From 9ff864462477206bc23b405a6ae506e92fb6dc9c Mon Sep 17 00:00:00 2001 From: Dmitry Monakhov Date: Wed, 12 Jun 2013 22:24:07 -0400 Subject: [PATCH] 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 Signed-off-by: "Theodore Ts'o" --- fs/jbd2/journal.c | 62 +++++++++++++++++++++++++++++++++++++++------------ fs/jbd2/transaction.c | 23 ------------------- include/linux/jbd2.h | 2 +- 3 files changed, 49 insertions(+), 38 deletions(-) diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 70990d6..0e6c13b 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -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; } /* diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index f33342a..dd422e6 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -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 diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index fb91c8d..c3645b9 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -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); -- 2.7.4