jbd2: optimize jbd2_journal_force_commit

Current implementation of jbd2_journal_force_commit() is suboptimal because
result in empty and useless commits. But callers just want to force and wait
any unfinished commits. We already have jbd2_journal_force_commit_nested()
which does exactly what we want, except we are guaranteed that we do not hold
journal transaction open.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Dmitry Monakhov 2013-06-12 22:24:07 -04:00 committed by Theodore Ts'o
parent 981250ca89
commit 9ff8644624
3 changed files with 49 additions and 38 deletions

View File

@ -529,20 +529,17 @@ int jbd2_log_start_commit(journal_t *journal, tid_t tid)
}
/*
* Force and wait upon a commit if the calling process is not within
* transaction. This is used for forcing out undo-protected data which contains
* bitmaps, when the fs is running out of space.
*
* We can only force the running transaction if we don't have an active handle;
* otherwise, we will deadlock.
*
* Returns true if a transaction was started.
* Force and wait any uncommitted transactions. We can only force the running
* transaction if we don't have an active handle, otherwise, we will deadlock.
* Returns: <0 in case of error,
* 0 if nothing to commit,
* 1 if transaction was successfully committed.
*/
int jbd2_journal_force_commit_nested(journal_t *journal)
static int __jbd2_journal_force_commit(journal_t *journal)
{
transaction_t *transaction = NULL;
tid_t tid;
int need_to_start = 0;
int need_to_start = 0, ret = 0;
read_lock(&journal->j_state_lock);
if (journal->j_running_transaction && !current->journal_info) {
@ -553,16 +550,53 @@ int jbd2_journal_force_commit_nested(journal_t *journal)
transaction = journal->j_committing_transaction;
if (!transaction) {
/* Nothing to commit */
read_unlock(&journal->j_state_lock);
return 0; /* Nothing to retry */
return 0;
}
tid = transaction->t_tid;
read_unlock(&journal->j_state_lock);
if (need_to_start)
jbd2_log_start_commit(journal, tid);
jbd2_log_wait_commit(journal, tid);
return 1;
ret = jbd2_log_wait_commit(journal, tid);
if (!ret)
ret = 1;
return ret;
}
/**
* Force and wait upon a commit if the calling process is not within
* transaction. This is used for forcing out undo-protected data which contains
* bitmaps, when the fs is running out of space.
*
* @journal: journal to force
* Returns true if progress was made.
*/
int jbd2_journal_force_commit_nested(journal_t *journal)
{
int ret;
ret = __jbd2_journal_force_commit(journal);
return ret > 0;
}
/**
* int journal_force_commit() - force any uncommitted transactions
* @journal: journal to force
*
* Caller want unconditional commit. We can only force the running transaction
* if we don't have an active handle, otherwise, we will deadlock.
*/
int jbd2_journal_force_commit(journal_t *journal)
{
int ret;
J_ASSERT(!current->journal_info);
ret = __jbd2_journal_force_commit(journal);
if (ret > 0)
ret = 0;
return ret;
}
/*

View File

@ -1661,29 +1661,6 @@ int jbd2_journal_stop(handle_t *handle)
return err;
}
/**
* int jbd2_journal_force_commit() - force any uncommitted transactions
* @journal: journal to force
*
* For synchronous operations: force any uncommitted transactions
* to disk. May seem kludgy, but it reuses all the handle batching
* code in a very simple manner.
*/
int jbd2_journal_force_commit(journal_t *journal)
{
handle_t *handle;
int ret;
handle = jbd2_journal_start(journal, 1);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
} else {
handle->h_sync = 1;
ret = jbd2_journal_stop(handle);
}
return ret;
}
/*
*
* List management code snippets: various functions for manipulating the

View File

@ -1160,6 +1160,7 @@ extern void jbd2_journal_ack_err (journal_t *);
extern int jbd2_journal_clear_err (journal_t *);
extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *);
extern int jbd2_journal_force_commit(journal_t *);
extern int jbd2_journal_force_commit_nested(journal_t *);
extern int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *inode);
extern int jbd2_journal_begin_ordered_truncate(journal_t *journal,
struct jbd2_inode *inode, loff_t new_size);
@ -1235,7 +1236,6 @@ extern void jbd2_clear_buffer_revoked_flags(journal_t *journal);
int jbd2_log_start_commit(journal_t *journal, tid_t tid);
int __jbd2_log_start_commit(journal_t *journal, tid_t tid);
int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
int jbd2_journal_force_commit_nested(journal_t *journal);
int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
int jbd2_complete_transaction(journal_t *journal, tid_t tid);
int jbd2_log_do_checkpoint(journal_t *journal);