From cc937db74bd5fe75f4cfebbfc4a04c1da10f0695 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Tue, 27 Jul 2010 11:56:08 -0400 Subject: jbd2: Make barrier messages less scary Saying things like "sync failed" when a device does not support barriers makes users slightly more worried than they need to be; rather than talking about sync failures, let's just state the barrier-based facts. Signed-off-by: Eric Sandeen Signed-off-by: "Theodore Ts'o" --- fs/jbd2/commit.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 75716d3d2be..af056810acb 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -150,8 +150,8 @@ static int journal_submit_commit_record(journal_t *journal, */ if (ret == -EOPNOTSUPP && barrier_done) { printk(KERN_WARNING - "JBD: barrier-based sync failed on %s - " - "disabling barriers\n", journal->j_devname); + "JBD2: Disabling barriers on %s, " + "not supported by device\n", journal->j_devname); spin_lock(&journal->j_state_lock); journal->j_flags &= ~JBD2_BARRIER; spin_unlock(&journal->j_state_lock); @@ -180,8 +180,8 @@ retry: wait_on_buffer(bh); if (buffer_eopnotsupp(bh) && (journal->j_flags & JBD2_BARRIER)) { printk(KERN_WARNING - "JBD2: wait_on_commit_record: sync failed on %s - " - "disabling barriers\n", journal->j_devname); + "JBD2: %s: disabling barries on %s - not supported " + "by device\n", __func__, journal->j_devname); spin_lock(&journal->j_state_lock); journal->j_flags &= ~JBD2_BARRIER; spin_unlock(&journal->j_state_lock); -- cgit v1.2.2 From a51dca9cd3bb4ec5a05bfb6feabf024a5c808a37 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 2 Aug 2010 08:43:25 -0400 Subject: jbd2: Use atomic variables to avoid taking t_handle_lock in jbd2_journal_stop By using an atomic_t for t_updates and t_outstanding credits, this should allow us to not need to take transaction t_handle_lock in jbd2_journal_stop(). Signed-off-by: "Theodore Ts'o" --- fs/jbd2/commit.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index af056810acb..fbd2c564e91 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -417,12 +417,12 @@ void jbd2_journal_commit_transaction(journal_t *journal) stats.run.rs_locked); spin_lock(&commit_transaction->t_handle_lock); - while (commit_transaction->t_updates) { + while (atomic_read(&commit_transaction->t_updates)) { DEFINE_WAIT(wait); prepare_to_wait(&journal->j_wait_updates, &wait, TASK_UNINTERRUPTIBLE); - if (commit_transaction->t_updates) { + if (atomic_read(&commit_transaction->t_updates)) { spin_unlock(&commit_transaction->t_handle_lock); spin_unlock(&journal->j_state_lock); schedule(); @@ -433,7 +433,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) } spin_unlock(&commit_transaction->t_handle_lock); - J_ASSERT (commit_transaction->t_outstanding_credits <= + J_ASSERT (atomic_read(&commit_transaction->t_outstanding_credits) <= journal->j_max_transaction_buffers); /* @@ -527,11 +527,12 @@ void jbd2_journal_commit_transaction(journal_t *journal) stats.run.rs_logging = jiffies; stats.run.rs_flushing = jbd2_time_diff(stats.run.rs_flushing, stats.run.rs_logging); - stats.run.rs_blocks = commit_transaction->t_outstanding_credits; + stats.run.rs_blocks = + atomic_read(&commit_transaction->t_outstanding_credits); stats.run.rs_blocks_logged = 0; J_ASSERT(commit_transaction->t_nr_buffers <= - commit_transaction->t_outstanding_credits); + atomic_read(&commit_transaction->t_outstanding_credits)); err = 0; descriptor = NULL; @@ -616,7 +617,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) * the free space in the log, but this counter is changed * by jbd2_journal_next_log_block() also. */ - commit_transaction->t_outstanding_credits--; + atomic_dec(&commit_transaction->t_outstanding_credits); /* Bump b_count to prevent truncate from stumbling over the shadowed buffer! @@@ This can go if we ever get -- cgit v1.2.2 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/commit.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index fbd2c564e91..67bb0a2f35e 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -152,9 +152,9 @@ static int journal_submit_commit_record(journal_t *journal, printk(KERN_WARNING "JBD2: Disabling barriers on %s, " "not supported by device\n", journal->j_devname); - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); journal->j_flags &= ~JBD2_BARRIER; - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); /* And try again, without the barrier */ lock_buffer(bh); @@ -182,9 +182,9 @@ retry: printk(KERN_WARNING "JBD2: %s: disabling barries on %s - not supported " "by device\n", __func__, journal->j_devname); - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); journal->j_flags &= ~JBD2_BARRIER; - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); lock_buffer(bh); clear_buffer_dirty(bh); @@ -400,7 +400,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) jbd_debug(1, "JBD: starting commit of transaction %d\n", commit_transaction->t_tid); - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); commit_transaction->t_state = T_LOCKED; /* @@ -424,9 +424,9 @@ void jbd2_journal_commit_transaction(journal_t *journal) TASK_UNINTERRUPTIBLE); if (atomic_read(&commit_transaction->t_updates)) { spin_unlock(&commit_transaction->t_handle_lock); - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); schedule(); - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); spin_lock(&commit_transaction->t_handle_lock); } finish_wait(&journal->j_wait_updates, &wait); @@ -497,7 +497,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) start_time = ktime_get(); commit_transaction->t_log_start = journal->j_head; wake_up(&journal->j_wait_transaction_locked); - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); jbd_debug (3, "JBD: commit phase 2\n"); @@ -519,9 +519,9 @@ void jbd2_journal_commit_transaction(journal_t *journal) * transaction! Now comes the tricky part: we need to write out * metadata. Loop over the transaction's entire buffer list: */ - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); commit_transaction->t_state = T_COMMIT; - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); trace_jbd2_commit_logging(journal, commit_transaction); stats.run.rs_logging = jiffies; @@ -978,7 +978,7 @@ restart_loop: * __jbd2_journal_drop_transaction(). Otherwise we could race with * other checkpointing code processing the transaction... */ - spin_lock(&journal->j_state_lock); + write_lock(&journal->j_state_lock); spin_lock(&journal->j_list_lock); /* * Now recheck if some buffers did not get attached to the transaction @@ -986,7 +986,7 @@ restart_loop: */ if (commit_transaction->t_forget) { spin_unlock(&journal->j_list_lock); - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); goto restart_loop; } @@ -1038,7 +1038,7 @@ restart_loop: journal->j_average_commit_time*3) / 4; else journal->j_average_commit_time = commit_time; - spin_unlock(&journal->j_state_lock); + write_unlock(&journal->j_state_lock); if (commit_transaction->t_checkpoint_list == NULL && commit_transaction->t_checkpoint_io_list == NULL) { -- cgit v1.2.2 From 8dd420466c7bfc459fa04680bd5690bfc41a4553 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 3 Aug 2010 21:38:29 -0400 Subject: jbd2: Remove t_handle_lock from start_this_handle() This should remove the last exclusive lock from start_this_handle(), so that we should now be able to start multiple transactions at the same time on large SMP systems. Signed-off-by: "Theodore Ts'o" --- fs/jbd2/commit.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 67bb0a2f35e..f52e5e8049f 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -1004,7 +1004,8 @@ restart_loop: * File the transaction statistics */ stats.ts_tid = commit_transaction->t_tid; - stats.run.rs_handle_count = commit_transaction->t_handle_count; + stats.run.rs_handle_count = + atomic_read(&commit_transaction->t_handle_count); trace_jbd2_run_stats(journal->j_fs_dev->bd_dev, commit_transaction->t_tid, &stats.run); -- cgit v1.2.2 From 87e99511ea54510ffb60b98001d108794d5037f8 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 11 Aug 2010 17:05:45 +0200 Subject: kill BH_Ordered flag Instead of abusing a buffer_head flag just add a variant of sync_dirty_buffer which allows passing the exact type of write flag required. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- fs/jbd2/commit.c | 39 +++++++++++++++------------------------ 1 file changed, 15 insertions(+), 24 deletions(-) (limited to 'fs/jbd2/commit.c') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index f52e5e8049f..7c068c189d8 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -101,7 +101,6 @@ static int journal_submit_commit_record(journal_t *journal, struct commit_header *tmp; struct buffer_head *bh; int ret; - int barrier_done = 0; struct timespec now = current_kernel_time(); if (is_journal_aborted(journal)) @@ -136,30 +135,22 @@ static int journal_submit_commit_record(journal_t *journal, if (journal->j_flags & JBD2_BARRIER && !JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) { - set_buffer_ordered(bh); - barrier_done = 1; - } - ret = submit_bh(WRITE_SYNC_PLUG, bh); - if (barrier_done) - clear_buffer_ordered(bh); - - /* is it possible for another commit to fail at roughly - * the same time as this one? If so, we don't want to - * trust the barrier flag in the super, but instead want - * to remember if we sent a barrier request - */ - if (ret == -EOPNOTSUPP && barrier_done) { - printk(KERN_WARNING - "JBD2: Disabling barriers on %s, " - "not supported by device\n", journal->j_devname); - write_lock(&journal->j_state_lock); - journal->j_flags &= ~JBD2_BARRIER; - write_unlock(&journal->j_state_lock); + ret = submit_bh(WRITE_SYNC_PLUG | WRITE_BARRIER, bh); + if (ret == -EOPNOTSUPP) { + printk(KERN_WARNING + "JBD2: Disabling barriers on %s, " + "not supported by device\n", journal->j_devname); + write_lock(&journal->j_state_lock); + journal->j_flags &= ~JBD2_BARRIER; + write_unlock(&journal->j_state_lock); - /* And try again, without the barrier */ - lock_buffer(bh); - set_buffer_uptodate(bh); - clear_buffer_dirty(bh); + /* And try again, without the barrier */ + lock_buffer(bh); + set_buffer_uptodate(bh); + clear_buffer_dirty(bh); + ret = submit_bh(WRITE_SYNC_PLUG, bh); + } + } else { ret = submit_bh(WRITE_SYNC_PLUG, bh); } *cbh = bh; -- cgit v1.2.2