linux.git/tools/perf/tests/expr.c, branch v5.16-rc2

perf expr: Add source_count for aggregating events

2021-11-13T21:11:50+00:00

Events like uncore_imc/cas_count_read/ on Skylake open multiple events
and then aggregate in the metric leader. To determine the average value
per event the number of these events is needed. Add a source_count
function that returns this value by counting the number of events with
the given metric leader. For most events the value is 1 but for
uncore_imc/cas_count_read/ it can yield values like 6.

Add a generic test, but manually tested with a test metric that uses
the function.

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Ingo Molnar 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Paul A . Clarke 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Song Liu 
Cc: Wan Jiabing 
Cc: Yury Norov 
Link: https://lore.kernel.org/r/20211111002109.194172-9-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf expr: Add metric literals for topology.

2021-11-13T21:11:50+00:00

Allow the number of cpus, cores, dies and packages to be queried by a
metric expression.

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Ingo Molnar 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Paul A . Clarke 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Song Liu 
Cc: Wan Jiabing 
Cc: Yury Norov 
Link: https://lore.kernel.org/r/20211111002109.194172-7-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf test: Add expr test for events with hyphens

2021-11-13T21:11:50+00:00

An example of such an event is topdown-fe-bound.

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Ingo Molnar 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Paul A . Clarke 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Song Liu 
Cc: Wan Jiabing 
Cc: Yury Norov 
Link: https://lore.kernel.org/r/20211111002109.194172-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf test: Rename struct test to test_suite

2021-11-13T13:32:22+00:00

This is to align with kunit's terminology.

Signed-off-by: Ian Rogers 
Tested-by: Sohaib Mohamed 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Brendan Higgins 
Cc: Daniel Latypov 
Cc: David Gow 
Cc: Ingo Molnar 
Cc: Jin Yao 
Cc: John Garry 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Paul Clarke 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20211104064208.3156807-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf test: Move each test suite struct to its test

2021-11-13T13:30:58+00:00

Rather than export test functions, export the test struct. Rename with a
suite__ prefix to avoid name collisions.

Committer notes:

Its '&suite__vectors_page', not '&suite__vectors_pages', noticed when
cross building to arm (32-bit).

Signed-off-by: Ian Rogers 
Tested-by: Sohaib Mohamed 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Brendan Higgins 
Cc: Daniel Latypov 
Cc: David Gow 
Cc: Ingo Molnar 
Cc: Jin Yao 
Cc: John Garry 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Paul Clarke 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20211104064208.3156807-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf metric: Encode and use metric-id as qualifier

2021-10-20T13:57:05+00:00

For a metric like IPC a group of events like {instructions,cycles}:W
would be formed.

If the events names were changed in parsing then the metric expression
parser would fail to find them.

This change makes the event encoding be something like:

  {instructions/metric-id=instructions/, cycles/metric-id=cycles/}

and then uses the evsel's stable metric-id value to locate the events.

This fixes the case that an event is restricted to user because of the
paranoia setting:

  $ echo 2 > /proc/sys/kernel/perf_event_paranoid
  $ perf stat -M IPC /bin/true
   Performance counter stats for '/bin/true':

             150,298      inst_retired.any:u        #      0.77 IPC
             187,095      cpu_clk_unhalted.thread:u

         0.002042731 seconds time elapsed

         0.000000000 seconds user
         0.002377000 seconds sys

Adding the metric-id as a qualifier has a complication in that
qualifiers will become embedded in qualifiers.

For example, msr/tsc/ could become msr/tsc,metric-id=msr/tsc// which
will fail parse-events.

To solve this problem the metric is encoded and decoded for the
metric-id with ! standing in for an encoded value.

Previously ! wasn't parsed.

With this msr/tsc/ becomes msr/tsc,metric-id=msr!3tsc!3/

The metric expression parser is changed so that @ isn't changed to /,
instead this is done when the ID is encoded for parse events.

metricgroup__add_metric_non_group() and metricgroup__add_metric_weak_group()
need to inject the metric-id qualifier, so to avoid repetition they are
merged into a single metricgroup__build_event_string with error codes
more rigorously checked.

stat-shadow's prepare_metric() uses the metric-id to match the metricgroup
code.

As "metric-id=..." is added to all events, it is adding during testing
with the fake PMU.

This complicates pmu_str_check code as PE_PMU_EVENT_FAKE won't match as
part of a configuration.

The testing fake PMU case is fixed so that if a known qualifier with an
! is parsed then it isn't reported as a fake PMU.

This is sufficient to pass all testing but it and the original mechanism
are somewhat brittle.

Signed-off-by: Ian Rogers 
Acked-by: Andi Kleen 
Cc: Adrian Hunter 
Cc: Alexander Antonov 
Cc: Alexander Shishkin 
Cc: Andrew Kilroy 
Cc: Andrew Morton 
Cc: Changbin Du 
Cc: Denys Zagorui 
Cc: Fabian Hemmer 
Cc: Felix Fietkau 
Cc: Heiko Carstens 
Cc: Ingo Molnar 
Cc: Jacob Keller 
Cc: Jiapeng Chong 
Cc: Jin Yao 
Cc: Jiri Olsa 
Cc: Joakim Zhang 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Kees Kook 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nicholas Fraser 
Cc: Nick Desaulniers 
Cc: Paul Clarke 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Sami Tolvanen 
Cc: ShihCheng Tu 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Sumanth Korikkar 
Cc: Thomas Richter 
Cc: Wan Jiabing 
Cc: Zhen Lei 
Link: https://lore.kernel.org/r/20211015172132.1162559-17-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf metric: Modify resolution and recursion check

2021-10-20T13:35:33+00:00

Modify resolution. Rather than resolving a list of metrics, resolve a
metric immediately after it is added.

This simplifies knowing the root of the metric's tree so that IDs may be
associated with it.

A bug in the current implementation is that all the IDs were placed on
the first metric in a metric group.

Rather than maintain data on IDs' parents to detect cycles, maintain
a list of visited metrics and detect cycles if the same metric is
visited twice.

Only place the root metric onto the list of metrics.

Signed-off-by: Ian Rogers 
Acked-by: Andi Kleen 
Cc: Adrian Hunter 
Cc: Alexander Antonov 
Cc: Alexander Shishkin 
Cc: Andrew Kilroy 
Cc: Andrew Morton 
Cc: Changbin Du 
Cc: Denys Zagorui 
Cc: Fabian Hemmer 
Cc: Felix Fietkau 
Cc: Heiko Carstens 
Cc: Ingo Molnar 
Cc: Jacob Keller 
Cc: Jiapeng Chong 
Cc: Jin Yao 
Cc: Jiri Olsa 
Cc: Joakim Zhang 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Kees Kook 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nicholas Fraser 
Cc: Nick Desaulniers 
Cc: Paul Clarke 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Sami Tolvanen 
Cc: ShihCheng Tu 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Sumanth Korikkar 
Cc: Thomas Richter 
Cc: Wan Jiabing 
Cc: Zhen Lei 
Link: https://lore.kernel.org/r/20211015172132.1162559-10-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf metric: Move runtime value to the expr context

2021-10-20T13:33:02+00:00

The runtime value is needed when recursively parsing metrics, currently
a value of 1 is passed which is incorrect.

Rather than add more arguments to the bison parser, add runtime to the
context.

Fix call sites not to pass a value. The runtime value is defaulted to 0,
which is arbitrary. In some places this replaces a value of 1, which was
also arbitrary.

This shouldn't affect anything other than PPC.

The use of 0 or 1 shouldn't matter as a proper runtime value would be
needed in a case that it did matter.

Signed-off-by: Ian Rogers 
Acked-by: Andi Kleen 
Cc: Adrian Hunter 
Cc: Alexander Antonov 
Cc: Alexander Shishkin 
Cc: Andrew Kilroy 
Cc: Andrew Morton 
Cc: Changbin Du 
Cc: Denys Zagorui 
Cc: Fabian Hemmer 
Cc: Felix Fietkau 
Cc: Heiko Carstens 
Cc: Ingo Molnar 
Cc: Jacob Keller 
Cc: Jiapeng Chong 
Cc: Jin Yao 
Cc: Jiri Olsa 
Cc: Joakim Zhang 
Cc: John Garry 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Kees Kook 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Nicholas Fraser 
Cc: Nick Desaulniers 
Cc: Paul Clarke 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Sami Tolvanen 
Cc: ShihCheng Tu 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Sumanth Korikkar 
Cc: Thomas Richter 
Cc: Wan Jiabing 
Cc: Zhen Lei 
Link: https://lore.kernel.org/r/20211015172132.1162559-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf metric: Avoid events for an 'if' constant result

2021-09-29T16:51:04+00:00

For a metric like:

  CONST if expr else CONST

if the values of CONST are identical then expr doesn't need evaluating,
and events, in order to compute a result.

Signed-off-by: Ian Rogers 
Tested-by: John Garry 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Ingo Molnar 
Cc: Jin Yao 
Cc: Kajol Jain 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Paul Clarke 
Cc: Peter Zijlstra 
Cc: Sandeep Dasgupta 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20210923074616.674826-14-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf metric: Don't compute unused events

2021-09-29T16:51:04+00:00

For a metric like:

  EVENT1 if #smt_on else EVENT2

currently EVENT1 and EVENT2 will be measured and then when the metric is
reported EVENT1 or EVENT2 will be printed depending on the value from
smt_on() during the expr parsing. Computing both events is unnecessary and
can lead to multiplexing as discussed in this thread:

  https://lore.kernel.org/lkml/20201110100346.2527031-1-irogers@google.com/

If the input is constant to certain operators like:

 IDS1 if CONST else IDS2

then the result will be either IDS1 or IDS2 depending on CONST (which
may be evaluated from an entire expression), and so IDS1 or IDS2 may
be discarded avoiding events from being programmed.

Signed-off-by: Ian Rogers 
Tested-by: John Garry 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Ingo Molnar 
Cc: Jin Yao 
Cc: Kajol Jain 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Paul Clarke 
Cc: Peter Zijlstra 
Cc: Sandeep Dasgupta 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20210923074616.674826-13-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo