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  1. 03 Jul, 2010 1 commit
  3. 01 Jul, 2010 1 commit
  5. 30 Jun, 2010 1 commit
    • Frederic Weisbecker's avatar
      x86: Send a SIGTRAP for user icebp traps · a1e80faf
      Frederic Weisbecker authored 
      Before we had a generic breakpoint layer, x86 used to send a
sigtrap for any debug event that happened in userspace,
except if it was caused by lazy dr7 switches.

Currently we only send such signal for single step or breakpoint
events.

However, there are three other kind of debug exceptions:

- debug register access detected: trigger an exception if the
  next instruction touches the debug registers. We don't use
  it.
- task switch, but we don't use tss.
- icebp/int01 trap. This instruction (0xf1) is undocumented and
  generates an int 1 exception. Unlike single step through TF
  flag, it doesn't set the single step origin of the exception
  in dr6.

icebp then used to be reported in userspace using trap signals
but this have been incidentally broken with the new breakpoint
code. Reenable this. Since this is the only debug event that
doesn't set anything in dr6, this is all we have to check.

This fixes a regression in Wine where World Of Warcraft got broken
as it uses this for software protection checks purposes. And
probably other apps do.
Reported-and-tested-by: default avatarAlexandre Julliard <julliard@winehq.org>
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: 2.6.33.x 2.6.34.x <stable@kernel.org>
      a1e80faf
  7. 21 Jun, 2010 1 commit
  9. 17 Jun, 2010 2 commits
    • Ian Munsie's avatar
      perf record: prevent kill(0, SIGTERM); · 5ffc8881
      Ian Munsie authored 
      At exit, perf record will kill the process it was profiling by sending a
SIGTERM to child_pid (if it had been initialised), but in certain situations
child_pid may be 0 and perf would mistakenly kill more processes than intended.

child_pid is set to the return of fork() to either 0 or the pid of the child.
Ordinarily this would not present an issue as the child calls execvp to spawn
the process to be profiled and would therefore never run it's sig_atexit and
never attempt to kill pid 0.

However, if a nonexistant binary had been passed in to perf record the call to
execvp would fail and child_pid would be left set to 0. The child would then
exit and it's atexit handler, finding that child_pid was initialised to 0,
would call kill(0, SIGTERM), resulting in every process within it's process
group being killed.

In the case that perf was being run directly from the shell this typically
would not be an issue as the shell isolates the process.  However, if perf was
being called from another program it could kill unexpected processes, which may
even include X.

This patch changes the logic of the test for whether child_pid was initialised
to only consider positive pids as valid, thereby never attempting to kill pid
0.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <1276072680-17378-1-git-send-email-imunsie@au1.ibm.com>
Signed-off-by: default avatarIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      5ffc8881
    • Arnaldo Carvalho de Melo's avatar
      perf session: Remove threads from tree on PERF_RECORD_EXIT · 720a3aeb
      Arnaldo Carvalho de Melo authored 
      Move them to a session->dead_threads list just like we do with maps that
are replaced, because we may have hist_entries pointing to them.

This fixes a bug when inserting maps for a new thread that reused the
TID, mixing maps for two different threads, causing an endless loop.

The code for insering maps should be made more robust but for .35 this
is the minimalistic patch.
Reported-by: default avatarIngo Molnar <mingo@elte.hu>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      720a3aeb
  11. 11 Jun, 2010 2 commits
  13. 10 Jun, 2010 2 commits
  15. 08 Jun, 2010 4 commits
  17. 07 Jun, 2010 1 commit
  19. 04 Jun, 2010 2 commits
  21. 03 Jun, 2010 1 commit
    • Peter Zijlstra's avatar
      perf: Fix crash in swevents · c6df8d5a
      Peter Zijlstra authored 
      Frederic reported that because swevents handling doesn't disable IRQs
anymore, we can get a recursion of perf_adjust_period(), once from
overflow handling and once from the tick.

If both call ->disable, we get a double hlist_del_rcu() and trigger
a LIST_POISON2 dereference.

Since we don't actually need to stop/start a swevent to re-programm
the hardware (lack of hardware to program), simply nop out these
callbacks for the swevent pmu.
Reported-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1275557609.27810.35218.camel@twins>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      c6df8d5a
  23. 02 Jun, 2010 1 commit
  25. 01 Jun, 2010 3 commits
    • Arnaldo Carvalho de Melo's avatar
      perf buildid-list: Fix --with-hits event processing · b5c874f1
      Arnaldo Carvalho de Melo authored 
      When we use plain 'perf buildid-list' we use only what is in the buildid
table in the perf.data header. And those have absolute pathnames because
at 'perf record' time we used __perf_session__process_events and that
doesn't sets up the path shortening code in map__new() that happens if
symbol_conf.full_paths is false, the default.

On the other hand, when we use 'perf buildid-list --with-hits' we
process all the events using perf_session__process_events, adding
entries to the global DSO list _after_ removing the current directory
from the DSO name, for presentation purposes.

Because of that we end up having two entries in the DSO list when
recording events for binaries using relative pathnames.

Fix it minimally by setting symbol_conf.full_paths to true when marking
the DSOs with hits in 'perf buildid-list --with-hits', as used by 'perf
archive'

Right fix longer term is to shorten the path only at presentation time.
Will be done for 2.6.36.
Reported-by: default avatarStephane Eranian <eranian@google.com>
Tested-by: default avatarStephane Eranian <eranian@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20100601183837.GC4093@ghostprotocols.net>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      b5c874f1
    • Pierre Tardy's avatar
      perf scripts python: Give field dict to unhandled callback · c0251485
      Pierre Tardy authored 
      trace_unhandled() callback does not allow to access event fields, this patch
resolves the problem.

It can also been used as a more pythonic and flexible way for script writters
to demux event types

This will for example greatly simplify pytimechart event demux.
Acked-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: default avatarTom Zanussi <tzanussi@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>,
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <1275340329-2397-1-git-send-email-tardyp@gmail.com>
Signed-off-by: default avatarPierre Tardy <tardyp@gmail.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      c0251485
    • Konstantin Stepanyuk's avatar
      perf hist: fix objdump output parsing · 75d9ef17
      Konstantin Stepanyuk authored 
      hist_entry__annotate() runs objdump with -S option so the output may contain
lines of any format. If a line starts with a colon strtoull() returns 0 and
calculated offset will be negative. This causes perf annotate segfaults.

Make sure that strtoull() has parsed at least one digit.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: default avatarKonstantin Stepanyuk <konstantin.stepanyuk@gmail.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      75d9ef17
  27. 31 May, 2010 11 commits
    • Borislav Petkov's avatar
      perf-record: Check correct pid when forking · 2fb750e8
      Borislav Petkov authored 
      When forking the child to be traced, we should check the correct
return value from fork() and not a local variable which is otherwise
unused.
Signed-off-by: default avatarBorislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <20100531211818.GA30175@liondog.tnic>
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      2fb750e8
    • Frederic Weisbecker's avatar
      perf: Do the comm inheritance per thread in event__process_task · dd833d71
      Frederic Weisbecker authored 
      event__process_task() doesn't propagate the comm copy on clone,
but only on process fork. So we loose all the tid:comm resolution
for tasks that aren't a main process thread.

Progragate the per thread granularity to event__process_task for
pid resolution.

This fixes various unresolved pids in perf sched, especially when
we trace multithread processes. The problem is quickly reproducible
with the messaging benchmark using the multithread mode "-t" :

	perf sched record perf bench sched messaging -t
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
      dd833d71
    • Frederic Weisbecker's avatar
      perf: Use event__process_task from perf sched · af64865b
      Frederic Weisbecker authored 
      perf sched uses event__process_comm(), which means it can resolve
comms from:

- tasks that have exec'ed (kernel comm events)
- tasks that were running when perf record started the actual
  recording (synthetized comm events)

But perf sched can't resolve the pids of tasks that were created
after the recording started.

To solve this, we need to inherit the comms on fork events using
event__process_task().

This fixes various unresolved pids in perf sched, easily visible
with:
	perf sched record perf bench sched messaging
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
      af64865b
    • Frederic Weisbecker's avatar
      perf: Process comm events by tid · 13eb04fd
      Frederic Weisbecker authored 
      When we synthetize the existing running tasks though procfs,
we walk through every threads of a process, queuing one comm
events per tid.

But then on report time, event__process_comm() only creates and
sets the comm on a per process granularity. This is the right
thing for comm events that came from the kernel, as they are
only created on exec. Sub-threads then inherit their comm
from fork events. But that doesn't work with our synthetized
comm events taken from procfs informations as the per thread
granularity is done on comm events directly there.

Hence we need event__process_comm() to work with the tid rather
than the pid. It won't change anything for comm events coming
from the kernel but this will fix the synthetized ones.

Before:

	$ ./perf report -D | grep COMM | grep firefox

	0x2c7b8 [0x18]: PERF_RECORD_COMM: firefox:5297
	0x2c7d0 [0x18]: PERF_RECORD_COMM: firefox:5297
	0x2c7e8 [0x18]: PERF_RECORD_COMM: firefox:5297
	0x2c800 [0x18]: PERF_RECORD_COMM: firefox:5297
	0x2c818 [0x18]: PERF_RECORD_COMM: firefox:5297
	0x2c830 [0x18]: PERF_RECORD_COMM: firefox:5297

After:
	$ ./perf report -D | grep COMM | grep firefox

	0x2c7b8 [0x18]: PERF_RECORD_COMM: firefox:5297
	0x2c7d0 [0x18]: PERF_RECORD_COMM: firefox:5299
	0x2c7e8 [0x18]: PERF_RECORD_COMM: firefox:5300
	0x2c800 [0x18]: PERF_RECORD_COMM: firefox:5308
	0x2c818 [0x18]: PERF_RECORD_COMM: firefox:5309
	0x2c830 [0x18]: PERF_RECORD_COMM: firefox:5312

This fixes various unresolved pid on perf sched.
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
      13eb04fd
    • Randy Dunlap's avatar
      blktrace: Fix new kernel-doc warnings · 546cf44a
      Randy Dunlap authored 
      Fix blktrace.c kernel-doc warnings:
 Warning(kernel/trace/blktrace.c:858): No description found for parameter 'ignore'
 Warning(kernel/trace/blktrace.c:890): No description found for parameter 'ignore'
Signed-off-by: default avatarRandy Dunlap <randy.dunlap@oracle.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100529114507.c466fc1e.randy.dunlap@oracle.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      546cf44a
    • Frederic Weisbecker's avatar
      perf_events: Fix unincremented buffer base on partial copy · 74048f89
      Frederic Weisbecker authored 
      If a sample size crosses to the next page boundary, the copy
will be made in more than one step. However we forget to advance
the source offset for the next copy, leading to unexpected double
copies that completely mess up the traces.

This fixes various kinds of bad traces that have irrelevant
data inside, as an example:

	geany-4979  [001]  5758.077775: sched_switch: prev_comm=! prev_pid=121
		prev_prio=0 prev_state=S|D|Z|X|x ==> next_comm= next_pid=7497072
		next_prio=0
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1274988898-5639-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      74048f89
    • Stephane Eranian's avatar
      perf_events: Fix event scheduling issues introduced by transactional API · 90151c35
      Stephane Eranian authored 
      The transactional API patch between the generic and model-specific
code introduced several important bugs with event scheduling, at
least on X86. If you had pinned events, e.g., watchdog,  and were
over-committing the PMU, you would get bogus counts. The bug was
showing up on Intel CPU because events would move around more
often that on AMD. But the problem also existed on AMD, though
harder to expose.

The issues were:

 - group_sched_in() was missing a cancel_txn() in the error path

 - cpuc->n_added was not properly maintained, leading to missing
   actions in hw_perf_enable(), i.e., n_running being 0. You cannot
   update n_added until you know the transaction has succeeded. In
   case of failed transaction n_added was not adjusted back.

 - in case of failed transactions, event_sched_out() was called
   and eventually invoked x86_disable_event() to touch the HW reg.
   But with transactions, on X86, event_sched_in() does not touch
   HW registers, it simply collects events into a list. Thus, you
   could end up calling x86_disable_event() on a counter which
   did not correspond to the current event when idx != -1.

The patch modifies the generic and X86 code to avoid all those problems.

First, we keep track of the number of events added last. In case the
transaction fails, we substract them from n_added. This approach is
necessary (as opposed to delaying updates to n_added) because not all
event updates use the transaction API, e.g., single events.

Second, we encapsulate the event_sched_in() and event_sched_out() in
group_sched_in() inside the transaction. That makes the operations
symmetrical and you can also detect that you are inside a transaction
and skip the HW reg access by checking cpuc->group_flag.

With this patch, you can now overcommit the PMU even with pinned
system-wide events present and still get valid counts.
Signed-off-by: default avatarStephane Eranian <eranian@google.com>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1274796225.5882.1389.camel@twins>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      90151c35
    • Peter Zijlstra's avatar
      perf_events, trace: Fix perf_trace_destroy(), mutex went missing · 2e97942f
      Peter Zijlstra authored 
      Steve spotted I forgot to do the destroy under event_mutex.
Reported-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1274451913.1674.1707.camel@laptop>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      2e97942f
    • Peter Zijlstra's avatar
      perf_events, trace: Fix probe unregister race · 3771f077
      Peter Zijlstra authored 
      tracepoint_probe_unregister() does not synchronize against the probe
callbacks, so do that explicitly. This properly serializes the callbacks
and the free of the data used therein.

Also, use this_cpu_ptr() where possible.
Acked-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1274438476.1674.1702.camel@laptop>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      3771f077
    • Peter Zijlstra's avatar
      perf_events: Fix races in group composition · 8a49542c
      Peter Zijlstra authored 
      Group siblings don't pin each-other or the parent, so when we destroy
events we must make sure to clean up all cross referencing pointers.

In particular, for destruction of a group leader we must be able to
find all its siblings and remove their reference to it.

This means that detaching an event from its context must not detach it
from the group, otherwise we can end up failing to clear all pointers.

Solve this by clearly separating the attachment to a context and
attachment to a group, and keep the group composed until we destroy
the events.
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      8a49542c
    • Peter Zijlstra's avatar
      perf_events: Fix races and clean up perf_event and perf_mmap_data interaction · ac9721f3
      Peter Zijlstra authored 
      In order to move toward separate buffer objects, rework the whole
perf_mmap_data construct to be a more self-sufficient entity, one
with its own lifetime rules.

This greatly sanitizes the whole output redirection code, which
was riddled with bugs and races.
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      ac9721f3
  29. 30 May, 2010 7 commits
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