jbd: Provide function to check whether transaction will issue data barrier

Provide a function which returns whether a transaction with given tid
will send a barrier to the filesystem device. The function will be used
by ext3 to detect whether fsync needs to send a separate barrier or not.

Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara 2010-04-15 22:16:24 +02:00
Родитель 311b9549ed
Коммит 03f4d804a1
3 изменённых файлов: 42 добавлений и 2 удалений

Просмотреть файл

@ -786,6 +786,12 @@ wait_for_iobuf:
jbd_debug(3, "JBD: commit phase 6\n");
/* All metadata is written, now write commit record and do cleanup */
spin_lock(&journal->j_state_lock);
J_ASSERT(commit_transaction->t_state == T_COMMIT);
commit_transaction->t_state = T_COMMIT_RECORD;
spin_unlock(&journal->j_state_lock);
if (journal_write_commit_record(journal, commit_transaction))
err = -EIO;
@ -923,7 +929,7 @@ restart_loop:
jbd_debug(3, "JBD: commit phase 8\n");
J_ASSERT(commit_transaction->t_state == T_COMMIT);
J_ASSERT(commit_transaction->t_state == T_COMMIT_RECORD);
commit_transaction->t_state = T_FINISHED;
J_ASSERT(commit_transaction == journal->j_committing_transaction);

Просмотреть файл

@ -564,6 +564,38 @@ int log_wait_commit(journal_t *journal, tid_t tid)
return err;
}
/*
* Return 1 if a given transaction has not yet sent barrier request
* connected with a transaction commit. If 0 is returned, transaction
* may or may not have sent the barrier. Used to avoid sending barrier
* twice in common cases.
*/
int journal_trans_will_send_data_barrier(journal_t *journal, tid_t tid)
{
int ret = 0;
transaction_t *commit_trans;
if (!(journal->j_flags & JFS_BARRIER))
return 0;
spin_lock(&journal->j_state_lock);
/* Transaction already committed? */
if (tid_geq(journal->j_commit_sequence, tid))
goto out;
/*
* Transaction is being committed and we already proceeded to
* writing commit record?
*/
commit_trans = journal->j_committing_transaction;
if (commit_trans && commit_trans->t_tid == tid &&
commit_trans->t_state >= T_COMMIT_RECORD)
goto out;
ret = 1;
out:
spin_unlock(&journal->j_state_lock);
return ret;
}
EXPORT_SYMBOL(journal_commit_will_send_barrier);
/*
* Log buffer allocation routines:
*/
@ -1157,6 +1189,7 @@ int journal_destroy(journal_t *journal)
{
int err = 0;
/* Wait for the commit thread to wake up and die. */
journal_kill_thread(journal);

Просмотреть файл

@ -427,9 +427,9 @@ struct transaction_s
enum {
T_RUNNING,
T_LOCKED,
T_RUNDOWN,
T_FLUSH,
T_COMMIT,
T_COMMIT_RECORD,
T_FINISHED
} t_state;
@ -991,6 +991,7 @@ int journal_start_commit(journal_t *journal, tid_t *tid);
int journal_force_commit_nested(journal_t *journal);
int log_wait_commit(journal_t *journal, tid_t tid);
int log_do_checkpoint(journal_t *journal);
int journal_trans_will_send_data_barrier(journal_t *journal, tid_t tid);
void __log_wait_for_space(journal_t *journal);
extern void __journal_drop_transaction(journal_t *, transaction_t *);