linux-stable.git/fs/jbd2, branch v3.16

ext4: disable synchronous transaction batching if max_batch_time==0

2014-07-05T23:18:22+00:00

The mount manpage says of the max_batch_time option,

	This optimization can be turned off entirely
	by setting max_batch_time to 0.

But the code doesn't do that.  So fix the code to do
that.

Signed-off-by: Eric Sandeen 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org

arch: Mass conversion of smp_mb__*()

2014-04-18T12:20:48+00:00

Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra 
Acked-by: Paul E. McKenney 
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds 
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar

jbd2: improve error messages for inconsistent journal heads

2014-03-12T20:38:03+00:00

Fix up error messages printed when the transaction pointers in a
journal head are inconsistent.  This improves the error messages which
are printed when running xfstests generic/068 in data=journal mode.
See the bug report at: https://bugzilla.kernel.org/show_bug.cgi?id=60786

Signed-off-by: "Theodore Ts'o"

jbd2: minimize region locked by j_list_lock in jbd2_journal_forget()

2014-03-09T05:56:58+00:00

It's not needed until we start trying to modifying fields in the
journal_head which are protected by j_list_lock.

Signed-off-by: "Theodore Ts'o"

jbd2: minimize region locked by j_list_lock in journal_get_create_access()

2014-03-09T05:46:23+00:00

It's not needed until we start trying to modifying fields in the
journal_head which are protected by j_list_lock.

Signed-off-by: "Theodore Ts'o"

jbd2: check jh->b_transaction without taking j_list_lock

2014-03-09T05:07:19+00:00

jh->b_transaction is adequately protected for reading by the
jbd_lock_bh_state(bh), so we don't need to take j_list_lock in
__journal_try_to_free_buffer().

Signed-off-by: "Theodore Ts'o"

jbd2: add transaction to checkpoint list earlier

2014-03-09T03:34:10+00:00

We don't otherwise need j_list_lock during the rest of commit phase
#7, so add the transaction to the checkpoint list at the very end of
commit phase #6.  This allows us to drop j_list_lock earlier, which is
a good thing since it is a super hot lock.

Signed-off-by: "Theodore Ts'o"

jbd2: calculate statistics without holding j_state_lock and j_list_lock

2014-03-09T00:51:16+00:00

The two hottest locks, and thus the biggest scalability bottlenecks,
in the jbd2 layer, are the j_list_lock and j_state_lock.  This has
inspired some people to do some truly unnatural things[1].

[1] https://www.usenix.org/system/files/conference/fast14/fast14-paper_kang.pdf

We don't need to be holding both j_state_lock and j_list_lock while
calculating the journal statistics, so move those calculations to the
very end of jbd2_journal_commit_transaction.

Signed-off-by: "Theodore Ts'o"

jbd2: don't hold j_state_lock while calling wake_up()

2014-03-09T00:11:36+00:00

The j_state_lock is one of the hottest locks in the jbd2 layer and
thus one of its scalability bottlenecks.

We don't need to be holding the j_state_lock while we are calling
wake_up(&journal->j_wait_commit), so release the lock a little bit
earlier.

Signed-off-by: "Theodore Ts'o"

jbd2: don't unplug after writing revoke records

2014-03-08T23:13:52+00:00

During commit process, keep the block device plugged after we are done
writing the revoke records, until we are finished writing the rest of
the commit records in the journal.  This will allow most of the
journal blocks to be written in a single I/O operation, instead of
separating the the revoke blocks from the rest of the journal blocks.

Signed-off-by: "Theodore Ts'o"