linux.git/tools/perf/util/stat.h, branch v4.13

perf stat: Add support to measure SMI cost

2017-06-21T14:35:35+00:00

Implementing a new --smi-cost mode in perf stat to measure SMI cost.

During the measurement, the /sys/device/cpu/freeze_on_smi will be set.

The measurement can be done with one counter (unhalted core cycles), and
two free running MSR counters (IA32_APERF and SMI_COUNT).

In practice, the percentages of SMI core cycles should be more useful
than absolute value. So the output will be the percentage of SMI core
cycles and SMI#. metric_only will be set by default.

SMI cycles% = (aperf - unhalted core cycles) / aperf

Here is an example output.

 Performance counter stats for 'sudo echo ':

SMI cycles%          SMI#
    0.1%              1

       0.010858678 seconds time elapsed

Users who wants to get the actual value can apply additional
--no-metric-only.

Signed-off-by: Kan Liang 
Acked-by: Jiri Olsa 
Cc: Andi Kleen 
Cc: Kan Liang 
Cc: Peter Zijlstra 
Cc: Robert Elliott 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1495825538-5230-3-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Output JSON MetricExpr metric

2017-03-23T14:42:30+00:00

Add generic infrastructure to perf stat to output ratios for
"MetricExpr" entries in the event lists. Many events are more useful as
ratios than in raw form, typically some count in relation to total
ticks.

Transfer the MetricExpr information from the alias to the evsel.

We mark the events that need to be collected for MetricExpr, and also
link the events using them with a pointer. The code is careful to always
prefer the right event in the same group to minimize multiplexing
errors. At the moment only a single relation is supported.

Then add a rblist to the stat shadow code that remembers stats based on
the cpu and context.

Then finally update and retrieve and print these values similarly to the
existing hardcoded perf metrics. We use the simple expression parser
added earlier to evaluate the expression.

Normally we just output the result without further commentary, but for
--metric-only this would lead to empty columns. So for this case use the
original event as description.

There is no attempt to automatically add the MetricExpr event, if it is
missing, however we suggest it to the user, because the user tool
doesn't have enough information to reliably construct a group that is
guaranteed to schedule. So we leave that to the user.

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}'
       1.000147889        800,085,181      unc_p_clockticks
       1.000147889         93,126,241      unc_p_freq_max_os_cycles  #     11.6
       2.000448381        800,218,217      unc_p_clockticks
       2.000448381        142,516,095      unc_p_freq_max_os_cycles  #     17.8
       3.000639852        800,243,057      unc_p_clockticks
       3.000639852        162,292,689      unc_p_freq_max_os_cycles  #     20.3

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
  #    time         freq_max_os_cycles %
       1.000127077      0.9
       2.000301436      0.7
       3.000456379      0.0

v2: Change from DivideBy to MetricExpr
v3: Use expr__ prefix.  Support more than one other event.
v4: Update description
v5: Only print warning message once for multiple PMUs.

Signed-off-by: Andi Kleen 
Acked-by: Jiri Olsa 
Link: http://lkml.kernel.org/r/20170320201711.14142-11-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add computation of TopDown formulas

2016-06-06T20:04:16+00:00

Implement the TopDown formulas in 'perf stat'. The topdown basic metrics
reported by the kernel are collected, and the formulas are computed and
output as normal metrics.

See the kernel commit exporting the events for details on the used
metrics.

Committer note:

Output example:

  # perf stat --topdown -a usleep 1

   Performance counter stats for 'system wide':

             retiring     bad speculation   frontend bound   backend bound
  S0-C0    2     23.8%       11.6%            28.3%           36.3%
  S0-C1    2     16.2%       15.7%            36.5%           31.6%

         0.000579956 seconds time elapsed
  #

v2: Always print all metrics, only use thresholds for coloring.
v3: Mark retiring over threshold green, not red.
v4: Only print one decimal digit
    Fix color printing of one metric
v5: Avoid printing -0.0
v6: Remove extra frontend event lookup

Signed-off-by: Andi Kleen 
Acked-by: Jiri Olsa 
Link: http://lkml.kernel.org/r/1464119559-17203-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Check for frontend stalled for metrics

2016-03-03T14:10:40+00:00

Add an extra check for frontend stalled in the metrics.  This avoids an
extra column for the --metric-only case when the CPU does not support
frontend stalled.

v2: Add separate init function

Signed-off-by: Andi Kleen 
Acked-by: Jiri Olsa 
Link: http://lkml.kernel.org/r/1456858672-21594-8-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Abstract stat metrics printing

2016-02-16T20:13:00+00:00

Abstract the printing of shadow metrics. Instead of every metric calling
fprintf directly and taking care of indentation, use two call backs: one
to print metrics and another to start a new line.

This will allow adding metrics to CSV mode and also using them for other
purposes.

The computation of padding is now done in the central callback, instead
of every metric doing it manually.  This makes it easier to add new
metrics.

v2: Refactor functions, printout now does more. Move
shadow printing. Improve fallback callbacks. Don't
use void * callback data.
v3: Remove unnecessary hunk. Add typedef for new_line
v4: Remove unnecessary hunk. Don't print metrics for CSV/interval
mode yet.  Move printout change to separate patch.
v5: Fix bisect bugs. Avoid bogus frontend cycles printing.
Fix indentation in different aggregation modes.
v6: Delay newline handling

Signed-off-by: Andi Kleen 
Acked-by: Jiri Olsa 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1454173616-17710-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Making several helper functions static

2016-01-26T14:52:43+00:00

There's no need for the following functions to be global:

  perf_evsel__reset_stat_priv
  perf_evsel__alloc_stat_priv
  perf_evsel__free_stat_priv
  perf_evsel__alloc_prev_raw_counts
  perf_evsel__free_prev_raw_counts
  perf_evsel__alloc_stats

They all ended up in util/stat.c, and they no longer need to be called
from outside this object.

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1453290995-18485-5-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add stat events fprintf functions

2015-12-17T18:09:38+00:00

Introducing the following functions to display the stat events for raw
dump.

  perf_event__fprintf_stat
  perf_event__fprintf_stat_round
  perf_event__fprintf_stat_config

Signed-off-by: Jiri Olsa 
Tested-by: Kan Liang 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1445784728-21732-20-git-send-email-jolsa@kernel.org
[ s/stat/st/g and s/round/rd/g parameters to fix 'already defined' build error with older distros (e.g. RHEL6.7) ]
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add stat event read function

2015-12-17T17:55:43+00:00

Introducing the perf_event__process_stat_event function to process a
'struct perf_stat' data from a stat event.

Signed-off-by: Jiri Olsa 
Tested-by: Kan Liang 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1445784728-21732-17-git-send-email-jolsa@kernel.org
[ Renamed 'stat' parameter to 'st' to fix 'already defined' build error with older distros (e.g. RHEL6.7) ]
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add AGGR_UNSET mode

2015-10-19T21:02:07+00:00

Adding AGGR_UNSET mode, so we could distinguish unset aggr_mode in
following patches.

Signed-off-by: Jiri Olsa 
Tested-by: Kan Liang 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1444992092-17897-30-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Rename perf_stat struct into perf_stat_evsel

2015-10-19T21:01:05+00:00

It's used as the perf_evsel::priv data, so the name suits better. Also
we'll need the perf_stat name free for more generic struct.

Signed-off-by: Jiri Olsa 
Tested-by: Kan Liang 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1444992092-17897-29-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo