Darrick J. Wong ffecfd1a72 block: optionally snapshot page contents to provide stable pages during write ... This provides a band-aid to provide stable page writes on jbd without needing to backport the fixed locking and page writeback bit handling schemes of jbd2. The band-aid works by using bounce buffers to snapshot page contents instead of waiting. For those wondering about the ext3 bandage -- fixing the jbd locking (which was done as part of ext4dev years ago) is a lot of surgery, and setting PG_writeback on data pages when we actually hold the page lock dropped ext3 performance by nearly an order of magnitude. If we're going to migrate iscsi and raid to use stable page writes, the complaints about high latency will likely return. We might as well centralize their page snapshotting thing to one place. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Tested-by: Andy Lutomirski <luto@amacapital.net> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Artem Bityutskiy <dedekind1@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2013-02-21 17:22:20 -08:00
..
partitions	Merge branch 'for-3.8/drivers' of git://git.kernel.dk/linux-block	2012-12-17 13:39:11 -08:00
blk-cgroup.c	Merge branch 'for-3.8/core' of git://git.kernel.dk/linux-block	2012-12-17 08:27:23 -08:00
blk-cgroup.h
blk-core.c	block: optionally snapshot page contents to provide stable pages during write	2013-02-21 17:22:20 -08:00
blk-exec.c	sched: Move sched.h sysctl bits into separate header	2013-02-07 20:50:54 +01:00
blk-flush.c
blk-integrity.c	bdi: allow block devices to say that they require stable page writes	2013-02-21 17:22:19 -08:00
blk-ioc.c
blk-iopoll.c
blk-lib.c	block: add plug for blkdev_issue_discard	2012-12-14 20:46:04 +01:00
blk-map.c
blk-merge.c
blk-settings.c	block: discard granularity might not be power of 2	2012-12-14 20:46:04 +01:00
blk-softirq.c
blk-sysfs.c
blk-tag.c
blk-throttle.c
blk-timeout.c
blk.h
bsg-lib.c
bsg.c
cfq-iosched.c
compat_ioctl.c
deadline-iosched.c	deadline: Allow 0ms deadline latency, increase the read speed	2012-12-09 19:19:23 +01:00
elevator.c	block: don't request module during elevator init	2013-01-22 16:48:03 -08:00
genhd.c	block: prevent race/cleanup	2012-12-19 20:36:10 +01:00
ioctl.c
Kconfig	percpu_rw_semaphore: introduce CONFIG_PERCPU_RWSEM	2012-12-17 17:15:18 -08:00
Kconfig.iosched
Makefile
noop-iosched.c
partition-generic.c
scsi_ioctl.c