Add a new flag field while opening a tracepoint perf counter:
-e tracepoint_subsystem:tracepoint_name:flags
This is intended to be generic although for now it only supports the
r[e[c[o[r[d]]]]] flag:
./perf record -e workqueue:workqueue_insertion:record
./perf record -e workqueue:workqueue_insertion:r
will have the same effect: enabling the raw samples record for
the given tracepoint counter.
In the future, we may want to support further flags, separated
by commas.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1250152039-7284-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Provide weak aliases for hw_perf_counter_setup_online(). This is
used by the BTS patches (for v2.6.32), but it interacts with
fixes so propagate this upstream. (it has no effect as of yet)
Also export perf_counter_output() to architecture code.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When /sys/kernel/debug is mounted the list can be imense, so
use the pager like the other tools.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090812174459.GB3495@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The driver always:
1. allocate cp->rx_buf_sz + NET_IP_ALIGN
2. map cp->rx_buf_sz
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert the AP325RXA board code to register devices at
arch_initcall() time instead of device_initcall(). This
fix unbreaks pcf8563 RTC driver support.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Convert the Migo-R board code to register devices at
arch_initcall() time instead of __initcall(). This fix
unbreaks migor_ts touch screen driver support.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Convert the processor platform device setup
functions from __initcall() and sometimes
device_initcall() to arch_initcall().
This makes sure that the platform devices are
registered a bit earlier so the devices are
available when drivers register using initcall
levels earlier than device_initcall().
A good example is platform devices needed by
i2c-sh_mobile.c which registers a bit earlier
using subsys_initcall().
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Normally we only allow the upper limit for a reshape to be decreased
when the array not performing a sync/recovery/reshape, otherwise there
could be races. But if an array is part-way through a reshape when it
is assembled the reshape is started immediately leaving no window
to set an upper bound.
If the array is started read-only, the reshape will be suspended until
the array becomes writable, so that provides a window during which it
is perfectly safe to reduce the upper limit of a reshape.
So: allow the upper limit (sync_max) to be reduced even if the reshape
thread is running, as long as the array is still read-only.
Signed-off-by: NeilBrown <neilb@suse.de>
We were removing the drives, from the array, but not
removing symlinks from /sys/.... and not marking the device
as having been removed.
Signed-off-by: NeilBrown <neilb@suse.de>
This reverts commit 57921c312e.
On request from John Linville:
It has been shown to create a new problem. There is work
towards a solution to that one, but it isn't a simple
clean-up.
Signed-off-by: David S. Miller <davem@davemloft.net>
This "if" don't allow for the possibility that the number of devices
doesn't change, and so sector_nr isn't set correctly in that case.
So change '>' to '>='.
Signed-off-by: NeilBrown <neilb@suse.de>
md/raid5 doesn't allow a reshape to restart if it involves writing
over the same part of disk that it would be reading from.
This happens at the beginning of a reshape that increases the number
of devices, at the end of a reshape that decreases the number of
devices, and continuously for a reshape that does not change the
number of devices.
The current code is correct for the "increase number of devices"
case as the critical section at the start is handled by userspace
performing a backup.
It does not work for reducing the number of devices, or the
no-change case.
For 'reducing', we need to invert the test. For no-change we cannot
really be sure things will be safe, so simply require the array
to be read-only, which is how the user-space code which carefully
starts such arrays works.
Signed-off-by: NeilBrown <neilb@suse.de>
When assembling arrays, md allows two devices to have different event
counts as long as the difference is only '1'. This is to cope with
a system failure between updating the metadata on two difference
devices.
However there are currently times when we update the event count by
2. This was done to keep the event count even when the array is clean
and odd when it is dirty, which allows us to avoid writing common
update to spare devices and so allow those spares to go to sleep.
This is bad for the above reason. So change it to never increase by
two. This means that the alignment between 'odd/even' and
'clean/dirty' might take a little longer to attain, but that is only a
small cost. The spares will get a few more updates but that will
still be spared (;-) most updates and can still go to sleep.
Prior to this patch there was a small chance that after a crash an
array would fail to assemble due to the overly large event count
mismatch.
Signed-off-by: NeilBrown <neilb@suse.de>
commit fd51d251e4
Author: Stefan Raspl <raspl@linux.vnet.ibm.com>
Date: Tue May 19 09:59:08 2009 +0200
blktrace: remove debugfs entries on bad path
added in an explicit invocation of debugfs_remove for bt->dir, in
blk_remove_buf_file_callback we are also getting the directory removed. On
occasion I am seeing memory corruption that I have bisected down to
this commit. [The testing involves a (long) series of I/O benchmarks
with blktrace invoked around the actual runs.] I believe that this
committed patch is correct, but the problem actually lies in the code
in blk_remove_buf_file_callback.
With this patch I am able to consistently get complete runs whereas
previously I could not get a single run to complete.
The first part of the patch simply moves the debugfs_remove below the
relay_close: the relay_close call will remove files under bt->dir, and
so we should not remove the directory until all the files we created
have been removed. (Note: This is not sufficient to fix the problem -
the file system code has ref counts on the directoy, so our invocation
does not cause the directory to actually be removed. Nonetheless, we
should not rely upon that feature.)
Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
xfs: fix spin_is_locked assert on uni-processor builds
xfs: check for dinode realtime flag corruption
use XFS_CORRUPTION_ERROR in xfs_btree_check_sblock
xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_get
xfs: switch to NOFS allocation under i_lock in xfs_readlink_bmap
xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_set
xfs: switch to NOFS allocation under i_lock in xfs_buf_associate_memory
xfs: switch to NOFS allocation under i_lock in xfs_dir_cilookup_result
xfs: switch to NOFS allocation under i_lock in xfs_da_buf_make
xfs: switch to NOFS allocation under i_lock in xfs_da_state_alloc
xfs: switch to NOFS allocation under i_lock in xfs_getbmap
xfs: avoid memory allocation under m_peraglock in growfs code
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
ahci: add workaround for on-board 5723s on some gigabyte boards
ahci: Soften up the dmesg on SB600 PMP softreset failure recovery
Documentation/kernel-parameters.txt: document libata's ignore_hpa option
sata_nv: MSI support, disabled by default
libata: OCZ Vertex can't do HPA
pata_atiixp: fix second channel support
pata_at91: fix resource release
We can't call nfs_readdata_release()/nfs_writedata_release() without
first initialising and referencing args.context. Doing so inside
nfs_direct_read_schedule_segment()/nfs_direct_write_schedule_segment()
causes an Oops.
We should rather be calling nfs_readdata_free()/nfs_writedata_free() in
those cases.
Looking at the O_DIRECT code, the "struct nfs_direct_req" is already
referencing the nfs_open_context for us. Since the readdata and writedata
structures carry a reference to that, we can simplify things by getting rid
of the extra nfs_open_context references, so that we can replace all
instances of nfs_readdata_release()/nfs_writedata_release().
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Stezenbach reported that his Pentium-M based
laptop does not have the local APIC enabled by default,
and hence perfcounters do not get initialized.
Add a fallback for this case: allow non-sampled counters
and return with an error on sampled counters. This allows
'perf stat' to work out of box - and allows 'perf top'
and 'perf record' to fall back on a hrtimer based sampling
method.
( Passing 'lapic' on the boot line will allow hardware
sampling to occur - but if the APIC is disabled
permanently by the hardware then this fallback still
allows more systems to use perfcounters. )
Also decouple perfcounter support from X86_LOCAL_APIC.
-v2: fix typo breaking counters on all other systems ...
Reported-by: Johannes Stezenbach <js@sig21.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf top supports a -C for setting the profile CPU, but perf
record does not. This adds the same option for perf record,
allowing the user to specify a specific target profile CPU.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090812091801.GC12579@kernel.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It is better than showing the map addr, this way at least we
know that we can't get the symtabs because the DSO was deleted
(system update) while an app still used such DSO.
Yeah, don't do that, but if you do, you'll figure it out
quicker this way.
[acme@doppio linux-2.6-tip]$ perf report | head -15
# Samples: 3796
#
# Overhead Command Shared Object Symbol
# ........ ....... ................................................................... ......
#
23.55% pidgin /lib64/libglib-2.0.so.0.2000.4.#prelink#.Pd98lu (deleted) [.] 0x00000000038844
21.55% pidgin /lib64/libpthread-2.10.1.so.#prelink#.AFwK8Q (deleted) [.] 0x0000000000a42d
10.85% pidgin [kernel] [.] vread_hpet
7.85% pidgin /lib64/libgobject-2.0.so.0.2000.4.#prelink#.o1vpU7 (deleted) [.] 0x00000000014de8
3.35% pidgin /lib64/libc-2.10.1.so (deleted) [.] 0x0000000007a875
3.19% pidgin /lib64/libdbus-1.so.3.4.0.#prelink#.6mwgZP (deleted) [.] 0x0000000001d254
3.06% pidgin /usr/lib64/libgtk-x11-2.0.so.0.1600.5.#prelink#.511hAl (deleted) [.] 0x000000002334e7
2.90% pidgin /usr/lib64/libgdk-x11-2.0.so.0.1600.5.#prelink#.5qlMo1 (deleted) [.] 0x00000000037b2d
1.84% pidgin [kernel] [k] do_sys_poll
1.45% pidgin /usr/lib64/libX11.so.6.2.0.#prelink#.iR59Rx (deleted) [.] 0x0000000004c751
[acme@doppio linux-2.6-tip]$
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Luis Claudio R. Gonçalves <lclaudio@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090811200436.GA3478@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In old binutils we can't access bfd_demangle(), use
cplus_demangle() just like oprofile.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Luis Claudio R. Gonçalves <lclaudio@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090811192211.GG18061@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This made it easier to find the firefox threading related
bug.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090811192138.GE18061@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Noticed when trying to record events for a firefox thread. We
were synthesizing both .tid and .pid with the pid passed via
--pid.
Fix it by reading /proc/PID/status and getting the tgid
to use in .pid, .tid gets the specified "pid".
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <20090811192200.GF18061@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some gigabytes have on-board SIMG5723s connected to JMB ahcis. These
are used to implement hardware raid. Unfortunately some firmware
revisions on these 5723s don't bring the link down when all the
downstream ports are unoccupied while not responding to reset protocol
which makes libata think that there's device attached to the port but
is not responding and retry. This results in painfully wrong boot
detection time for these ports when they're empty.
This patch quirks those boards such that ahci gives up after the
initial timeout. Combined with parallel probing, this gives quick
enough probing and also is safe because SIMG5723 will respond to the
first try if any of the downstream ports is occupied.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Marc Bowes <marcbowes@gmail.com>
Reported-by: Nicolas Mailhot <Nicolas.Mailhot@LaPoste.net>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Too strong words led to spurious bug reports: Novell bugzilla #527748,
RedHat bugzilla #468800. This patch is used to soften up the dmesg on
SB600 PMP softreset failure recovery, so as to remove the scariness and
concern from community.
Reported-by: pgnet Dev <pgnet.dev@gmail.com>
Signed-off-by: Shane Huang <shane.huang@amd.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
By default the kernel honors the HPA (host protected area) of hard
drives. Using libata's ignore_hpa module option it's possible to
change this behaviour.
Document usage and options of libata.ignore_hpa in
Documentation/kernel-parameters.txt.
Signed-off-by: Michael Prokop <mika@grml.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
At least the nVidia MCP55 controller quite happily supports MSI.
This adds an option to use it. It is disabled by default.
As per feedback by Robert Hancock, it will honour the user
request as the kernel will not enable MSI where the controller
or the specific system configuration do not support it.
Signed-off-by: Tony Vroon <tony@linx.net>
Cc: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
OCZ Vertex SSD can't do HPA and not in a usual way. It reports HPA,
allows unlocking but then fails all IOs which fall in the unlocked
area. Quirk it so that HPA unlocking is not used for the device.
Reported by Daniel Perup in bnc#522414.
https://bugzilla.novell.com/show_bug.cgi?id=522414
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Daniel Perup <probe@spray.se>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
PIO and MWDMA timings are never programmed for the second channel
because timing registers are treated as 16-bit long ones.
The bug is an attixp -> pata_atiixp regression and goes back to:
commit 669a5db411
Author: Jeff Garzik <jeff@garzik.org>
Date: Tue Aug 29 18:12:40 2006 -0400
[libata] Add a bunch of PATA drivers.
Cc: Krystian Juskowiak <jusko@tlen.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bbpetkov@yahoo.de>
Cc: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Julias Lawall discovered that pata_at91 wasn't freeing a memory region
allocated with kzalloc() on init failure paths. Upon review,
pata_at91 also seems to be doing unnecessary explicit resource
releases for managed resources too. Convert memory allocation to
managed one and drop unnecessary explicit resource releases.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Julia Lawall <julia@diku.dk>
Cc: Sergey Matyukevich <geomatsi@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Kernel is broken for x86 CPUs without CPUID since 2.6.28. It
crashes with NULL pointer dereference in identify_cpu():
766 generic_identify(c);
767
768--> if (this_cpu->c_identify)
769 this_cpu->c_identify(c);
this_cpu is NULL. This is because it's only initialized in
get_cpu_vendor() function, which is not called if the CPU has
no CPUID instruction.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
LKML-Reference: <200908112000.15993.linux@rainbow-software.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Without SMP or preemption spin_is_locked always returns false,
so we can't do an assert with it. Instead use assert_spin_locked,
which does the right thing on all builds.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Reported-by: Johannes Engel <jcnengel@googlemail.com>
Tested-by: Johannes Engel <jcnengel@googlemail.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Ramon tested XFS with a modified version of fsfuzzer and hit a NULL
pointer dereference in __xfs_get_blocks due to the RT device target
pointer being NULL.
To fix this reject inode with the realtime bit set on a a filesystem
without an RT subvolume during inode read.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Reported-by: Ramon de Carvalho Valle <ramon@risesecurity.org>
Tested-by: Ramon de Carvalho Valle <ramon@risesecurity.org>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
In Red Hat Bug 512552
- Can't write to XFS mount during raid5 resync
a user ran into corruption while resyncing a raid, and we failed
a consistency test, but didn't get much more info; it'd be nice
to call XFS_CORRUPTION_ERROR here so we can see the buffer
contents.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_attr_rmtval_get is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_readlink_bmap is called with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_attr_rmtval_set is always called with i_lock held, and i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_buf_associate_memory is used for setting up the spare buffer for the
log wrap case in xlog_sync which can happen under i_lock when called from
xfs_fsync. The i_lock mutex is taken in reclaim context so all allocations
under it must avoid recursions into the filesystem. There are a couple
more uses of xfs_buf_associate_memory in the log recovery code that are
also affected by this, but I'd rather keep the code simple than passing on
a gfp_mask argument. Longer term we should just stop requiring the memoery
allocation in xlog_sync by some smaller rework of the buffer layer.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_dir_cilookup_result is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into the
filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
i_lock is taken in the reclaim context so all allocations under it
must avoid recursions into the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_da_state_alloc is always called with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into the
filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_getbmap allocates memory with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Allocate the memory for the larger m_perag array before taking the
per-AG lock as the per-AG lock can be taken under the i_lock which
can be taken from reclaim context.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>