Commit Graph

178 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
247648e374 perf tools: Fix fallback to cplus_demangle() when bfd_demangle() is not available
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>
2009-08-12 14:10:49 +02:00
Arnaldo Carvalho de Melo
94a24752fe perf report: Show the tid too in -D
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>
2009-08-12 14:10:49 +02:00
Arnaldo Carvalho de Melo
2a8083f063 perf record: Fix .tid and .pid fill-in when synthesizing events
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>
2009-08-12 14:10:48 +02:00
Frederic Weisbecker
c0a8865e32 perf tools: callchain: Fix bad rounding of minimum rate
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: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: acme@redhat.com
Cc: peterz@infradead.org
Cc: efault@gmx.de
LKML-Reference: <20090809024235.GA10146@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 13:07:46 +02:00
Mike Galbraith
183f3b0887 perf_counter tools: Fix libbfd detection for systems with libz dependency
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: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1249733655.6929.5.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:47 +02:00
Carlos R. Mafra
c24b513337 perf: "Longum est iter per praecepta, breve et efficax per exempla"
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: Carlos 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: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:46 +02:00
Frederic Weisbecker
25446036cb 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: Ingo Molnar <mingo@elte.hu>
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: <1249690585-9145-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:43 +02:00
Frederic Weisbecker
b1a88349c3 perf tools: callchain: Fix 'perf report' display to be callchain by default
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: Ingo Molnar <mingo@elte.hu>
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: <1249690585-9145-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:42 +02:00
Frederic Weisbecker
b0efe213f8 perf tools: callchain: Fix spurious 'perf report' warnings: ignore empty callchains
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: Ingo Molnar <mingo@elte.hu>
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: <1249690585-9145-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:41 +02:00
Pierre Habouzit
266e0e2198 perf record: Fix the -A UI for empty or non-existent perf.data
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: Pierre Habouzit <pierre.habouzit@intersec.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:40 +02:00
Pierre Habouzit
7eac7e9e72 perf util: Fix do_read() to fail on EOF instead of busy-looping
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: Pierre Habouzit <pierre.habouzit@intersec.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:39 +02:00
Peter Zijlstra
ae07b63f4b perf list: Fix the output to not include tracepoints without an id
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: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:38 +02:00
Brice Goglin
b26bc5a7f8 perf stat: Fix tool option consistency: rename -S/--scale to -c/--scale
We want to use a coherent flag for -S/--stat across all tools,
so free up -S in perf stat.

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:37 +02:00
Arnaldo Carvalho de Melo
94cb9e385d 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: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:36 +02:00
Peter Zijlstra
8f18aec535 perf report: Fix per task mult-counter stat reporting
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: Brice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Brice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:35 +02:00
Peter Zijlstra
1c222bce7d perf tools: Fix multi-counter stat bug caused by incorrect reading of perf.data file header
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: Brice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Brice Goglin <Brice.Goglin@inria.fr>
Cc: paulus@samba.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:34 +02:00
Frederic Weisbecker
1953287bfe perf tools: Fix call-chain cumul hit based sub-total (fractal mode)
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: Frederic 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: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:33 +02:00
Mike Galbraith
8361798348 perf top: Update man page
perf_counter tools: update perf top manual page to reflect
current implementation.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:32 +02:00
Mike Galbraith
091bd2e993 perf top: Improve interactive key handling
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: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:31 +02:00
Mike Galbraith
46ab976443 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: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:30 +02:00
Mike Galbraith
923c42c199 perf_counter tools: Fix/resurrect perf top annotation in a simple interactive form
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: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:29 +02:00
Frederic Weisbecker
f413cdb80c perf_counter: Fix/complete ftrace event records sampling
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: Frederic 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: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:53:48 +02:00
Peter Zijlstra
9424edc2da perf: Auto-detect libelf
Adds autodetection for libelf as well, and simplifies the
libbfd code. Furthermore, fail make with an error when libelf
is not found and warn about the lack of libbfd.

Also provide an option to build a 32bit version even though you
might be running a 64bit kernel.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-06 20:25:13 +02:00
Arnaldo Carvalho de Melo
4d1e00a8af perf symbol: Fix symbol parsing in certain cases: use the build-id as a symlink
In some cases distros have binaries and debuginfo in weird places:

[root@doppio tuna]# ls -la /usr/lib64/{xulrunner-1.9.1/xulrunner-stub,firefox-3.5.2/firefox}
-rwxr-xr-x 1 root root 90024 2009-08-03 19:45 /usr/lib64/firefox-3.5.2/firefox
-rwxr-xr-x 1 root root 90024 2009-08-03 18:23 /usr/lib64/xulrunner-1.9.1/xulrunner-stub
[root@doppio tuna]# sha1sum /usr/lib64/{xulrunner-1.9.1/xulrunner-stub,firefox-3.5.2/firefox}
19a858077d263d5de22c9c5da250d3e4396ae739  /usr/lib64/xulrunner-1.9.1/xulrunner-stub
19a858077d263d5de22c9c5da250d3e4396ae739  /usr/lib64/firefox-3.5.2/firefox
[root@doppio tuna]# rpm -qf /usr/lib64/{xulrunner-1.9.1/xulrunner-stub,firefox-3.5.2/firefox}
xulrunner-1.9.1.2-1.fc11.x86_64
firefox-3.5.2-2.fc11.x86_64
[root@doppio tuna]# ls -la /usr/lib/debug/{usr/lib64/xulrunner-1.9.1/xulrunner-stub,usr/lib64/firefox-3.5.2/firefox}.debug
ls: cannot access /usr/lib/debug/usr/lib64/firefox-3.5.2/firefox.debug: No such file or directory
-rwxr-xr-x 1 root root 403608 2009-08-03 18:22 /usr/lib/debug/usr/lib64/xulrunner-1.9.1/xulrunner-stub.debug

Seemingly we don't have a .symtab when we actually can find it
if we use the .note.gnu.build-id ELF section put in place by
some distros. Use it and find the symbols we need.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-06 20:24:37 +02:00
Arnaldo Carvalho de Melo
386c0b702b perf report: Add missing command line options to man page
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090805130453.GC10688@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-05 16:09:28 +02:00
Peter Zijlstra
2cdbc46d7b perf: Auto-detect libbfd
Since the C++ demangling isn't needed for everybody and
bfd/iberty aren't widely/easily available on all machines, make
it optional.

It also allows you to forcefully disable demangling by using
NO_DEMANGLE=1 and otherwise tries to detect libbfd/libiberty
combinations that result in a compiling demangler.

Reported-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
LKML-Reference: <20090801082048.GX12579@kernel.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-05 14:12:08 +02:00
Pekka Enberg
114cfab222 perf report: Make --sort comm,dso,symbol the default
If you're doing performance testing, you're interested in the
symbols anyway so lets make "--sort comm,dso,symbol" the
default sort option.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: acme@redhat.com
LKML-Reference: <1249467921-10450-1-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-05 13:16:04 +02:00
Roel Kluin
7e030655dd perf: Fix read buffer overflow
Check whether index is within bounds before testing the element.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: a.p.zijlstra@chello.nl
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A757BCF.40101@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-04 11:09:56 +02:00
Arnaldo Carvalho de Melo
59b9005692 perf top: Add mwait_idle_with_hints to skip_symbols[]
We skip the display of idle routine related symbols because
they are typically rather erratic and confusing: they depend
on the IRQ rate or sometimes they dominate the profile if
they are polling based.

Add mwait_idle_with_hints too, this is one of the idle
routines on x86.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-02 13:58:16 +02:00
Stoyan Gaydarov
9b30a26bf3 perf tools: Fix faulty check
This patch fixes a spelling error that has resulted from copy
and pasting. The location of the error was found using a
semantic patch but the semantic patch was not trying to find
these errors. After looking things over it seemed logical that
this change was needed. Please review it and then include the
patch if it is in fact the correct change.

Signed-off-by: Stoyan Gaydarov <sgayda2@uiuc.edu>
Signed-off-by: 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: <1248949529-20891-1-git-send-email-sgayda2@uiuc.edu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-02 13:47:59 +02:00
Peter Zijlstra
27d028de64 perf report: Update for the new FORK/EXIT events
Since FORK is now also issued for threads, detect those by
comparing the parent and child PID.

Teach it about EXIT events and ignore them.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-02 13:47:57 +02:00
Ingo Molnar
2d1b6949d2 perf_counter tools: Fix link errors with older toolchains
On older distros (F8 for example) the perf build could fail
with such missing symbols:

    LINK perf
/usr/lib/gcc/x86_64-redhat-linux/4.3.2/../../../../lib64/libbfd.a(bfd.o): In function `bfd_demangle':
(.text+0x2b3): undefined reference to `cplus_demangle'
/usr/lib/gcc/x86_64-redhat-linux/4.3.2/../../../../lib64/libbfd.a(bfd.o): In function `bfd_demangle':

Link in -liberty too.

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>
2009-08-01 13:15:36 +02:00
Linus Torvalds
3c3301083e Merge branch 'perf-counters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-perf
* 'perf-counters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-perf: (31 commits)
  perf_counter tools: Give perf top inherit option
  perf_counter tools: Fix vmlinux symbol generation breakage
  perf_counter: Detect debugfs location
  perf_counter: Add tracepoint support to perf list, perf stat
  perf symbol: C++ demangling
  perf: avoid structure size confusion by using a fixed size
  perf_counter: Fix throttle/unthrottle event logging
  perf_counter: Improve perf stat and perf record option parsing
  perf_counter: PERF_SAMPLE_ID and inherited counters
  perf_counter: Plug more stack leaks
  perf: Fix stack data leak
  perf_counter: Remove unused variables
  perf_counter: Make call graph option consistent
  perf_counter: Add perf record option to log addresses
  perf_counter: Log vfork as a fork event
  perf_counter: Synthesize VDSO mmap event
  perf_counter: Make sure we dont leak kernel memory to userspace
  perf_counter tools: Fix index boundary check
  perf_counter: Fix the tracepoint channel to perfcounters
  perf_counter, x86: Extend perf_counter Pentium M support
  ...
2009-07-22 11:41:56 -07:00
Mike Galbraith
0fdc7e67dd perf_counter tools: Give perf top inherit option
Currently, perf top -p only tracks the pid provided, which isn't very useful
for watching forky loads, so give it an inherit option.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248165036.9795.10.camel@marge.simson.net>
2009-07-22 18:05:58 +02:00
Mike Galbraith
d20ff6bd6b perf_counter tools: Fix vmlinux symbol generation breakage
vmlinux meets the criteria for symbol adjustment, which breaks vmlinux generated symbols.
Fix this by exempting vmlinux.  This is a bit fragile in that someone could change the
kernel dso's name, but currently that name is also hardwired.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248091298.18702.18.camel@marge.simson.net>
2009-07-22 18:05:58 +02:00
Jason Baron
5beeded123 perf_counter: Detect debugfs location
If "/sys/kernel/debug" is not a debugfs mount point, search for the debugfs
filesystem in /proc/mounts, but also allows the user to specify
'--debugfs-dir=blah' or set the environment variable: 'PERF_DEBUGFS_DIR'

Signed-off-by: Jason Baron <jbaron@redhat.com>
[ also made it probe "/debug" by default ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090721181629.GA3094@redhat.com>
2009-07-22 18:05:57 +02:00
Jason Baron
f6bdafef2a perf_counter: Add tracepoint support to perf list, perf stat
Add support to 'perf list' and 'perf stat' for kernel tracepoints. The
implementation creates a 'for_each_subsystem' and 'for_each_event' for
easy iteration over the tracepoints.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <426129bf9fcc8ee63bb094cf736e7316a7dcd77a.1248190728.git.jbaron@redhat.com>
2009-07-22 18:05:57 +02:00
Arnaldo Carvalho de Melo
28ac909b49 perf symbol: C++ demangling
[acme@doppio ~]$ perf report -s comm,dso,symbol -C firefox -d /usr/lib64/xulrunner-1.9.1/libxul.so | grep :: | head
     2.21%  [.] nsDeque::Push(void*)
     1.78%  [.] GraphWalker::DoWalk(nsDeque&)
     1.30%  [.] GCGraphBuilder::AddNode(void*, nsCycleCollectionParticipant*)
     1.27%  [.] XPCWrappedNative::CallMethod(XPCCallContext&, XPCWrappedNative::CallMode)
     1.18%  [.] imgContainer::DrawFrameTo(gfxIImageFrame*, gfxIImageFrame*, nsRect&)
     1.13%  [.] nsDeque::PopFront()
     1.11%  [.] nsGlobalWindow::RunTimeout(nsTimeout*)
     0.97%  [.] nsXPConnect::Traverse(void*, nsCycleCollectionTraversalCallback&)
     0.95%  [.] nsJSEventListener::cycleCollection::Traverse(void*, nsCycleCollectionTraversalCallback&)
     0.95%  [.] nsCOMPtr_base::~nsCOMPtr_base()
[acme@doppio ~]$

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Suggested-by: Clark Williams <williams@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090720171412.GB10410@ghostprotocols.net>
2009-07-22 18:05:57 +02:00
Arjan van de Ven
dfe5a50461 perf: avoid structure size confusion by using a fixed size
for some reason, this structure gets compiled as 36 bytes in some files
(the ones that alloacte it) but 40 bytes in others (the ones that use it).
The cause is an off_t type that gets a different size in different
compilation units for some yet-to-be-explained reason.

But the effect is disasterous; the size/offset members of the struct
are at different offsets, and result in mostly complete garbage.
The parser in perf is so robust that this all gets hidden, and after
skipping an certain amount of samples, it recovers.... so this bug
is not normally noticed.

.... except when you want every sample to be exact.

Fix this by just using an explicitly sized type.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4A655917.9080504@linux.intel.com>
2009-07-22 18:05:57 +02:00
Anton Blanchard
a0541234f8 perf_counter: Improve perf stat and perf record option parsing
perf stat and perf record currently look for all options on the command
line. This can lead to some confusion:

# perf stat ls -l
  Error: unknown switch `l'

While we can work around this by adding '--' before the command, the git
option parsing code can stop at the first non option:

# perf stat ls -l
 Performance counter stats for 'ls -l':
....

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090722130412.GD9029@kryten>
2009-07-22 18:05:56 +02:00
Peter Zijlstra
7f453c24b9 perf_counter: PERF_SAMPLE_ID and inherited counters
Anton noted that for inherited counters the counter-id as provided by
PERF_SAMPLE_ID isn't mappable to the id found through PERF_RECORD_ID
because each inherited counter gets its own id.

His suggestion was to always return the parent counter id, since that
is the primary counter id as exposed. However, these inherited
counters have a unique identifier so that events like
PERF_EVENT_PERIOD and PERF_EVENT_THROTTLE can be specific about which
counter gets modified, which is important when trying to normalize the
sample streams.

This patch removes PERF_EVENT_PERIOD in favour of PERF_SAMPLE_PERIOD,
which is more useful anyway, since changing periods became a lot more
common than initially thought -- rendering PERF_EVENT_PERIOD the less
useful solution (also, PERF_SAMPLE_PERIOD reports the more accurate
value, since it reports the value used to trigger the overflow,
whereas PERF_EVENT_PERIOD simply reports the requested period changed,
which might only take effect on the next cycle).

This still leaves us PERF_EVENT_THROTTLE to consider, but since that
_should_ be a rare occurrence, and linking it to a primary id is the
most useful bit to diagnose the problem, we introduce a
PERF_SAMPLE_STREAM_ID, for those few cases where the full
reconstruction is important.

[Does change the ABI a little, but I see no other way out]

Suggested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248095846.15751.8781.camel@twins>
2009-07-22 18:05:56 +02:00
Peter Zijlstra
1d2f37945d Merge commit 'tip/perfcounters/core' into perf-counters-for-linus 2009-07-22 18:05:48 +02:00
Anton Blanchard
1483b19f8f perf_counter: Make call graph option consistent
perf record uses -g for logging call graph data but perf report
uses -c to print call graph data. Be consistent and use -g
everywhere for call graph data.

Also update the help text to reflect the current default -
fractal,0.5

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090716104817.803604373@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-18 11:21:33 +02:00
Anton Blanchard
4bba828dd9 perf_counter: Add perf record option to log addresses
Add the -d or --data option to log event addresses (eg page
faults).

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090716104817.697698033@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-18 11:21:32 +02:00
Anton Blanchard
11b5f81e1b perf_counter: Synthesize VDSO mmap event
perf record synthesizes mmap events for the running process.
Right now it just catches file mappings, but we can check for
the vdso symbol and add that too.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090716104817.517264409@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-18 11:21:30 +02:00
Roel Kluin
23cdb5d517 perf_counter tools: Fix index boundary check
Keep index within event_type_descriptors[]

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
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: <4A5A7F0B.4070106@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-13 10:58:28 +02:00
Arnaldo Carvalho de Melo
e3d7e183dc perf report: Introduce -n/--show-nr-samples
[acme@doppio pahole]$ perf report -ns comm,dso,symbol -d /lib64/libc-2.10.1.so -C pahole | head -17
    21.94%      32101  [.] _int_malloc
    20.10%      29402  [.] __GI_strcmp
    16.77%      24533  [.] __tsearch
    12.61%      18450  [.] malloc_consolidate
     6.42%       9394  [.] _int_free
     6.28%       9191  [.] __tfind
     4.56%       6678  [.] __GI___libc_free
     4.46%       6520  [.] _IO_vfprintf_internal
     2.59%       3786  [.] __malloc
     1.17%       1716  [.] __GI_memcpy
[acme@doppio pahole]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1247325517-12272-5-git-send-email-acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-11 19:20:27 +02:00
Arnaldo Carvalho de Melo
a25e46c463 perf_counter tools: PLT info is stripped in -debuginfo packages
So we need to get the richer .symtab from the debuginfo
packages but the PLT info from the original DSO where we have
just the leaner .dynsym symtab.

Example:

| [acme@doppio pahole]$ perf report --sort comm,dso,symbol > before
| [acme@doppio pahole]$ perf report --sort comm,dso,symbol > after
| [acme@doppio pahole]$ diff -U1 before after
| --- before	2009-07-11 11:04:22.688595741 -0300
| +++ after	2009-07-11 11:04:33.380595676 -0300
| @@ -80,3 +80,2 @@
|       0.07%  pahole ./build/pahole              [.] pahole_stealer
| -     0.06%  pahole /usr/lib64/libdw-0.141.so   [.] 0x00000000007140
|       0.06%  pahole /usr/lib64/libdw-0.141.so   [.] __libdw_getabbrev
| @@ -91,2 +90,3 @@
|       0.06%  pahole [kernel]                    [k] free_hot_cold_page
| +     0.06%  pahole /usr/lib64/libdw-0.141.so   [.] tfind@plt
|       0.05%  pahole ./build/libdwarves.so.1.0.0 [.] ftype__add_parameter
| @@ -242,2 +242,3 @@
|       0.01%  pahole [kernel]                    [k] account_group_user_time
| +     0.01%  pahole /usr/lib64/libdw-0.141.so   [.] strlen@plt
|       0.01%  pahole ./build/pahole              [.] strcmp@plt
| [acme@doppio pahole]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1247325517-12272-4-git-send-email-acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-11 19:20:26 +02:00
Arnaldo Carvalho de Melo
021191b35c perf report: Make the output more compact
When we filter by column content we may end up with a column
that has the same value for all the lines. So remove that
column and tell its unique value on the top, as a comment.

Example:

  [acme@doppio pahole]$  perf report --sort comm,dso,symbol -d ./build/libdwarves.so.1.0.0 -C pahole | head -15
  # dso: ./build/libdwarves.so.1.0.0
  # comm: pahole
  # Samples: 58409
  #
  # Overhead  Symbol
  # ........  ......
  #
      20.93%  [.] tag__recode_dwarf_type
      14.94%  [.] namespace__recode_dwarf_types
      10.38%  [.] cu__table_add_tag
       6.69%  [.] __die__process_tag
       5.05%  [.] die__process_function
       4.70%  [.] list__for_all_tags
       3.68%  [.] tag__init
       3.48%  [.] die__create_new_parameter
  [acme@doppio pahole]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1247325517-12272-3-git-send-email-acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-11 19:20:26 +02:00
Arnaldo Carvalho de Melo
27d0fd410c strlist: Introduce strlist__entry and strlist__nr_entries methods
The strlist__entry method allows accessing strlists like an
array, will be used in the 'perf report' to access the first
entry.

We now keep the nr_entries so that we can check if we have just
one entry, will be used in 'perf report' to improve the output
by showing just at the top when we have just, say, one DSO.

While at it use nr_entries to optimize strlist__is_empty by not
using the far more costly rb_first based implementation.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1247325517-12272-2-git-send-email-acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-11 19:20:25 +02:00