/me dons the brown paper bag.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Draining the BTS buffer on a buffer overflow interrupt takes too
long resulting in a kernel lockup when tracing the kernel.

Restructure perf_counter sampling into sample creation and sample
output.

Prepare a single reference sample for BTS sampling and update the
from and to address fields when draining the BTS buffer. Drain the
entire BTS buffer between a single perf_output_begin() /
perf_output_end() pair.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090915130023.A16204@sedona.ch.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

perf sched record passes unparsed args on to perf record, so
specifying an output file via perf sched record -o FILE (cmd) just
works.  Ergo, provide an option to specify input file as well.

Also add the missing 'map' command to help.
Signed-off-by: NMike Galbraith <efault@gmx.de>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1253254944.20589.11.camel@marge.simson.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Sample timestamp and cpu just like the -R option.

Before:
            init-0     [-01] 1266874889.17179869184709551615: irq_handler_entry: irq=18 handler=eth0
            init-0     [-01] 1266874889.17179869184709551615: irq_handler_entry: irq=18 handler=eth0
            init-0     [-01] 1266874889.17179869184709551615: irq_handler_entry: irq=1 handler=i8042
            init-0     [-01] 1266874889.17179869184709551615: irq_handler_entry: irq=18 handler=eth0
            init-0     [-01] 1266874889.17179869184709551615: irq_handler_entry: irq=1 handler=i8042

After:
            init-0     [001]  7364.568965353: irq_handler_entry: irq=18 handler=eth0
            init-0     [001]  7365.530226877: irq_handler_entry: irq=1 handler=i8042
            init-0     [001]  7365.542831563: irq_handler_entry: irq=18 handler=eth0
            init-0     [001]  7365.644156299: irq_handler_entry: irq=18 handler=eth0
            init-0     [001]  7365.694556201: irq_handler_entry: irq=18 handler=eth0
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4AB1F827.8040905@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The name length of some trace events is longer than 30, like
sys_enter_sched_get_priority_max and
ext4_mb_discard_preallocations.

Passing those events to perf-record will fail, try:

  # ./perf record -f -e syscalls:sys_enter_sched_get_priority_max -F 1 -a
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4AB1F4AB.7050205@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

get_tracing_file() should be paired with put_tracing_file().
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4AB1F48F.4070807@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

For 'perf sched map' output, determine max_cpu automatically,
instead of the static default of 15.

[ v2: use sysconf() pointed out by Arjan van de Ven <arjan@infradead.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: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

I noticed that perf-record continues profiling itself after the
child terminated and we're draining the buffer.

This can cause a _lot_ of overhead with --all recording - we keep
and keep recording, which produces new and new events.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Currently we wake the mmap() consumer once every PAGE_SIZE of data
and/or once event wakeup_events when specified.

For high speed sampling this results in too many wakeups wrt. the
buffer size, hence change this.

We move the default wakeup limit to 1/4-th the buffer size, and
provide for means to manually specify this limit.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We can have swcounter events that contribute more than a single
count per event, when used with a non-zero period, those can
generate multiple events, which is when we need throttling.

However, swcounter that contribute only a single count per event
can only come as fast as we can run code, hence don't throttle
them.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This prints a textual context-switching outline of workload
captured via perf sched record.

For example, on a 16 CPU box it outputs:

   N1  O1  .   .   .   S1  .   .   .   B0  .  *I0  C1  .   M1  .    23002.773423 secs
   N1  O1  .  *Q0  .   S1  .   .   .   B0  .   I0  C1  .   M1  .    23002.773423 secs
   N1  O1  .   Q0  .   S1  .   .   .   B0  .  *R1  C1  .   M1  .    23002.773485 secs
   N1  O1  .   Q0  .   S1  .  *S0  .   B0  .   R1  C1  .   M1  .    23002.773478 secs
  *L0  O1  .   Q0  .   S1  .   S0  .   B0  .   R1  C1  .   M1  .    23002.773523 secs
   L0  O1  .  *.   .   S1  .   S0  .   B0  .   R1  C1  .   M1  .    23002.773531 secs
   L0  O1  .   .   .   S1  .   S0  .   B0  .   R1  C1 *T1  M1  .    23002.773547 secs T1 => irqbalance:2089
   L0  O1  .   .   .   S1  .   S0  .  *P0  .   R1  C1  T1  M1  .    23002.773549 secs
  *N1  O1  .   .   .   S1  .   S0  .   P0  .   R1  C1  T1  M1  .    23002.773566 secs
   N1  O1  .   .   .  *J0  .   S0  .   P0  .   R1  C1  T1  M1  .    23002.773571 secs
   N1  O1  .   .   .   J0  .   S0 *B0  P0  .   R1  C1  T1  M1  .    23002.773592 secs
   N1  O1  .   .   .   J0  .  *U0  B0  P0  .   R1  C1  T1  M1  .    23002.773582 secs
   N1  O1  .   .   .  *S1  .   U0  B0  P0  .   R1  C1  T1  M1  .    23002.773604 secs
   N1  O1  .   .   .   S1  .   U0  B0 *.   .   R1  C1  T1  M1  .    23002.773615 secs
   N1  O1  .   .   .   S1  .   U0  B0  .   .  *K0  C1  T1  M1  .    23002.773631 secs
   N1  O1  .  *M0  .   S1  .   U0  B0  .   .   K0  C1  T1  M1  .    23002.773624 secs
   N1  O1  .   M0  .   S1  .   U0 *.   .   .   K0  C1  T1  M1  .    23002.773644 secs
   N1  O1  .   M0  .   S1  .   U0  .   .   .  *R1  C1  T1  M1  .    23002.773662 secs
   N1  O1  .   M0  .   S1  .  *.   .   .   .   R1  C1  T1  M1  .    23002.773648 secs
   N1  O1  .  *.   .   S1  .   .   .   .   .   R1  C1  T1  M1  .    23002.773680 secs
   N1  O1  .   .   .  *L0  .   .   .   .   .   R1  C1  T1  M1  .    23002.773717 secs
  *N0  O1  .   .   .   L0  .   .   .   .   .   R1  C1  T1  M1  .    23002.773709 secs
  *N1  O1  .   .   .   L0  .   .   .   .   .   R1  C1  T1  M1  .    23002.773747 secs

Columns stand for individual CPUs, from CPU0 to CPU15, and the
two-letter shortcuts stand for tasks that are running on a CPU.

'*' denotes the CPU that had the event.

A dot signals an idle CPU.

New tasks are assigned new two-letter shortcuts - when they occur
first they are printed. In the above example 'T1' stood for irqbalance:

      T1 => irqbalance:2089

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: NIngo Molnar <mingo@elte.hu>

Peter noticed that we have 3 ways of referring to the idle thread:

 [idle]:0
 swapper:0
 swapper-0

Standardize on 'swapper:0'.
Reported-by: NPeter 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: NIngo Molnar <mingo@elte.hu>

Use 'perf sched latency' to track the current task based on
context-switch events, and flag the cases where there's some
impossible transition: such as a PID being switched out that
was not switched in.

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: NIngo Molnar <mingo@elte.hu>

Output such lost event and state machine weirdness stats:

   TOTAL:                |  14974.910 ms |    46384 |
  ---------------------------------------------------
   INFO: 8.865% lost events (19132 out of 215819, in 8 chunks)
   INFO: 0.198% state machine bugs (49 out of 24708) (due to lost events?)

And increase buffering to -m 1024 (4 MB) by default. Since we
use output multiplexing that kind of space is needed.

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: NIngo Molnar <mingo@elte.hu>

This allows more precise 'perf sched latency' output:

 ---------------------------------------------------------------------------------------
  Task                  |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
 ---------------------------------------------------------------------------------------
  ksoftirqd/0-4         |    0.010 ms |        2 | avg:    2.476 ms | max:    2.977 ms |
  perf-12328            |   15.844 ms |       66 | avg:    1.118 ms | max:    9.979 ms |
  bdi-default-235       |    0.009 ms |        1 | avg:    0.998 ms | max:    0.998 ms |
  events/1-8            |    0.020 ms |        2 | avg:    0.998 ms | max:    0.998 ms |
  events/0-7            |    0.018 ms |        2 | avg:    0.992 ms | max:    0.996 ms |
  sleep-12329           |    0.742 ms |        3 | avg:    0.906 ms | max:    2.289 ms |
  sshd-12122            |    0.163 ms |        2 | avg:    0.283 ms | max:    0.562 ms |
  loop-getpid-lon-12322 | 1023.636 ms |       69 | avg:    0.208 ms | max:    5.996 ms |
  loop-getpid-lon-12321 | 1038.638 ms |        5 | avg:    0.073 ms | max:    0.171 ms |
  migration/1-5         |    0.000 ms |        1 | avg:    0.006 ms | max:    0.006 ms |
 ---------------------------------------------------------------------------------------
  TOTAL:                | 2079.078 ms |      153 |
 -------------------------------------------------

Also, streamline the code a bit more, add asserts for various state
machine failures (they should be debugged if they occur) and fix
a few odd ends.

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: NIngo Molnar <mingo@elte.hu>

Often it's useful to know the PID of the task as well - print it
out too.

( While at it, reformat the output to be a bit more
  paste-into-commit-logs friendly. )

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: NIngo Molnar <mingo@elte.hu>

Before:

  -----------------------------------------------------------------------------------
   Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
  -----------------------------------------------------------------------------------
   perf              |4853313.251 ms |       10 | avg:    0.046 ms | max:    0.337 ms |
   flush-8:0         |2426659.202 ms |        5 | avg:    0.015 ms | max:    0.016 ms |
   sleep             |485331.966 ms |        1 | avg:    0.012 ms | max:    0.012 ms |
   ksoftirqd/1       |485331.320 ms |        1 | avg:    0.005 ms | max:    0.005 ms |
  -----------------------------------------------------------------------------------
   TOTAL:            |8250635.739 ms |       17 |
  ---------------------------------------------

After:

  -----------------------------------------------------------------------------------
   Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
  -----------------------------------------------------------------------------------
   perf              |    0.206 ms |       10 | avg:    0.046 ms | max:    0.337 ms |
   flush-8:0         |    2.680 ms |        5 | avg:    0.015 ms | max:    0.016 ms |
   sleep             |    0.662 ms |        1 | avg:    0.012 ms | max:    0.012 ms |
   ksoftirqd/1       |    0.015 ms |        1 | avg:    0.005 ms | max:    0.005 ms |
  -----------------------------------------------------------------------------------
   TOTAL:            |    3.563 ms |       17 |
  ---------------------------------------------

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: NIngo Molnar <mingo@elte.hu>

Finish the -M/--multiplex option implementation:

 - separate it out from group_fd

 - correctly set it via the ioctl and dont mmap counters that
   are multiplexed

 - modify the perf record event loop to deal with buffer-less
   counters.

 - remove the -g option from perf sched record

 - account for unordered events in perf sched latency

 - (add -f to perf sched record to ease measurements)

 - skip idle threads (pid==0) in latency output

The result is better latency output by 'perf sched latency':

 -----------------------------------------------------------------------------------
  Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
 -----------------------------------------------------------------------------------
  ksoftirqd/8       |    0.071 ms |        2 | avg:    0.458 ms | max:    0.913 ms |
  at-spi-registry   |    0.609 ms |       19 | avg:    0.013 ms | max:    0.023 ms |
  perf              |    3.316 ms |       16 | avg:    0.013 ms | max:    0.054 ms |
  Xorg              |    0.392 ms |       19 | avg:    0.011 ms | max:    0.018 ms |
  sleep             |    0.537 ms |        2 | avg:    0.009 ms | max:    0.009 ms |
 -----------------------------------------------------------------------------------
  TOTAL:            |    4.925 ms |       58 |
 ---------------------------------------------

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: NIngo Molnar <mingo@elte.hu>

Currently it's possible to meet such too high latency results
with 'perf sched latency'.

 -----------------------------------------------------------------------------------
 Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
 -----------------------------------------------------------------------------------
 xfce4-panel       |    0.222 ms |        2 | avg: 4718.345 ms | max: 9436.493 ms |
 scsi_eh_3         |    3.962 ms |       36 | avg:   55.957 ms | max: 1977.829 ms |

The origin is on traces that are sometimes badly serialized across cpus.
For example the raw traces that raised such results for xfce4-panel:

(1)          [init]-0     [000]  1494.663899990: sched_switch: task swapper:0 [140] (R) ==> xfce4-panel:4569 [120]
(2)     xfce4-panel-4569  [000]  1494.663928373: sched_switch: task xfce4-panel:4569 [120] (S) ==> swapper:0 [140]
(3)            Xorg-4276  [001]  1494.663860125: sched_wakeup: task xfce4-panel:4569 [120] success=1 [000]
(4)            Xorg-4276  [001]  1504.098252756: sched_wakeup: task xfce4-panel:4569 [120] success=1 [000]
(5)            perf-5219  [000]  1504.100353302: sched_switch: task perf:5219 [120] (S) ==> xfce4-panel:4569 [120]

The traces are processed in the order they arrive. Then in (2),
xfce4-panel sleeps, it is first waken up in (3) and eventually
scheduled in (5).

The latency reported is then 1504 - 1495 = 9 secs, as reported by perf
sched. But this is wrong, we are confident in the fact the traces are
nicely serialized while we should actually more trust the timestamps.

If we reorder by timestamps we get:

(1)            Xorg-4276  [001]  1494.663860125: sched_wakeup: task xfce4-panel:4569 [120] success=1 [000]
(2)          [init]-0     [000]  1494.663899990: sched_switch: task swapper:0 [140] (R) ==> xfce4-panel:4569 [120]
(3)     xfce4-panel-4569  [000]  1494.663928373: sched_switch: task xfce4-panel:4569 [120] (S) ==> swapper:0 [140]
(4)            Xorg-4276  [001]  1504.098252756: sched_wakeup: task xfce4-panel:4569 [120] success=1 [000]
(5)            perf-5219  [000]  1504.100353302: sched_switch: task perf:5219 [120] (S) ==> xfce4-panel:4569 [120]

Now the trace make more sense, xfce4-panel is sleeping. Then it is
woken up in (1), scheduled in (2)
It goes to sleep in (3), woken up in (4) and scheduled in (5).

Now, latency captured between (1) and (2) is of 39 us.
And between (4) and (5) it is 2.1 ms.

Such pattern of bad serializing is the origin of the high latencies
reported by perf sched.

Basically, we need to check whether wake up time is higher than
schedule out time. If it's not the case, we need to tag the current
work atom as invalid.

Beside that, we may need to work later on a better ordering of the
traces given by the kernel.

After this patch:

xfce4-session     |    0.221 ms |        1 | avg:    0.538 ms | max:    0.538 ms |
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add an option to multiplex counters output in the channel of
the group leader, ie: the first counter opened:

	-M --multiplex

The effect is better serialized samples. This is especially
useful for tracepoint samples that need to be well serialized
for their post-processing.

Also make use of this option in 'perf sched'.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This allows more precise tracking of how the scheduler accounts
(and acts upon) a task having spent N nanoseconds of CPU time.

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: NIngo Molnar <mingo@elte.hu>

Alias 'perf sched trace' to 'perf trace', for workflow completeness.

Add a bit of documentation for perf sched.

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: NIngo Molnar <mingo@elte.hu>

Before:

  $ perf sched record -f sleep 1
  Error: failed to mmap with 1 (Operation not permitted)

After:

  $ perf sched record -f sleep 1
  [ perf record: Captured and wrote 0.095 MB perf.data (~4161 samples) ]

Note, this is only allowed if perfcounter_paranoid is set to
the most permissive (non-default) value of -1.

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: NIngo Molnar <mingo@elte.hu>

Implement the 'perf sched record' subcommand that adds a
default list of events, turns on raw sampling and system-wide
tracing and passes off the rest of the command to perf record.

This is more convenient than having to specify the events all
the time.

Before:

 $ perf record -a -R -e sched:sched_switch:r -e sched:sched_stat_wait:r -e sched:sched_stat_sleep:r -e sched:sched_stat_iowait:r -e sched:sched_process_exit:r -e sched:sched_process_fork:r -e sched:sched_wakeup:r -e sched:sched_migrate_task:r -c 1 sleep 1

After:

 $ perf sched record -f sleep 1

Also fix an assumption in the event string parser that assumed
that strings passed in can be modified. (In this case they wont
be as they come from a readonly constant section.)
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use a sort list for thread atoms insertion as well - instead of
hardcoded for PID.

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: NIngo Molnar <mingo@elte.hu>

- Rename 'latency' field/variable names to the better 'atom' ones

 - Reduce the number of #include lines and consolidate them

 - Gather file scope variables at the top of the file

 - Remove unused bits

No change in functionality.

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: NIngo Molnar <mingo@elte.hu>

Separate the option parsing cleanly and add two variants:

 - 'perf sched latency' (can be abbreviated via 'perf sched lat')
 - 'perf sched replay'  (can be abbreviated via 'perf sched rep')

Also add a repeat count option to replay and add a separation
set of options for replay.

Do the sorting setup only in the latency sub-command.

Display separate help screens for 'perf sched' and
'perf sched replay -h' - i.e. further separation of the
sub-commands.

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: NIngo Molnar <mingo@elte.hu>

Implement multidimensional sorting on perf sched so that
you can sort either by number of switches, latency average,
latency maximum, runtime.

perf sched -l -s avg,max  (this is the default)

-----------------------------------------------------------------------------------
 Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
-----------------------------------------------------------------------------------
 gnome-power-man   |    0.113 ms |        1 | avg: 4998.531 ms | max: 4998.531 ms |
 xfdesktop         |    1.190 ms |        7 | avg:  136.475 ms | max:  940.933 ms |
 xfce-mcs-manage   |    2.194 ms |       22 | avg:   38.534 ms | max:  735.174 ms |
 notification-da   |    2.749 ms |       31 | avg:   27.436 ms | max:  731.791 ms |
 xfce4-session     |    3.343 ms |       28 | avg:   26.796 ms | max:  734.891 ms |
 xfwm4             |    3.159 ms |       22 | avg:   12.406 ms | max:  241.333 ms |
 xchat             |   42.789 ms |      214 | avg:   11.886 ms | max:  100.349 ms |
 xfce4-terminal    |    5.386 ms |       22 | avg:   11.414 ms | max:  241.611 ms |
 firefox           |  151.992 ms |      123 | avg:    9.543 ms | max:  153.717 ms |
 xfce4-panel       |   24.324 ms |       47 | avg:    8.189 ms | max:  242.352 ms |
 :5090             |    6.932 ms |      111 | avg:    8.131 ms | max:  102.665 ms |
 events/0          |    0.758 ms |       12 | avg:    1.964 ms | max:   21.879 ms |
 Xorg              |  280.558 ms |      340 | avg:    1.864 ms | max:   99.526 ms |
 geany             |   63.391 ms |      295 | avg:    1.099 ms | max:    9.334 ms |
 reiserfs/0        |    0.039 ms |        2 | avg:    0.854 ms | max:    1.487 ms |
 kondemand/0       |    8.251 ms |      245 | avg:    0.691 ms | max:   34.372 ms |
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We are dividing a time in ns by 1e9. This is a nsec to sec
conversion. What we want is msecs. Fix it by dividing by 1e6.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add a field in the thread atom list that keeps track of the
total and max latencies and also the total runtime. This makes
a faster output and also prepares for sorting.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Currently in perf sched, we are measuring the scheduler wakeup
latencies.

Now we also want measure the time a task wait to be scheduled
after it gets preempted.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To measures the latencies, we capture the sched atoms data into
a specific structure named struct lat_snapshot.

As this structure can be used for other purposes of scheduler
profiling and mirrors what happens in a thread work atom, lets
rename it to struct work_atom and propagate this renaming in
other functions and structures names to keep it coherent.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

After:

-----------------------------------------------------------------------------------
 Task              |  Runtime ms | Switches | Average delay ms | Maximum delay ms |
-----------------------------------------------------------------------------------
 make              |    0.678 ms |       13 | avg:    0.018 ms | max:    0.050 ms |
 gcc               |    0.014 ms |        2 | avg:    0.320 ms | max:    0.627 ms |
 gcc               |    0.000 ms |        2 | avg:    0.185 ms | max:    0.369 ms |
...
-----------------------------------------------------------------------------------
 TOTAL:            |   21.316 ms |       63 |
---------------------------------------------

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: NIngo Molnar <mingo@elte.hu>

Extend the latency tracking structure with scheduling atom
runtime info - and sum it up during per task display.

(Also clean up a few details.)

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: NIngo Molnar <mingo@elte.hu>

After:

-----------------------------------------------------------------------------------
 Task              |  runtime ms | switches | average delay ms | maximum delay ms |
-----------------------------------------------------------------------------------
 migration/0       |    0.000 ms |        1 | avg:    0.047 ms | max:    0.047 ms |
 ksoftirqd/0       |    0.000 ms |        1 | avg:    0.039 ms | max:    0.039 ms |
 migration/1       |    0.000 ms |        3 | avg:    0.013 ms | max:    0.016 ms |
 migration/3       |    0.000 ms |        2 | avg:    0.003 ms | max:    0.004 ms |
 migration/4       |    0.000 ms |        1 | avg:    0.022 ms | max:    0.022 ms |
 distccd           |    0.000 ms |        1 | avg:    0.004 ms | max:    0.004 ms |
 distccd           |    0.000 ms |        1 | avg:    0.014 ms | max:    0.014 ms |
 distccd           |    0.000 ms |        2 | avg:    0.000 ms | max:    0.000 ms |
 distccd           |    0.000 ms |        2 | avg:    0.012 ms | max:    0.019 ms |
 distccd           |    0.000 ms |        1 | avg:    0.002 ms | max:    0.002 ms |
 as                |    0.000 ms |        2 | avg:    0.019 ms | max:    0.019 ms |
 as                |    0.000 ms |        3 | avg:    0.015 ms | max:    0.017 ms |
 as                |    0.000 ms |        1 | avg:    0.009 ms | max:    0.009 ms |
 perf              |    0.000 ms |        1 | avg:    0.001 ms | max:    0.001 ms |
 gcc               |    0.000 ms |        1 | avg:    0.021 ms | max:    0.021 ms |
 run-mozilla.sh    |    0.000 ms |        2 | avg:    0.010 ms | max:    0.017 ms |
 mozilla-plugin-   |    0.000 ms |        1 | avg:    0.006 ms | max:    0.006 ms |
 gcc               |    0.000 ms |        2 | avg:    0.013 ms | max:    0.013 ms |
-----------------------------------------------------------------------------------

(The runtime ms column is not filled in yet.)

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: NIngo Molnar <mingo@elte.hu>

- Separate the latency and the replay commands more cleanly

 - Use consistent naming

 - Display help page on 'perf sched' outlining comments,
   instead of aborting

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: NIngo Molnar <mingo@elte.hu>

Add the -l --latency option that reports statistics about the
scheduler latencies.

For now, the latencies are measured in the following sequence
scope:

- task A is sleeping (D or S state)
- task B wakes up A
         ^
         |
         |

   latency timeframe

         |
         |
         v
- task A is scheduled in

Start by recording every scheduler events:

	perf record -e sched:*

and then fetch the results:

	perf sched -l

 Tasks                     count          total              avg            max

migration/0                  2             39849            19924           28826
ksoftirqd/0                  7            756383           108054          373014
migration/1                  5             45391             9078           10452
ksoftirqd/1                  2            399055           199527          359130
events/0                     8           4780110           597513         4500250
events/1                     9           6353057           705895         2986012
kblockd/0                   42          37805097           900121         5077684

The snapshot are in nanoseconds.

- Count: number of snapshots taken for the given task
- Total: total latencies in nanosec
- Avg  : average of latency between wake up and sched in
- Max  : max snapshot latency
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Create a sched event structure of handlers in which various
sched events reader can plug their own callbacks.

This makes easier the addition of new perf sched sub commands.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

perf sched raises the following error when it meets a sched
switch event:

perf: builtin-sched.c:286: register_pid: Assertion `!(pid >= 65536)' failed.
Abandon

Currently in x86-64, the sched switch events have a hole in the
middle of the structure:

	u16 common_type;
	u8 common_flags;
	u8 common_preempt_count;
	u32 common_pid;
	u32 common_tgid;

	char prev_comm[16];
	u32 prev_pid;
	u32 prev_prio;
			<--- there
	u64 prev_state;
	char next_comm[16];
	u32 next_pid;
	u32 next_prio;

Gcc inserts a 4 bytes hole there for prev_state to be u64
aligned. And the events are exported to userspace with this
hole.

But in userspace, from perf sched, we fetch it using a
structure that has a new field in the beginning: u32 size. This
is because our trace is exported with its size as a field. But
now that we have this new field, the hole in the middle
disappears because it makes prev_state becoming well aligned.

And since we are using a pointer to the raw trace using this
struct, instead of reading prev_state, we are reading the hole.

We could fix it by keeping the size seperate from the struct
but actually there a lot of other potential problems: some
fields may be saved as long in a 64 bits system and later read
as long in a 32 bits system. Also this direct cast doesn't care
about the endianness differences between the host traced
machine and the machine in which we do the post processing.

So instead of using such dangerous direct casts, fetch the
values using the trace parsing API that already takes care of
all these problems.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Currently, when one wants to activate every tracepoint
counters of a subsystem from perf record, the current sequence
is needed:

  perf record -e subsys:ev1 -e subsys:ev2 -e subsys:ev3

This may annoy the most patient of us.

Now we can just do:

  perf record -e subsys:*
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>