Commit 1eaa566d authored by Jan Kara's avatar Jan Kara Committed by Theodore Ts'o
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jbd2: track more dependencies on transaction commit 



So far we were tracking only dependency on transaction commit due to
starting a new handle (which may require commit to start a new
transaction). Now add tracking also for other cases where we wait for
transaction commit. This way lockdep can catch deadlocks e. g. because we
call jbd2_journal_stop() for a synchronous handle with some locks held
which rank below transaction start.

Signed-off-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent ab714aff

fs/jbd2/journal.c

+1 −0
Original line number Diff line number Diff line
@@ -691,6 +691,7 @@ int jbd2_log_wait_commit(journal_t *journal, tid_t tid) 
{

	int err = 0;



	jbd2_might_wait_for_commit(journal);

	read_lock(&journal->j_state_lock);

#ifdef CONFIG_JBD2_DEBUG

	if (!tid_geq(journal->j_commit_request, tid)) {

fs/jbd2/transaction.c

+4 −0
Original line number Diff line number Diff line
@@ -182,6 +182,8 @@ 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.
@@ -695,6 +697,8 @@ void jbd2_journal_lock_updates(journal_t *journal) 
{

	DEFINE_WAIT(wait);



	jbd2_might_wait_for_commit(journal);



	write_lock(&journal->j_state_lock);

	++journal->j_barrier_count;

include/linux/jbd2.h

+6 −0
Original line number Diff line number Diff line
@@ -1046,6 +1046,12 @@ struct journal_s 
#endif

};



#define jbd2_might_wait_for_commit(j) \

	do { \

		rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \

		rwsem_release(&j->j_trans_commit_map, 1, _THIS_IP_); \

	} while (0)



/* journal feature predicate functions */

#define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \

static inline bool jbd2_has_feature_##name(journal_t *j) \

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