Using the guestmount option on record:
$ perf kvm --guest --host --guestmount=/tmp/guest-mount record -ag
But not the subsequent report:
$ perf kvm report
causes a SEGFAULT in the usual place:
(gdb) bt
0 0x0000000000470356 in machine__mmap_name (self=0x0, bf=0x7fffffffbdb0 " z\370\367\377\177", size=
4096) at util/map.c:712
1 0x00000000004453e8 in perf_event__process_kernel_mmap (tool=0x7fffffffde10, event=0x7ffff7f87e38,
machine=0x0) at util/event.c:550
2 0x00000000004458c9 in perf_event__process_mmap (tool=0x7fffffffde10, event=0x7ffff7f87e38, sample=
0x7fffffffd2a0, machine=0x0) at util/event.c:656
3 0x00000000004733e0 in perf_session_deliver_event (session=0x91aca0, event=0x7ffff7f87e38, sample=
0x7fffffffd2a0, tool=0x7fffffffde10, file_offset=7736) at util/session.c:979
...
The MMAP events in this case already contain the full path to the
module. No need to require it for the report path to.
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1341241977-71535-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 743eb86865 reworked when the
machines were created. Prior to this commit guest machines could be
created in perf_event__process_kernel_mmap() while processing kernel
MMAP events. This commit assumes that the machines exist by the time
perf_session_deliver_event is called (e.g., during processing of build
id events) - which is not always correct.
One example is the use of default guest args (--guestkallsyms and
--guestmodules) for short times where no samples hit within a guest
module. For this case no build id is added to the file header. No build
id == no machine created. That leads to the next example -- the use of
no-buildid (-B) on the record for all perf-kvm invocations. In both
cases perf report dies with a SEGFAULT of the form:
(gdb) bt
0 0x000000000046dd7b in machine__mmap_name (self=0x0, bf=0x7fffffffbd20 "q\021", size=4096) at util/map.c:715
1 0x0000000000444161 in perf_event__process_kernel_mmap (tool=0x7fffffffdd80, event=0x7ffff7fb4120, machine=0x0) at util/event.c:562
2 0x0000000000444642 in perf_event__process_mmap (tool=0x7fffffffdd80, event=0x7ffff7fb4120, sample=0x7fffffffd210, machine=0x0)
at util/event.c:668
3 0x0000000000470e0b in perf_session_deliver_event (session=0x915ca0, event=0x7ffff7fb4120, sample=0x7fffffffd210, tool=0x7fffffffdd80,
file_offset=8480) at util/session.c:979
4 0x000000000047032e in flush_sample_queue (s=0x915ca0, tool=0x7fffffffdd80) at util/session.c:679
5 0x0000000000471c8d in __perf_session__process_events (session=0x915ca0, data_offset=400, data_size=150448, file_size=150848, tool=
0x7fffffffdd80) at util/session.c:1363
6 0x0000000000471d42 in perf_session__process_events (self=0x915ca0, tool=0x7fffffffdd80) at util/session.c:1379
7 0x000000000042484a in __cmd_report (rep=0x7fffffffdd80) at builtin-report.c:368
8 0x0000000000425bf1 in cmd_report (argc=0, argv=0x915b00, prefix=0x0) at builtin-report.c:756
9 0x0000000000438505 in __cmd_report (argc=4, argv=0x7fffffffe260) at builtin-kvm.c:84
10 0x000000000043882a in cmd_kvm (argc=4, argv=0x7fffffffe260, prefix=0x0) at builtin-kvm.c:131
11 0x00000000004152cd in run_builtin (p=0x7a54e8, argc=9, argv=0x7fffffffe260) at perf.c:273
12 0x00000000004154c7 in handle_internal_command (argc=9, argv=0x7fffffffe260) at perf.c:345
13 0x0000000000415613 in run_argv (argcp=0x7fffffffe14c, argv=0x7fffffffe140) at perf.c:389
14 0x0000000000415899 in main (argc=9, argv=0x7fffffffe260) at perf.c:487
Fix by allowing the machine to be created in perf_session_deliver_event.
Tested with --guestmount option and default guest args, with and without
-B arg on record for both and for short (10 seconds) and long (10
minutes) windows.
Reported-by: Pradeep Kumar Surisetty <psuriset@linux.vnet.ibm.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pradeep Kumar Surisetty <psuriset@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1341180697-64515-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Consider the commands:
perf record -e sched:sched_switch -fo /tmp/perf.data -a -- sleep 1
perf script -i /tmp/perf.data
In v3.4 the output has the form (lines wrapped here)
perf 29214 [005] 821043.582596: sched_switch:
prev_comm=perf prev_pid=29214 prev_prio=120
prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
In 3.5 that same line has become:
perf 29214 [005] 821043.582596: sched_switch:
<...>-29214 [005] 0.000000000: sched_switch:
prev_comm=perf prev_pid=29214 prev_prio=120
prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
Note the duplicates in the output -- pid, cpu, event name. With
this patch the v3.4 output is restored:
perf 29214 [005] 821043.582596: sched_switch:
prev_comm=perf prev_pid=29214 prev_prio=120
prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
v3:
Remove that pesky newline too. Output now matches v3.4 (pre-libtracevent).
v2:
Change print_trace_event function local to perf per Steve's comments.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1339698977-68962-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The new_pages list head in the cpu_buffer is not initialized. When
adding pages to the ring buffer, if the memory allocation fails in
ring_buffer_resize, the clean up handler tries to free up the allocated
pages from all the cpu buffers. The panic is caused by referencing the
uninitialized new_pages list head.
Initializing the new_pages list head in rb_allocate_cpu_buffer fixes
this.
Link: http://lkml.kernel.org/r/1340391005-10880-1-git-send-email-vnagarnaik@google.com
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull Ceph fixes from Sage Weil:
"There are a couple of fixes from Yan for bad pointer dereferences in
the messenger code and when fiddling with page->private after page
migration, a fix from Alex for a use-after-free in the osd client
code, and a couple fixes for the message refcounting and shutdown
ordering."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: flush msgr queue during mon_client shutdown
rbd: Clear ceph_msg->bio_iter for retransmitted message
libceph: use con get/put ops from osd_client
libceph: osd_client: don't drop reply reference too early
ceph: check PG_Private flag before accessing page->private
Pull XFS fixes from Ben Myers:
- Fix stale data exposure with unwritten extents
- Fix a warning in xfs_alloc_vextent with ODEBUG
- Fix overallocation and alignment of pages for xfs_bufs
- Fix a cursor leak
- Fix a log hang
- Fix a crash related to xfs_sync_worker
- Rename xfs log structure from struct log to struct xlog so we can use
crash dumps effectively
* tag 'for-linus-Jun-21-2012' of git://oss.sgi.com/xfs/xfs:
xfs: rename log structure to xlog
xfs: shutdown xfs_sync_worker before the log
xfs: Fix overallocation in xfs_buf_allocate_memory()
xfs: fix allocbt cursor leak in xfs_alloc_ag_vextent_near
xfs: check for stale inode before acquiring iflock on push
xfs: fix debug_object WARN at xfs_alloc_vextent()
xfs: xfs_vm_writepage clear iomap_valid when !buffer_uptodate (REV2)
Pull perf updates from Ingo Molnar.
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ftrace: Make all inline tags also include notrace
perf: Use css_tryget() to avoid propping up css refcount
perf tools: Fix synthesizing tracepoint names from the perf.data headers
perf stat: Fix default output file
perf tools: Fix endianity swapping for adds_features bitmask
Pull NFS client bugfixes from Trond Myklebust:
- Fix a write hang due to an uninitalised variable when
!defined(CONFIG_NFS_V4)
- Address upcall races in the legacy NFSv4 idmapper
- Remove an O_DIRECT refcounting issue
- Fix a pNFS refcounting bug when the file layout metadata server is
also acting as a data server
- Fix a pNFS module loading race.
* tag 'nfs-for-3.5-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: Force the legacy idmapper to be single threaded
NFS: Initialise commit_info.rpc_out when !defined(CONFIG_NFS_V4)
NFS: Fix a refcounting issue in O_DIRECT
NFSv4.1: Fix a race in set_pnfs_layoutdriver
NFSv4.1: Fix umount when filelayout DS is also the MDS
Pull btrfs fixes from Chris Mason:
"This is a small pull with btrfs fixes. The biggest of the bunch is
another fix for the new backref walking code.
We're still hammering out one btrfs dio vs buffered reads problem, but
that one will have to wait for the next rc."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: delay iput with async extents
Btrfs: add a missing spin_lock
Btrfs: don't assume to be on the correct extent in add_all_parents
Btrfs: introduce btrfs_next_old_item
Pull hwmon fixes from Guenter Roeck:
"Two minor fixes in emc2103 and applesmc drivers."
* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (emc2103) Fix use of an uninitilized variable in error case
hwmon: (applesmc) Limit key length in warning messages
Rename the XFS log structure to xlog to help crash distinquish it from the
other logs in Linux.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
Revert commit 1307bbd, which uses the s_umount semaphore to provide
exclusion between xfs_sync_worker and unmount, in favor of shutting down
the sync worker before freeing the log in xfs_log_unmount. This is a
cleaner way of resolving the race between xfs_sync_worker and unmount
than using s_umount.
Signed-off-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Commit de1cbee which removed b_file_offset in favor of b_bn introduced a bug
causing xfs_buf_allocate_memory() to overestimate the number of necessary
pages. The problem is that xfs_buf_alloc() sets b_bn to -1 and thus effectively
every buffer is straddling a page boundary which causes
xfs_buf_allocate_memory() to allocate two pages and use vmalloc() for access
which is unnecessary.
Dave says xfs_buf_alloc() doesn't need to set b_bn to -1 anymore since the
buffer is inserted into the cache only after being fully initialized now.
So just make xfs_buf_alloc() fill in proper block number from the beginning.
CC: David Chinner <dchinner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
When we fail to find an matching extent near the requested extent
specification during a left-right distance search in
xfs_alloc_ag_vextent_near, we fail to free the original cursor that
we used to look up the XFS_BTNUM_CNT tree and hence leak it.
Reported-by: Chris J Arges <chris.j.arges@canonical.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
An inode in the AIL can be flush locked and marked stale if
a cluster free transaction occurs at the right time. The
inode item is then marked as flushing, which causes xfsaild
to spin and leaves the filesystem stalled. This is
reproduced by running xfstests 273 in a loop for an
extended period of time.
Check for stale inodes before the flush lock. This marks
the inode as pinned, leads to a log flush and allows the
filesystem to proceed.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
The OProfile perf backend uses a static array to keep track of the
perf events on the system. When compiling with CONFIG_CPUMASK_OFFSTACK=y
&& SMP, nr_cpumask_bits is not a compile-time constant and the build
will fail with:
oprofile_perf.c:28: error: variably modified 'perf_events' at file scope
This patch uses NR_CPUs instead of nr_cpumask_bits for the array
initialisation. If this causes space problems in the future, we can
always move to dynamic allocation for the events array.
Cc: Matt Fleming <matt@console-pimps.org>
Reported-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org> # v2.6.37+
Signed-off-by: Robert Richter <robert.richter@amd.com>
There is some concern that these iput()'s could be the final iputs and could
induce lockups on people waiting on writeback. This would happen in the
rare case that we don't create ordered extents because of an error, but it
is theoretically possible and we already have a mechanism to deal with this
so just make them delayed iputs to negate any worry.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
When fixing up the locking in the delayed ref destruction work I accidently
broke the locking myself ;(. Add back a spin_lock that should be there and
we are now all set. Thanks,
Btrfs: add a missing spin_lock
When fixing up the locking in the delayed ref destruction work I accidently
broke the locking myself ;(. Add back a spin_lock that should be there and
we are now all set. Thanks,
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
add_all_parents did assume that path is already at a correct extent data
item, which may not be true in case of data extents that were partly
rewritten and splitted.
We need to check if we're on a matching extent for every item and only
for the ones after the first. The loop is changed to do this now.
This patch also fixes a bug introduced with commit 3b127fd8 "Btrfs:
remove obsolete btrfs_next_leaf call from __resolve_indirect_ref".
The removal of next_leaf did sometimes result in slot==nritems when
the above described case happens, and thus resulting in invalid values
(e.g. wanted_obejctid) in add_all_parents (leading to missed backrefs
or even crashes).
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We introduce btrfs_next_old_item that uses btrfs_next_old_leaf instead
of btrfs_next_leaf.
btrfs_next_item is also changed to simply call btrfs_next_old_item with
time_seq being 0.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Pull slave-dmaengine fixes from Vinod Koul:
"A few fixes in pl330 and imx-sdma drivers."
* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
DMA: PL330: Fix racy mutex unlock
DMA: PL330: Add missing static storage class specifier
dma: imx-sdma: buf_tail should be initialize in prepare function
dmaengine: pl330: dont complete descriptor for cyclic dma
Pull two cgroup fixes from Tejun Heo:
"This containes two patches fixing a refcnt race bug during css_put().
Decrementing and checking the value weren't atomic and two tasks could
think that they both pushed the counter to zero."
* 'for-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroups: Account for CSS_DEACT_BIAS in __css_put
cgroup: make sure that decisions in __css_put are atomic
Ingo Molnar
David Ahern
Vaibhav Nagarnaik
Linus Torvalds
Mark Tinguely
Ben Myers
Jan Kara
Dave Chinner
Brian Foster
Will Deacon
Josef Bacik
Alexander Block