From a931da6ac9331a6c80dd91c199105806f2336188 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 3 Aug 2010 21:35:12 -0400 Subject: jbd2: Change j_state_lock to be a rwlock_t Lockstat reports have shown that j_state_lock is a major source of lock contention, especially on systems with more than 4 CPU cores. So change it to be a read/write spinlock. Signed-off-by: "Theodore Ts'o" --- fs/jbd2/checkpoint.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'fs/jbd2/checkpoint.c') diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c index f8cdc02..1c23a0f 100644 --- a/fs/jbd2/checkpoint.c +++ b/fs/jbd2/checkpoint.c @@ -118,13 +118,13 @@ static int __try_to_free_cp_buf(struct journal_head *jh) void __jbd2_log_wait_for_space(journal_t *journal) { int nblocks, space_left; - assert_spin_locked(&journal->j_state_lock); + /* assert_spin_locked(&journal->j_state_lock); */ nblocks = jbd_space_needed(journal); while (__jbd2_log_space_left(journal) < nblocks) { if (journal->j_flags & JBD2_ABORT) return; - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); mutex_lock(&journal->j_checkpoint_mutex); /* @@ -138,7 +138,7 @@ void __jbd2_log_wait_for_space(journal_t *journal) * filesystem, so abort the journal and leave a stack * trace for forensic evidence. */ - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); spin_lock(&journal->j_list_lock); nblocks = jbd_space_needed(journal); space_left = __jbd2_log_space_left(journal); @@ -149,7 +149,7 @@ void __jbd2_log_wait_for_space(journal_t *journal) if (journal->j_committing_transaction) tid = journal->j_committing_transaction->t_tid; spin_unlock(&journal->j_list_lock); - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); if (chkpt) { jbd2_log_do_checkpoint(journal); } else if (jbd2_cleanup_journal_tail(journal) == 0) { @@ -167,7 +167,7 @@ void __jbd2_log_wait_for_space(journal_t *journal) WARN_ON(1); jbd2_journal_abort(journal, 0); } - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); } else { spin_unlock(&journal->j_list_lock); } @@ -474,7 +474,7 @@ int jbd2_cleanup_journal_tail(journal_t *journal) * next transaction ID we will write, and where it will * start. */ - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); spin_lock(&journal->j_list_lock); transaction = journal->j_checkpoint_transactions; if (transaction) { @@ -496,7 +496,7 @@ int jbd2_cleanup_journal_tail(journal_t *journal) /* If the oldest pinned transaction is at the tail of the log already then there's not much we can do right now. */ if (journal->j_tail_sequence == first_tid) { - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); return 1; } @@ -516,7 +516,7 @@ int jbd2_cleanup_journal_tail(journal_t *journal) journal->j_free += freed; journal->j_tail_sequence = first_tid; journal->j_tail = blocknr; - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); /* * If there is an external journal, we need to make sure that -- cgit v1.1