Commit Graph

253139 Commits

Author SHA1 Message Date
Wu Fengguang
d46db3d582 writeback: make writeback_control.nr_to_write straight
Pass struct wb_writeback_work all the way down to writeback_sb_inodes(),
and initialize the struct writeback_control there.

struct writeback_control is basically designed to control writeback of a
single file, but we keep abuse it for writing multiple files in
writeback_sb_inodes() and its callers.

It immediately clean things up, e.g. suddenly wbc.nr_to_write vs
work->nr_pages starts to make sense, and instead of saving and restoring
pages_skipped in writeback_sb_inodes it can always start with a clean
zero value.

It also makes a neat IO pattern change: large dirty files are now
written in the full 4MB writeback chunk size, rather than whatever
remained quota in wbc->nr_to_write.

Acked-by: Jan Kara <jack@suse.cz>
Proposed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-07-09 22:09:01 -07:00
Wu Fengguang
36715cef07 writeback: skip tmpfs early in balance_dirty_pages_ratelimited_nr()
This helps prevent tmpfs dirtiers from skewing the per-cpu bdp_ratelimits.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-20 00:25:46 +08:00
Wu Fengguang
e84d0a4f8e writeback: trace event writeback_queue_io
Note that it adds a little overheads to account the moved/enqueued
inodes from b_dirty to b_io. The "moved" accounting may be later used to
limit the number of inodes that can be moved in one shot, in order to
keep spinlock hold time under control.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Wu Fengguang
251d6a471c writeback: trace event writeback_single_inode
It is valuable to know how the dirty inodes are iterated and their IO size.

"writeback_single_inode: bdi 8:0: ino=134246746 state=I_DIRTY_SYNC|I_SYNC age=414 index=0 to_write=1024 wrote=0"

- "state" reflects inode->i_state at the end of writeback_single_inode()
- "index" reflects mapping->writeback_index after the ->writepages() call
- "to_write" is the wbc->nr_to_write at entrance of writeback_single_inode()
- "wrote" is the number of pages actually written

v2: add trace event writeback_single_inode_requeue as proposed by Dave.

CC: Dave Chinner <david@fromorbit.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Wu Fengguang
846d5a091b writeback: remove .nonblocking and .encountered_congestion
Remove two unused struct writeback_control fields:

	.encountered_congestion	(completely unused)
	.nonblocking		(never set, checked/showed in XFS,NFS/btrfs)

The .for_background check in nfs_write_inode() is also removed btw,
as .for_background implies WB_SYNC_NONE.

Reviewed-by: Jan Kara <jack@suse.cz>
Proposed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Wu Fengguang
b7a2441f99 writeback: remove writeback_control.more_io
When wbc.more_io was first introduced, it indicates whether there are
at least one superblock whose s_more_io contains more IO work. Now with
the per-bdi writeback, it can be replaced with a simple b_more_io test.

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Wu Fengguang
3efaf0faba writeback: skip balance_dirty_pages() for in-memory fs
This avoids unnecessary checks and dirty throttling on tmpfs/ramfs.

Notes about the tmpfs/ramfs behavior changes:

As for 2.6.36 and older kernels, the tmpfs writes will sleep inside
balance_dirty_pages() as long as we are over the (dirty+background)/2
global throttle threshold.  This is because both the dirty pages and
threshold will be 0 for tmpfs/ramfs. Hence this test will always
evaluate to TRUE:

                dirty_exceeded =
                        (bdi_nr_reclaimable + bdi_nr_writeback >= bdi_thresh)
                        || (nr_reclaimable + nr_writeback >= dirty_thresh);

For 2.6.37, someone complained that the current logic does not allow the
users to set vm.dirty_ratio=0.  So commit 4cbec4c8b9 changed the test to

                dirty_exceeded =
                        (bdi_nr_reclaimable + bdi_nr_writeback > bdi_thresh)
                        || (nr_reclaimable + nr_writeback > dirty_thresh);

So 2.6.37 will behave differently for tmpfs/ramfs: it will never get
throttled unless the global dirty threshold is exceeded (which is very
unlikely to happen; once happen, will block many tasks).

I'd say that the 2.6.36 behavior is very bad for tmpfs/ramfs. It means
for a busy writing server, tmpfs write()s may get livelocked! The
"inadvertent" throttling can hardly bring help to any workload because
of its "either no throttling, or get throttled to death" property.

So based on 2.6.37, this patch won't bring more noticeable changes.

CC: Hugh Dickins <hughd@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:22 +08:00
Wu Fengguang
6f71865627 writeback: add bdi_dirty_limit() kernel-doc
Clarify the bdi_dirty_limit() comment.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:22 +08:00
Wu Fengguang
e185dda89d writeback: avoid extra sync work at enqueue time
This removes writeback_control.wb_start and does more straightforward
sync livelock prevention by setting .older_than_this to prevent extra
inodes from being enqueued in the first place.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:22 +08:00
Wu Fengguang
e8dfc30582 writeback: elevate queue_io() into wb_writeback()
Code refactor for more logical code layout.
No behavior change.

- remove the mis-named __writeback_inodes_sb()

- wb_writeback()/writeback_inodes_wb() will decide when to queue_io()
  before calling __writeback_inodes_wb()

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:21 +08:00
Christoph Hellwig
f758eeabeb writeback: split inode_wb_list_lock into bdi_writeback.list_lock
Split the global inode_wb_list_lock into a per-bdi_writeback list_lock,
as it's currently the most contended lock in the system for metadata
heavy workloads.  It won't help for single-filesystem workloads for
which we'll need the I/O-less balance_dirty_pages, but at least we
can dedicate a cpu to spinning on each bdi now for larger systems.

Based on earlier patches from Nick Piggin and Dave Chinner.

It reduces lock contentions to 1/4 in this test case:
10 HDD JBOD, 100 dd on each disk, XFS, 6GB ram

lock_stat version 0.3
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                              class name    con-bounces    contentions   waittime-min   waittime-max waittime-total    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
vanilla 2.6.39-rc3:
                      inode_wb_list_lock:         42590          44433           0.12         147.74      144127.35         252274         886792           0.08         121.34      917211.23
                      ------------------
                      inode_wb_list_lock              2          [<ffffffff81165da5>] bdev_inode_switch_bdi+0x29/0x85
                      inode_wb_list_lock             34          [<ffffffff8115bd0b>] inode_wb_list_del+0x22/0x49
                      inode_wb_list_lock          12893          [<ffffffff8115bb53>] __mark_inode_dirty+0x170/0x1d0
                      inode_wb_list_lock          10702          [<ffffffff8115afef>] writeback_single_inode+0x16d/0x20a
                      ------------------
                      inode_wb_list_lock              2          [<ffffffff81165da5>] bdev_inode_switch_bdi+0x29/0x85
                      inode_wb_list_lock             19          [<ffffffff8115bd0b>] inode_wb_list_del+0x22/0x49
                      inode_wb_list_lock           5550          [<ffffffff8115bb53>] __mark_inode_dirty+0x170/0x1d0
                      inode_wb_list_lock           8511          [<ffffffff8115b4ad>] writeback_sb_inodes+0x10f/0x157

2.6.39-rc3 + patch:
                &(&wb->list_lock)->rlock:         11383          11657           0.14         151.69       40429.51          90825         527918           0.11         145.90      556843.37
                ------------------------
                &(&wb->list_lock)->rlock             10          [<ffffffff8115b189>] inode_wb_list_del+0x5f/0x86
                &(&wb->list_lock)->rlock           1493          [<ffffffff8115b1ed>] writeback_inodes_wb+0x3d/0x150
                &(&wb->list_lock)->rlock           3652          [<ffffffff8115a8e9>] writeback_sb_inodes+0x123/0x16f
                &(&wb->list_lock)->rlock           1412          [<ffffffff8115a38e>] writeback_single_inode+0x17f/0x223
                ------------------------
                &(&wb->list_lock)->rlock              3          [<ffffffff8110b5af>] bdi_lock_two+0x46/0x4b
                &(&wb->list_lock)->rlock              6          [<ffffffff8115b189>] inode_wb_list_del+0x5f/0x86
                &(&wb->list_lock)->rlock           2061          [<ffffffff8115af97>] __mark_inode_dirty+0x173/0x1cf
                &(&wb->list_lock)->rlock           2629          [<ffffffff8115a8e9>] writeback_sb_inodes+0x123/0x16f

hughd@google.com: fix recursive lock when bdi_lock_two() is called with new the same as old
akpm@linux-foundation.org: cleanup bdev_inode_switch_bdi() comment

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:21 +08:00
Wu Fengguang
424b351fe1 writeback: refill b_io iff empty
There is no point to carry different refill policies between for_kupdate
and other type of works. Use a consistent "refill b_io iff empty" policy
which can guarantee fairness in an easy to understand way.

A b_io refill will setup a _fixed_ work set with all currently eligible
inodes and start a new round of walk through b_io. The "fixed" work set
means no new inodes will be added to the work set during the walk.
Only when a complete walk over b_io is done, new inodes that are
eligible at the time will be enqueued and the walk be started over.

This procedure provides fairness among the inodes because it guarantees
each inode to be synced once and only once at each round. So all inodes
will be free from starvations.

This change relies on wb_writeback() to keep retrying as long as we made
some progress on cleaning some pages and/or inodes. Without that ability,
the old logic on background works relies on aggressively queuing all
eligible inodes into b_io at every time. But that's not a guarantee.

The below test script completes a slightly faster now:

             2.6.39-rc3	  2.6.39-rc3-dyn-expire+
------------------------------------------------
all elapsed     256.043      252.367
stddev           24.381       12.530

tar elapsed      30.097       28.808
dd  elapsed      13.214       11.782

	#!/bin/zsh

	cp /c/linux-2.6.38.3.tar.bz2 /dev/shm/

	umount /dev/sda7
	mkfs.xfs -f /dev/sda7
	mount /dev/sda7 /fs

	echo 3 > /proc/sys/vm/drop_caches

	tic=$(cat /proc/uptime|cut -d' ' -f2)

	cd /fs
	time tar jxf /dev/shm/linux-2.6.38.3.tar.bz2 &
	time dd if=/dev/zero of=/fs/zero bs=1M count=1000 &

	wait
	sync
	tac=$(cat /proc/uptime|cut -d' ' -f2)
	echo elapsed: $((tac - tic))

It maintains roughly the same small vs. large file writeout shares, and
offers large files better chances to be written in nice 4M chunks.

Analyzes from Dave Chinner in great details:

Let's say we have lots of inodes with 100 dirty pages being created,
and one large writeback going on. We expire 8 new inodes for every
1024 pages we write back.

With the old code, we do:

	b_more_io (large inode) -> b_io (1l)
	8 newly expired inodes -> b_io (1l, 8s)

	writeback  large inode 1024 pages -> b_more_io

	b_more_io (large inode) -> b_io (8s, 1l)
	8 newly expired inodes -> b_io (8s, 1l, 8s)

	writeback  8 small inodes 800 pages
		   1 large inode 224 pages -> b_more_io

	b_more_io (large inode) -> b_io (8s, 1l)
	8 newly expired inodes -> b_io (8s, 1l, 8s)
	.....

Your new code:

	b_more_io (large inode) -> b_io (1l)
	8 newly expired inodes -> b_io (1l, 8s)

	writeback  large inode 1024 pages -> b_more_io
	(b_io == 8s)
	writeback  8 small inodes 800 pages

	b_io empty: (1800 pages written)
		b_more_io (large inode) -> b_io (1l)
		14 newly expired inodes -> b_io (1l, 14s)

	writeback  large inode 1024 pages -> b_more_io
	(b_io == 14s)
	writeback  10 small inodes 1000 pages
		   1 small inode 24 pages -> b_more_io (1l, 1s(24))
	writeback  5 small inodes 500 pages
	b_io empty: (2548 pages written)
		b_more_io (large inode) -> b_io (1l, 1s(24))
		20 newly expired inodes -> b_io (1l, 1s(24), 20s)
	......

Rough progression of pages written at b_io refill:

Old code:

	total	large file	% of writeback
	1024	224		21.9% (fixed)

New code:
	total	large file	% of writeback
	1800	1024		~55%
	2550	1024		~40%
	3050	1024		~33%
	3500	1024		~29%
	3950	1024		~26%
	4250	1024		~24%
	4500	1024		~22.7%
	4700	1024		~21.7%
	4800	1024		~21.3%
	4800	1024		~21.3%
	(pretty much steady state from here)

Ok, so the steady state is reached with a similar percentage of
writeback to the large file as the existing code. Ok, that's good,
but providing some evidence that is doesn't change the shared of
writeback to the large should be in the commit message ;)

The other advantage to this is that we always write 1024 page chunks
to the large file, rather than smaller "whatever remains" chunks.

CC: Jan Kara <jack@suse.cz>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:21 +08:00
Wu Fengguang
ba9aa8399f writeback: the kupdate expire timestamp should be a moving target
Dynamically compute the dirty expire timestamp at queue_io() time.

writeback_control.older_than_this used to be determined at entrance to
the kupdate writeback work. This _static_ timestamp may go stale if the
kupdate work runs on and on. The flusher may then stuck with some old
busy inodes, never considering newly expired inodes thereafter.

This has two possible problems:

- It is unfair for a large dirty inode to delay (for a long time) the
  writeback of small dirty inodes.

- As time goes by, the large and busy dirty inode may contain only
  _freshly_ dirtied pages. Ignoring newly expired dirty inodes risks
  delaying the expired dirty pages to the end of LRU lists, triggering
  the evil pageout(). Nevertheless this patch merely addresses part
  of the problem.

v2: keep policy changes inside wb_writeback() and keep the
wbc.older_than_this visibility as suggested by Dave.

CC: Dave Chinner <david@fromorbit.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Itaru Kitayama <kitayama@cl.bb4u.ne.jp>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:21 +08:00
Wu Fengguang
e6fb6da2e1 writeback: try more writeback as long as something was written
writeback_inodes_wb()/__writeback_inodes_sb() are not aggressive in that
they only populate possibly a subset of eligible inodes into b_io at
entrance time. When the queued set of inodes are all synced, they just
return, possibly with all queued inode pages written but still
wbc.nr_to_write > 0.

For kupdate and background writeback, there may be more eligible inodes
sitting in b_dirty when the current set of b_io inodes are completed. So
it is necessary to try another round of writeback as long as we made some
progress in this round. When there are no more eligible inodes, no more
inodes will be enqueued in queue_io(), hence nothing could/will be
synced and we may safely bail.

For example, imagine 100 inodes

        i0, i1, i2, ..., i90, i91, i99

At queue_io() time, i90-i99 happen to be expired and moved to s_io for
IO. When finished successfully, if their total size is less than
MAX_WRITEBACK_PAGES, nr_to_write will be > 0. Then wb_writeback() will
quit the background work (w/o this patch) while it's still over
background threshold. This will be a fairly normal/frequent case I guess.

Now that we do tagged sync and update inode->dirtied_when after the sync,
this change won't livelock sync(1).  I actually tried to write 1 page
per 1ms with this command

	write-and-fsync -n10000 -S 1000 -c 4096 /fs/test

and do sync(1) at the same time. The sync completes quickly on ext4,
xfs, btrfs.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:20 +08:00
Wu Fengguang
cb9bd1159c writeback: introduce writeback_control.inodes_written
The flusher works on dirty inodes in batches, and may quit prematurely
if the batch of inodes happen to be metadata-only dirtied: in this case
wbc->nr_to_write won't be decreased at all, which stands for "no pages
written" but also mis-interpreted as "no progress".

So introduce writeback_control.inodes_written to count the inodes get
cleaned from VFS POV.  A non-zero value means there are some progress on
writeback, in which case more writeback can be tried.

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:20 +08:00
Wu Fengguang
94c3dcbb0b writeback: update dirtied_when for synced inode to prevent livelock
Explicitly update .dirtied_when on synced inodes, so that they are no
longer considered for writeback in the next round.

It can prevent both of the following livelock schemes:

- while true; do echo data >> f; done
- while true; do touch f;        done (in theory)

The exact livelock condition is, during sync(1):

(1) no new inodes are dirtied
(2) an inode being actively dirtied

On (2), the inode will be tagged and synced with .nr_to_write=LONG_MAX.
When finished, it will be redirty_tail()ed because it's still dirty
and (.nr_to_write > 0). redirty_tail() won't update its ->dirtied_when
on condition (1). The sync work will then revisit it on the next
queue_io() and find it eligible again because its old ->dirtied_when
predates the sync work start time.

We'll do more aggressive "keep writeback as long as we wrote something"
logic in wb_writeback(). The "use LONG_MAX .nr_to_write" trick in commit
b9543dac5b ("writeback: avoid livelocking WB_SYNC_ALL writeback") will
no longer be enough to stop sync livelock.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:20 +08:00
Wu Fengguang
6e6938b6d3 writeback: introduce .tagged_writepages for the WB_SYNC_NONE sync stage
sync(2) is performed in two stages: the WB_SYNC_NONE sync and the
WB_SYNC_ALL sync. Identify the first stage with .tagged_writepages and
do livelock prevention for it, too.

Jan's commit f446daaea9 ("mm: implement writeback livelock avoidance
using page tagging") is a partial fix in that it only fixed the
WB_SYNC_ALL phase livelock.

Although ext4 is tested to no longer livelock with commit f446daaea9,
it may due to some "redirty_tail() after pages_skipped" effect which
is by no means a guarantee for _all_ the file systems.

Note that writeback_inodes_sb() is called by not only sync(), they are
treated the same because the other callers also need livelock prevention.

Impact:  It changes the order in which pages/inodes are synced to disk.
Now in the WB_SYNC_NONE stage, it won't proceed to write the next inode
until finished with the current inode.

Acked-by: Jan Kara <jack@suse.cz>
CC: Dave Chinner <david@fromorbit.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:20 +08:00
Linus Torvalds
59c5f46fbe Linux 3.0-rc2 2011-06-06 18:06:33 +09:00
Hugh Dickins
e0dcd8a05b mm: fix ENOSPC returned by handle_mm_fault()
Al Viro observes that in the hugetlb case, handle_mm_fault() may return
a value of the kind ENOSPC when its caller is expecting a value of the
kind VM_FAULT_SIGBUS: fix alloc_huge_page()'s failure returns.

Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-06 18:00:27 +09:00
Linus Torvalds
0d6925d43b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ALSA: usb - turn off de-emphasis in s/pdif for cm6206
  ALSA: asihpi: Use angle brackets for system includes
  ALSA: fm801: add error handling if auto-detect fails
  ALSA: hda - Check pin support EAPD in ad198x_power_eapd_write
  ALSA: hda - Fix HP and Front pins of ad1988/ad1989 in ad198x_power_eapd()
  ALSA: 6fire: Don't leak firmware in error path
  ASoC: Fix wm_hubs input PGA ZC bits
  ASoC: Fix dapm_is_shared_kcontrol so everything isn't shared
2011-06-06 17:51:28 +09:00
Linus Torvalds
c12f667e75 Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging:
  hwmon: (max6642): Better chip detection schema
  hwmon: (coretemp) Further relax temperature range checks
  hwmon: (coretemp) Fix TjMax detection for older CPUs
  hwmon: (coretemp) Relax target temperature range check
  hwmon: (max6642) Rename temp_fault sysfs attribute to temp2_fault
2011-06-06 17:48:02 +09:00
Takashi Iwai
3190dad97b Merge branch 'fix/asoc' into for-linus 2011-06-06 09:28:49 +02:00
Linus Torvalds
0792644d22 Merge branch 'for-linus' of git://android.git.kernel.org/kernel/tegra
* 'for-linus' of git://android.git.kernel.org/kernel/tegra:
  ARM: Tegra: Harmony: Fix conflicting GPIO numbering
2011-06-05 08:11:11 +09:00
Stephen Warren
f2a4d8ae4d ARM: Tegra: Harmony: Fix conflicting GPIO numbering
Currently, both the WM8903 and TPS6586x chips attempt to register with
gpiolib using the same GPIO numbers. This causes the audio driver to
fail to initialize.

To solve this, add a define to board-harmony.h for the TPS6586x, and make
board-harmony-power.c use this define, instead of directly referencing
TEGRA_NR_GPIOS.

This fixes a regression introduced by commit
6f168f2fa6.
ARM: tegra: harmony: initialize the TPS65862 PMIC

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Colin Cross <ccross@android.com>
2011-06-04 15:51:52 -07:00
Linus Torvalds
e6ece70732 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (25 commits)
  btrfs: fix uninitialized variable warning
  btrfs: add helper for fs_info->closing
  Btrfs: add mount -o inode_cache
  btrfs: scrub: add explicit plugging
  btrfs: use btrfs_ino to access inode number
  Btrfs: don't save the inode cache if we are deleting this root
  btrfs: false BUG_ON when degraded
  Btrfs: don't save the inode cache in non-FS roots
  Btrfs: make sure we don't overflow the free space cache crc page
  Btrfs: fix uninit variable in the delayed inode code
  btrfs: scrub: don't reuse bios and pages
  Btrfs: leave spinning on lookup and map the leaf
  Btrfs: check for duplicate entries in the free space cache
  Btrfs: don't try to allocate from a block group that doesn't have enough space
  Btrfs: don't always do readahead
  Btrfs: try not to sleep as much when doing slow caching
  Btrfs: kill BTRFS_I(inode)->block_group
  Btrfs: don't look at the extent buffer level 3 times in a row
  Btrfs: map the node block when looking for readahead targets
  Btrfs: set range_start to the right start in count_range_bits
  ...
2011-06-05 06:17:23 +09:00
Per Dalén
942c1a927b hwmon: (max6642): Better chip detection schema
Improve detection of MAX6642 by reading non existing registers (0x04, 0x06
and 0xff). Reading those registers returns the previously read value.

Signed-off-by: Per Dalen <per.dalen@appeartv.com>
[guenter.roeck@ericsson.com: added second set of register reads]
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
2011-06-04 10:34:28 -07:00
Linus Torvalds
23c79d31a3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] Fix oops caused by queue refcounting failure
2011-06-04 23:19:51 +09:00
Linus Torvalds
0e833d8cfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (40 commits)
  tg3: Fix tg3_skb_error_unmap()
  net: tracepoint of net_dev_xmit sees freed skb and causes panic
  drivers/net/can/flexcan.c: add missing clk_put
  net: dm9000: Get the chip in a known good state before enabling interrupts
  drivers/net/davinci_emac.c: add missing clk_put
  af-packet: Add flag to distinguish VID 0 from no-vlan.
  caif: Fix race when conditionally taking rtnl lock
  usbnet/cdc_ncm: add missing .reset_resume hook
  vlan: fix typo in vlan_dev_hard_start_xmit()
  net/ipv4: Check for mistakenly passed in non-IPv4 address
  iwl4965: correctly validate temperature value
  bluetooth l2cap: fix locking in l2cap_global_chan_by_psm
  ath9k: fix two more bugs in tx power
  cfg80211: don't drop p2p probe responses
  Revert "net: fix section mismatches"
  drivers/net/usb/catc.c: Fix potential deadlock in catc_ctrl_run()
  sctp: stop pending timers and purge queues when peer restart asoc
  drivers/net: ks8842 Fix crash on received packet when in PIO mode.
  ip_options_compile: properly handle unaligned pointer
  iwlagn: fix incorrect PCI subsystem id for 6150 devices
  ...
2011-06-04 23:16:00 +09:00
David Sterba
aa0467d8d2 btrfs: fix uninitialized variable warning
With Linus' tree, today's linux-next build (powercp ppc64_defconfig)
produced this warning:

fs/btrfs/delayed-inode.c: In function 'btrfs_delayed_update_inode':
fs/btrfs/delayed-inode.c:1598:6: warning: 'ret' may be used
uninitialized in this function

Introduced by commit 16cdcec736 ("btrfs: implement delayed inode items
operation").

This fixes a bug in btrfs_update_inode(): if the returned value from
btrfs_delayed_update_inode is a nonzero garbage, inode stat data are not
updated and several call paths may hit a BUG_ON or fail with strange
code.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David Sterba <dsterba@suse.cz>
2011-06-04 08:11:38 -04:00
David Sterba
7841cb2898 btrfs: add helper for fs_info->closing
wrap checking of filesystem 'closing' flag and fix a few missing memory
barriers.

Signed-off-by: David Sterba <dsterba@suse.cz>
2011-06-04 08:11:22 -04:00
Chris Mason
4b9465cb9e Btrfs: add mount -o inode_cache
This makes the inode map cache default to off until we
fix the overflow problem when the free space crcs don't fit
inside a single page.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:47 -04:00
Arne Jansen
e7786c3ae5 btrfs: scrub: add explicit plugging
With the removal of the implicit plugging scrub ends up doing more and
smaller I/O than necessary. This patch adds explicit plugging per chunk.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:46 -04:00
David Sterba
a4689d2bd3 btrfs: use btrfs_ino to access inode number
commit 4cb5300bc ("Btrfs: add mount -o auto_defrag") accesses inode
number directly while it should use the helper with the new inode
number allocator.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:46 -04:00
Josef Bacik
d132a538d2 Btrfs: don't save the inode cache if we are deleting this root
With xfstest 254 I can panic the box every time with the inode number caching
stuff on.  This is because we clean the inodes out when we delete the subvolume,
but then we write out the inode cache which adds an inode to the subvolume inode
tree, and then when it gets evicted again the root gets added back on the dead
roots list and is deleted again, so we have a double free.  To stop this from
happening just return 0 if refs is 0 (and we're not the tree root since tree
root always has refs of 0).  With this fix 254 no longer panics.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:45 -04:00
Arne Jansen
5f3f302a6f btrfs: false BUG_ON when degraded
In degraded mode the struct btrfs_device of missing devs don't have
device->name set. A kstrdup of NULL correctly returns NULL. Don't
BUG in this case.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:44 -04:00
liubo
ca456ae280 Btrfs: don't save the inode cache in non-FS roots
This adds extra checks to make sure the inode map we are caching really
belongs to a FS root instead of a special relocation tree.  It
prevents crashes during balancing operations.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:44 -04:00
Chris Mason
211f96c24f Btrfs: make sure we don't overflow the free space cache crc page
The free space cache uses only one page for crcs right now,
which means we can't have a cache file bigger than the
crcs we can fit in the first page.  This adds a check to
enforce that restriction.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:43 -04:00
Chris Mason
17aca1c987 Btrfs: fix uninit variable in the delayed inode code
The nitems counter needs to start at zero

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:43 -04:00
Arne Jansen
1bc8779349 btrfs: scrub: don't reuse bios and pages
The current scrub implementation reuses bios and pages as often as possible,
allocating them only on start and releasing them when finished. This leads
to more problems with the block layer than it's worth. The elevator gets
confused when there are more pages added to the bio than bi_size suggests.
This patch completely rips out the reuse of bios and pages and allocates
them freshly for each submit.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Maosn <chris.mason@oracle.com>
2011-06-04 08:03:17 -04:00
Linus Torvalds
4f1ba49efa Merge branch 'for-linus' of git://git.kernel.dk/linux-block
* 'for-linus' of git://git.kernel.dk/linux-block:
  block: Use hlist_entry() for io_context.cic_list.first
  cfq-iosched: Remove bogus check in queue_fail path
  xen/blkback: potential null dereference in error handling
  xen/blkback: don't call vbd_size() if bd_disk is NULL
  block: blkdev_get() should access ->bd_disk only after success
  CFQ: Fix typo and remove unnecessary semicolon
  block: remove unwanted semicolons
  Revert "block: Remove extra discard_alignment from hd_struct."
  nbd: adjust 'max_part' according to part_shift
  nbd: limit module parameters to a sane value
  nbd: pass MSG_* flags to kernel_recvmsg()
  block: improve the bio_add_page() and bio_add_pc_page() descriptions
2011-06-04 08:11:26 +09:00
Linus Torvalds
39b4a46f19 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier/blackfin
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier/blackfin:
  Blackfin: strncpy: fix handling of zero lengths
2011-06-04 08:04:10 +09:00
Linus Torvalds
cb37bbd90a Merge branch 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
* 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  asm-generic/unistd.h: support sendmmsg syscall
  tile: enable CONFIG_BUGVERBOSE
2011-06-04 08:03:16 +09:00
Linus Torvalds
3af91a1256 Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6:
  UBIFS: fix-up free space earlier
  UBIFS: intialize LPT earlier
  UBIFS: assert no fixup when writing a node
  UBIFS: fix clean znode counter corruption in error cases
  UBIFS: fix memory leak on error path
  UBIFS: fix shrinker object count reports
  UBIFS: fix recovery broken by the previous recovery fix
  UBIFS: amend ubifs_recover_leb interface
  UBIFS: introduce a "grouped" journal head flag
  UBIFS: supress false error messages
2011-06-04 07:59:32 +09:00
Linus Torvalds
9a44fde343 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-ktest
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-ktest:
  ktest: Ignore unset values of the minconfig in config_bisect
  ktest: Fix result of rebooting the kernel
  ktest: Fix off-by-one in config bisect result
2011-06-04 07:58:48 +09:00
Linus Torvalds
cd4ecf877a Merge branch 'rmobile-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* 'rmobile-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  ARM: mach-shmobile: add DMAC clock definitions on SH7372
  ARM: arch-shmobile: support SDHI card detection on mackerel, using a GPIO
  sh_mobile_meram: MERAM platform data for LCDC
2011-06-04 07:53:23 +09:00
Linus Torvalds
1f3bd0f2ac Merge branch 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  dmaengine: shdma: fix a regression: initialise DMA channels for memcpy
  dmaengine: shdma: Fix up fallout from runtime PM changes.
  Revert "clocksource: sh_cmt: Runtime PM support"
  Revert "clocksource: sh_tmu: Runtime PM support"
  sh: Fix up asm-generic/ptrace.h fallout.
  sh64: Move from P1SEG to CAC_ADDR for consistent sync.
  sh64: asm/pgtable.h needs asm/mmu.h
  sh: asm/tlb.h needs linux/swap.h
  sh: mark DMA slave ID 0 as invalid
  sh: Update shmin to reflect PIO dependency.
  sh: arch/sh/kernel/process_32.c needs linux/prefetch.h.
  sh: add MMCIF runtime PM support on ecovec
  sh: switch ap325rxa to dynamically manage the platform camera
2011-06-04 07:04:25 +09:00
Linus Torvalds
bb3d6bf191 Revert "ASoC: Update cx20442 for TTY API change"
This reverts commit ed0bd2333c.

Since we reverted the TTY API change, we should revert the ASoC update
to it too.

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Liam Girdwood <lrg@ti.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-04 07:00:50 +09:00
Linus Torvalds
55db4c64ed Revert "tty: make receive_buf() return the amout of bytes received"
This reverts commit b1c43f82c5.

It was broken in so many ways, and results in random odd pty issues.

It re-introduced the buggy schedule_work() in flush_to_ldisc() that can
cause endless work-loops (see commit a5660b41af: "tty: fix endless
work loop when the buffer fills up").

It also used an "unsigned int" return value fo the ->receive_buf()
function, but then made multiple functions return a negative error code,
and didn't actually check for the error in the caller.

And it didn't actually work at all.  BenH bisected down odd tty behavior
to it:
  "It looks like the patch is causing some major malfunctions of the X
   server for me, possibly related to PTYs.  For example, cat'ing a
   large file in a gnome terminal hangs the kernel for -minutes- in a
   loop of what looks like flush_to_ldisc/workqueue code, (some ftrace
   data in the quoted bits further down).

   ...

   Some more data: It -looks- like what happens is that the
   flush_to_ldisc work queue entry constantly re-queues itself (because
   the PTY is full ?) and the workqueue thread will basically loop
   forver calling it without ever scheduling, thus starving the consumer
   process that could have emptied the PTY."

which is pretty much exactly the problem we fixed in a5660b41af.

Milton Miller pointed out the 'unsigned int' issue.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-by: Milton Miller <miltonm@bga.com>
Cc: Stefan Bigler <stefan.bigler@keymile.com>
Cc: Toby Gray <toby.gray@realvnc.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-04 06:33:24 +09:00
John W. Linville
7b29dc21ea Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6 into for-davem 2011-06-03 14:31:50 -04:00
Eric Lammerts
157186bc18 ALSA: usb - turn off de-emphasis in s/pdif for cm6206
CM6206: Turn off de-emphasis channel status bit in S/PDIF output.

Signed-off-by: Eric Lammerts <eric@lammerts.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-06-03 18:22:56 +02:00