_wait_for_commit(journal); schedule(); finish_wait(&journal->j_wait_transaction_locked, &wait); } @@ -182,8 +183,6 @@ static int add_transaction_credits(journal_t *journal, int blocks, int needed; int total = blocks + rsv_blocks; - jbd2_might_wait_for_commit(journal); - /* * If the current transaction is locked down for commit, wait * for the lock to be released. @@ -214,6 +213,7 @@ static int add_transaction_credits(journal_t *journal, int blocks, if (atomic_read(&journal->j_reserved_credits) + total > journal->j_max_transaction_buffers) { read_unlock(&journal->j_state_lock); + jbd2_might_wait_for_commit(journal); wait_event(journal->j_wait_reserved, atomic_read(&journal->j_reserved_credits) + total <= journal->j_max_transaction_buffers); @@ -238,6 +238,7 @@ static int add_transaction_credits(journal_t *journal, int blocks, if (jbd2_log_space_left(journal) < jbd2_space_needed(journal)) { atomic_sub(total, &t->t_outstanding_credits); read_unlock(&journal->j_state_lock); + jbd2_might_wait_for_commit(journal); write_lock(&journal->j_state_lock); if (jbd2_log_space_left(journal) < jbd2_space_needed(journal)) __jbd2_log_wait_for_space(journal); @@ -255,6 +256,7 @@ static int add_transaction_credits(journal_t *journal, int blocks, sub_reserved_credits(journal, rsv_blocks); atomic_sub(total, &t->t_outstanding_credits); read_unlock(&journal->j_state_lock); + jbd2_might_wait_for_commit(journal); wait_event(journal->j_wait_reserved, atomic_read(&journal->j_reserved_credits) + rsv_blocks <= journal->j_max_transaction_buffers / 2); |