We compute the perf raw sample size by aligning the raw ftrace
event size plus the buffer size field itself. We do that
instead of aligning only the perf raw sample size, so that we
might economize some in some cases.

But this buffer size field is not stored in the perf raw
sample, we must then substract its size from the buffer once we
computed the alignment unless we may get a useless u32 field in
the buffer.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20090810141129.GA5124@nowhere>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Raw tracepoint data contains various kernel internals and
data from other users, so restrict this to CAP_SYS_ADMIN.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249896452.17467.75.camel@twins>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

PERF_SAMPLE_* output switches should unconditionally output the
correct format, as they are the only way to unambiguously parse
the PERF_EVENT_SAMPLE data.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249896447.17467.74.camel@twins>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Sometimes we get callchain branches that have a rate under the
limit given by the user.

Say you launched:

 perf record -f -g -a ./hackbench 10
 perf report -g fractal,10.0

And you got:

2.33%       hackbench  [kernel]                  [k] _spin_lock_irqsave
                |
                |--78.57%-- remove_wait_queue
                |          poll_freewait
                |          do_sys_poll
                |          sys_poll
                |          sysenter_dispatch
                |          0xf7ffa430
                |          0x1ffadea3c
                |
                |--7.14%-- __up_read
                |          up_read
                |          do_page_fault
                |          page_fault
                |          0xf7ffa430
                |          0xa0df710000000a
                ...

It is abnormal to get a 7.14% branch whereas we passed a 10%
filter.

The problem is that we round down the minimum threshold. This
happens mostly when we have very low number of events. If the
total amount of your branch is 4 and you have a subranch of 3
events, filtering to 90% will be computed like follows:

  limit = 4 * 0.9;

The result is about 3.6, but the cast to integer will round
down to 3. It means that our filter is actually of 75%

We must then explicitly round up the minimum threshold.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: acme@redhat.com
Cc: peterz@infradead.org
Cc: efault@gmx.de
LKML-Reference: <20090809024235.GA10146@nowhere>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Due to a libz dependency in some distro's binutils package,
C++ demangle support isn't compiled in despite the necessary
libraries being available.

Fix this by adding a -lz link test to the dependency detection
rules.
Signed-off-by: NMike Galbraith <efault@gmx.de>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1249733655.6929.5.camel@marge.simson.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

A few examples of how 'perf' can be used, from an e-mail by
Ingo Molnar http://lkml.org/lkml/2009/8/4/346.
Signed-off-by: NCarlos R. Mafra <crmafra2@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Valdis.Kletnieks@vt.edu
LKML-Reference: <20090805185334.GA4535@Pilar.aei.mpg.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

While extending perfcounters with BTS hw-tracing, Markus
Metzger managed to trigger this warning:

   [  995.557128] WARNING: at kernel/perf_counter.c:1191 __perf_counter_task_sched_out+0x48/0x6b()

triggers because commit
9f498cc5 (perf_counter: Full
task tracing) removed clearing of tsk->perf_counter_ctxp out
from under ctx->lock which introduced a race (against
perf_lock_task_context).

Move it back and deal with the exit notification by explicitly
passing along the former task context.
Reported-by: NMarkus T Metzger <markus.t.metzger@intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249667341.17467.5.camel@twins>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Based on Peter's comments, make tracepoint sampling generic
just like all the other sampling bits are. This is a rename
with no code changes:

- PERF_SAMPLE_TP_RECORD to PERF_SAMPLE_RAW
- struct perf_tracepoint_record to perf_raw_record

We want the system in place that transport tracepoints raw
samples events into the perf ring buffer to be generalized and
usable by any type of counter.

Reported-by; Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249698400-5441-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Despite that the tracepoint record is always present when the
PERF_SAMPLE_TP_RECORD flag is set, gcc raises a warning,
thinking it might not be initialized:

  kernel/perf_counter.c: In function ‘perf_counter_output’:
  kernel/perf_counter.c:2650: warning: ‘tp’ may be used uninitialized in this function

Then, initialize it to NULL and always check if it's not NULL
before dereference it.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249698400-5441-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

perf tools: callchain: Fix sum of percentages to be 100% by displaying amount of ignored chains in fractal mode

When we filter the callchains below a given percentage, we
ignore them and the end result only shows entries that have an
upper percentage than the filter threshold.

It seems to users then that we have an imbalance in the
percentage, as if the sum inside a profiled branch doesn't
reach 100%.

Since in the past there have been real perf report bugs that
showed the same sypmtom, it would be nice to assure the user
that the data is perfect and trustable and it all sums up to
100.00%.

So fix this by displaying the remaining hits that have been
filtered but without more detail than their amount in each
branches. Example while filtering below 50%:

7.73%  [k] delay_tsc
                |
                |--98.22%-- __const_udelay
                |          |
                |          |--86.37%-- ath5k_hw_register_timeout
                |          |          ath5k_hw_noise_floor_calibration
                |          |          ath5k_hw_reset
                |          |          ath5k_reset
                |          |          ath5k_config
                |          |          ieee80211_hw_config
                |          |          |
                |          |          |--88.53%-- ieee80211_scan_work
                |          |          |          worker_thread
                |          |          |          kthread
                |          |          |          child_rip
                |          |           --11.47%-- [...]
                |           --13.63%-- [...]
                 --1.78%-- [...]
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NFrederic 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: <1249690585-9145-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

If we recorded with -g option to record the callchain, right now
we require a -g option to perf report as well - and people reported
this as unnecessary complication: the user already specified -g
once, no need to require it a second time.

So if the recording includes call-chains, display the callchain by
default from perf report.

( The user can override this default using "-g none" option from
  perf report. )
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NFrederic 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: <1249690585-9145-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When the callchain tree comes to insert an empty backtrace, it
raises a spurious warning about the fact we are inserting an
empty. This is spurious because the radix tree assumes it did
something wrong to reach this state. But it didn't, we just met
an empty callchain that has to be ignored.

This happens occasionally with certain types of call-chain
recordings. If it happens it's a big nuisance as perf report
output starts with thousands of warning lines.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NFrederic 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: <1249690585-9145-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

1. Ignore the -A argument if there is no perf.data file
2. Treat an empty file like a non existent file.

Else, perf will try to read the perf.data header, and fail with
an error.

Treating an empty file like a non-existent file makes sense,
since an interupted (as in SIGKILLed) perf could leave such
files around, and you don't want to annoy the user with errors
for files with no data in it.
Signed-off-by: NPierre Habouzit <pierre.habouzit@intersec.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

While toying with perf, I've noticed that perf record can
easily enter a busy loop when doing something as silly as:

    $ perf record -A ls

Yeah, do_read here really wants to read a known size, not being
able to should die(), not busy-loop ;)

That was the cause for the bug.
Signed-off-by: NPierre Habouzit <pierre.habouzit@intersec.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Stop perf list from displaying tracepoints without an id file,
those are special tracepoints that are not interfaced to
perfcounters so listing them is erroneous and passing them as
events will produce no output.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NJason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

If we have the powerpc perf_counter backend compiled in, but
the cpu we are running on is one where we don't support the
PMU, we currently oops in hw_perf_group_sched_in if we try to
use any counters, because ppmu is NULL in that case, and we
unconditionally dereference ppmu.

This fixes the problem by adding a check if ppmu is NULL at the
beginning of hw_perf_group_sched_in, and also at the beginning
of the other functions that get called from the perf_counter
core, i.e. hw_perf_disable, hw_perf_enable, and
hw_perf_counter_setup.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: benh@kernel.crashing.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We want to use a coherent flag for -S/--stat across all tools,
so free up -S in perf stat.
Signed-off-by: NBrice Goglin <Brice.Goglin@inria.fr>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

perf report: Add debug help for the finding of symbol bugs - show the symtab origin (DSO, build-id, kernel, etc)

Used with perf report --verbose:

[acme@doppio linux-2.6-tip]$ perf report -v | head -16
     5.17%  firefox  /usr/lib64/xulrunner-1.9.1/libxul.so   0x00000000005d8eee f [.] imgContainer::DrawFrameTo(gfxIImageFrame*, gfxIImageFrame*, nsRect&)
     2.56%  firefox  /lib64/libpthread-2.10.1.so            0x0000000000008e02 d [.] __pthread_mutex_lock_internal
     1.94%  firefox  /usr/lib64/xulrunner-1.9.1/libxul.so   0x0000000000d0af8f f [.] SearchTable
     1.75%  firefox  [kernel]                               0xffffffffff60013b k [.] vread_hpet
     1.63%  firefox  /lib64/libpthread-2.10.1.so            0x000000000000a404 d [.] __pthread_mutex_unlock
     1.47%  firefox  /usr/lib64/xulrunner-1.9.1/libmozjs.so 0x00000000000482ea f [.] js_Interpret
     1.42%  firefox  /usr/lib64/xulrunner-1.9.1/libmozjs.so 0x000000000003eda3 f [.] JS_CallTracer
     1.24%  firefox  [kernel]                               0xffffffff8102ca4a k [k] read_hpet
     1.16%  firefox  [kernel]                               0xffffffff810f3dd4 k [k] fget_light
     1.11%  firefox  /usr/lib64/xulrunner-1.9.1/libmozjs.so 0x00000000000567ff f [.] js_TraceObject
     0.98%  firefox  /usr/lib64/firefox-3.5.2/firefox       0x000000000000dd23 b [.] arena_ralloc
[acme@doppio linux-2.6-tip]$

The new field is just after the symbol address. To help in
figuring out symbol resolution bugs.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Brice Goglin reported:

> I can easily sort them by thread id, but I don't know how to match
> my 4 events with each group of 4 lines.

Also report the counter id and the time running/enabled
stats (in case the counter got time-shared).
Reported-by: NBrice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: NBrice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Brice Goglin reported that only the first result from a
multi-counter perf record --stat run is accurate, the
rest looks bogus.

A silly mistake made us re-read the first attribute for
every recorded attribute.
Reported-by: NBrice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: NBrice Goglin <Brice.Goglin@inria.fr>
Cc: paulus@samba.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The callchain fractal mode builds each new total hits in a new
branch of profiling by using the parent's hits of the current
branch plus the hits of the children.

This is wrong, the total hits of a branch should be made of the
sum of every children hits, we must ignore the parent hits in
this scope.

This patch also fixes another mistake with the hit counting.

Now the rates are correct.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: 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>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

perf_counter tools: update perf top manual page to reflect
current implementation.
Signed-off-by: NMike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Pressing any key which is not currently mapped to
functionality, based on startup command line options, displays
currently mapped keys, and prompts for input.

Pressing any unmapped key at the prompt returns the user to
display mode with variables unchanged.  eg, pressing ? <SPACE>
<ESC> etc displays currently available keys, the value of the
variable associated with that key, and prompts.

Pressing same again aborts input.
Signed-off-by: NMike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Reimplement the software counters to deal with fast moving
event sources (such as tracepoints). This means being able
to generate multiple overflows from a single 'event' as well
as support throttling.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

perf_counter tools: Allow perf top top users to switch between weighted and individual counter display

Add [w]eighted hotkey.  Pressing [w] toggles between displaying
weighted total of all counters, and the counter selected via
[E]vent select key.

------------------------------------------------------------------------------
   PerfTop:   90395 irqs/sec  kernel:16.1% [cache-misses/cache-references/instructions],  (all, 4 CPUs)
------------------------------------------------------------------------------

  weight     samples    pcnt         RIP          kernel function
  ______     _______   _____   ________________   _______________

1275408.6      10881 -  5.3% - ffffffff81146f70 : copy_page_c
 553683.4      43569 - 21.3% - ffffffff81146f20 : clear_page_c
  74075.0       6768 -  3.3% - ffffffff81147190 : copy_user_generic_string
  40602.9       7538 -  3.7% - ffffffff81284ba2 : _spin_lock
  26882.1        965 -  0.5% - ffffffff8109d280 : file_ra_state_init

[w]

------------------------------------------------------------------------------
   PerfTop:   91221 irqs/sec  kernel:14.5% [10000Hz cache-misses],  (all, 4 CPUs)
------------------------------------------------------------------------------

  weight     samples    pcnt         RIP          kernel function
  ______     _______   _____   ________________   _______________

            47320.00 - 22.3% - ffffffff81146f20 : clear_page_c
            14261.00 -  6.7% - ffffffff810992f5 : __rmqueue
            11046.00 -  5.2% - ffffffff81146f70 : copy_page_c
             7842.00 -  3.7% - ffffffff81284ba2 : _spin_lock
             7234.00 -  3.4% - ffffffff810aa1d6 : unmap_vmas
Signed-off-by: NMike Galbraith <efault@gmx.de>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

perf top used to have annotation support, but it has bitrotted and
removed.

This patch restores that: it allows the user to select any symbol
in kernel space for source level annotation on the fly, switch
between event counters and alter display variables. When symbol
details are being displayed, stopping annotation reverts to normal.

known keys:
        [d]     select display delay.
        [e]     select display entries (lines).
        [E]     select annotation event counter.
        [f]     select normal display count filter.
        [F]     select annotation display count filter (percentage).
        [qQ]    quit.
        [s]     select annotation symbol and start annotation.
        [S]     stop annotation, revert to normal display.
        [z]     toggle event count zeroing.

Sample:
------------------------------------------------------------------------------
   PerfTop:   16719 irqs/sec  kernel:78.7% [cache-misses/cache-references/instructions/cycles],  (all, 4 CPUs)
------------------------------------------------------------------------------

Showing cache-misses for e1000_clean_rx_irq
  Events  Pcnt (>=3%)
       0  0.0%                  /* adjust length to remove Ethernet CRC */
       0  0.0%                  if (!(adapter->flags2 & FLAG2_CRC_STRIPPING))
       0  0.0%                          length -= 4;
     436  5.0%      f039:       41 f6 84 24 5c 29 00    testb  $0x1,0x295c(%r12)
       0  0.0%      f089:       8b 4d 84                mov    -0x7c(%rbp),%ecx
       0  0.0%      f08c:       48 83 ef 02             sub    $0x2,%rdi
       0  0.0%      f090:       48 83 ee 02             sub    $0x2,%rsi
     811  9.3%      f094:       f3 a4                   rep movsb %ds:(%rsi),%es:(%rdi)
       0  0.0%
       0  0.0%          while (rx_desc->status & E1000_RXD_STAT_DD) {
       0  0.0%      f114:       41 f6 47 0c 01          testb  $0x1,0xc(%r15)
    7226 82.6%      f119:       0f 85 24 fe ff ff       jne    ef43 <e1000_clean_rx_irq+0x84>

Available events:
        0 cache-misses
        1 cache-references
        2 instructions
        3 cycles
Enter details event counter: 2
------------------------------------------------------------------------------
   PerfTop:   15035 irqs/sec  kernel:79.0% [cache-misses/cache-references/instructions/cycles],  (all, 4 CPUs)
------------------------------------------------------------------------------

Showing instructions for e1000_clean_rx_irq
  Events  Pcnt (>=3%)
       0  0.0%                                 int *work_done, int work_to_do)
       0  0.0%  {
     175  0.9%      eebf:       55                      push   %rbp
    1898  9.8%      eec0:       48 89 e5                mov    %rsp,%rbp
       0  0.0%
       0  0.0%          i = rx_ring->next_to_clean;
     140  0.7%      ef0a:       0f b7 41 1a             movzwl 0x1a(%rcx),%eax
     670  3.4%      ef0e:       89 45 ac                mov    %eax,-0x54(%rbp)
       0  0.0%  {
       0  0.0%          memcpy(skb->data + offset, from, len);
      91  0.5%      f07b:       49 8b b6 e8 00 00 00    mov    0xe8(%r14),%rsi
    1153  5.9%      f082:       48 8b b8 e8 00 00 00    mov    0xe8(%rax),%rdi
      42  0.2%      f089:       8b 4d 84                mov    -0x7c(%rbp),%ecx
      14  0.1%      f08c:       48 83 ef 02             sub    $0x2,%rdi
       0  0.0%      f090:       48 83 ee 02             sub    $0x2,%rsi
    1618  8.3%      f094:       f3 a4                   rep movsb %ds:(%rsi),%es:(%rdi)
       0  0.0%
       0  0.0%                  /* return some buffers to hardware, one at a time is too slow */
       0  0.0%                  if (cleaned_count >= E1000_RX_BUFFER_WRITE) {
     867  4.5%      f0e7:       83 7d b0 0f             cmpl   $0xf,-0x50(%rbp)
       0  0.0%
       0  0.0%          while (rx_desc->status & E1000_RXD_STAT_DD) {
      37  0.2%      f114:       41 f6 47 0c 01          testb  $0x1,0xc(%r15)
    4047 20.8%      f119:       0f 85 24 fe ff ff       jne    ef43 <e1000_clean_rx_irq+0x84>
Signed-off-by: NMike Galbraith <efault@gmx.de>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch implements the kernel side support for ftrace event
record sampling.

A new counter sampling attribute is added:

   PERF_SAMPLE_TP_RECORD

which requests ftrace events record sampling. In this case
if a PERF_TYPE_TRACEPOINT counter is active and a tracepoint
fires, we emit the tracepoint binary record to the
perfcounter event buffer, as a sample.

Result, after setting PERF_SAMPLE_TP_RECORD attribute from perf
record:

 perf record -f -F 1 -a -e workqueue:workqueue_execution
 perf report -D

 0x21e18 [0x48]: event: 9
 .
 . ... raw event: size 72 bytes
 .  0000:  09 00 00 00 01 00 48 00 d0 c7 00 81 ff ff ff ff  ......H........
 .  0010:  0a 00 00 00 0a 00 00 00 21 00 00 00 00 00 00 00  ........!......
 .  0020:  2b 00 01 02 0a 00 00 00 0a 00 00 00 65 76 65 6e  +...........eve
 .  0030:  74 73 2f 31 00 00 00 00 00 00 00 00 0a 00 00 00  ts/1...........
 .  0040:  e0 b1 31 81 ff ff ff ff                          .......
.
0x21e18 [0x48]: PERF_EVENT_SAMPLE (IP, 1): 10: 0xffffffff8100c7d0 period: 33

The raw ftrace binary record starts at offset 0020.

Translation:

 struct trace_entry {
	type		= 0x2b = 43;
	flags		= 1;
	preempt_count	= 2;
	pid		= 0xa = 10;
	tgid		= 0xa = 10;
 }

 thread_comm = "events/1"
 thread_pid  = 0xa = 10;
 func	    = 0xffffffff8131b1e0 = flush_to_ldisc()

What will come next?

 - Userspace support ('perf trace'), 'flight data recorder' mode
   for perf trace, etc.

 - The unconditional copy from the profiling callback brings
   some costs however if someone wants no such sampling to
   occur, and needs to be fixed in the future. For that we need
   to have an instant access to the perf counter attribute.
   This is a matter of a flag to add in the struct ftrace_event.

 - Take care of the events recursivity! Don't ever try to record
   a lock event for example, it seems some locking is used in
   the profiling fast path and lead to a tracing recursivity.
   That will be fixed using raw spinlock or recursivity
   protection.

 - [...]

 - Profit! :-)
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Adds possible second part to the assign argument of TP_EVENT().

  TP_perf_assign(
	__perf_count(foo);
	__perf_addr(bar);
  )

Which, when specified make the swcounter increment with @foo instead
of the usual 1, and report @bar for PERF_SAMPLE_ADDR (data address
associated with the event) when this triggers a counter overflow.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Merge reason: Merge up to almost-rc6 to pick up latest perfcounters
              (on which we'll queue up a dependent fix)
Signed-off-by: NIngo Molnar <mingo@elte.hu>

If filter_add_subsystem_pred() fails due to ENOSPC or ENOMEM,
the pred doesn't get freed, while as a side effect it does for
other errors. Make it so the caller always frees the pred for
any error.
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <1249746593.6453.32.camel@tropicana>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Dan Carpenter sent me a fix to prevent pred from being used if
it couldn't be allocated.  I noticed the same problem also
existed for the create_pred() case and added a fix for that.
Reported-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <1249746549.6453.29.camel@tropicana>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6:
  USB: fix oops on disconnect in cdc-acm
  USB: storage: include Prolific Technology USB drive in unusual_devs list
  USB: ftdi_sio: add product_id for Marvell OpenRD Base, Client
  USB: ftdi_sio: add vendor and product id for Bayer glucose meter serial converter cable
  USB: EHCI: fix counting of transaction error retries
  USB: EHCI: fix two new bugs related to Clear-TT-Buffer
  USB: usbfs: fix -ENOENT error code to be -ENODEV
  USB: musb: fix the nop registration for OMAP3EVM
  USB: devio: Properly do access_ok() checks
  USB: pl2303: New vendor and product id

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6:
  Staging: rspiusb: Fix buffer overflow
  staging: add dependencies on PCI for drivers that require it
  Staging: rtl8192su: fix build error
  Staging: rt2870: Revert d44ca7 Removal of kernel_thread() API
  Staging: rt2870: Add USB ID for Linksys, Planex Communications, Belkin

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel: (22 commits)
  drm/i915: Fix read outside array bounds in restoring the SWF10 range.
  drm/i915: Use our own workqueue to avoid wedging the system along with the GPU.
  drm/i915: Add support for dual-channel LVDS on 8xx.
  drm/i915: Return disconnected for SDVO DVI when there's no digital EDID.
  drm/i915: Choose real sdvo output according to result from detection
  drm/i915: Set preferred mode for integrated TV according to TV format
  drm/i915: fix 845G FIFO size & burst length
  drm/i915: fix VGA detect on IGDNG
  drm/i915: Add eDP support on IGDNG mobile chip
  drm/i915: enable DisplayPort support on IGDNG
  drm/i915: Fix channel ending action for DP aux transaction
  drm/i915: fix issue in display pipe setup on IGDNG
  drm/i915: disable VGA plane reliably
  drm/I915: Fix offset to DVO timings in LVDS data
  drm/i915: hdmi detection according by reading edid
  drm/i915: correct self-refresh calculation in "everything off" case
  drm/i915: handle FIFO oversubsription correctly
  drm/i915: FIFO watermark calculation fixes
  drm/i915: ignore lvds on AOpen Mini PC MP-915
  drm/i915: Allow frame buffers up to 4096x4096 on 915/945 class hardware
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: fix balancing oops when invalidate_inode_pages2 returns EBUSY
  Btrfs: correct error-handling zlib error handling
  Btrfs: remove superfluous NULL pointer check in btrfs_rename()
  Btrfs: make sure the async caching thread advances the key
  Btrfs: fix btrfs_remove_from_free_space corner case

* git://git.kernel.org/pub/scm/linux/kernel/git/hch/xfs-icache-races:
  xfs: fix freeing of inodes not yet added to the inode cache
  vfs: add __destroy_inode
  vfs: fix inode_init_always calling convention

usb_buffer_map_sg() may return -1. This will result in a read from
pdx->PixelUrb[frameInfo][-1]
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch adds PCI dependencies to staging drivers that require it.
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This fixes a build error when selecting the rtl8192su driver as a
module.  This has been reported by me, and the opensuse kernel developer
team, and I finally tracked it down.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Staging: rt2870: Revert d44ca7 Removal of kernel_thread() API

The sanity check this patch introduced triggers on shutdown, apparently due to
threads having already exited by the time BUG_ON() is reached.
Signed-off-by: NMike Galbraith <efault@gmx.de>
Cc: Peter Teoh <htmldeveloper@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>