Commit 90035d3c authored by Ben Gainey's avatar Ben Gainey Committed by Namhyung Kim
Browse files

tools/perf: Allow inherit + PERF_SAMPLE_READ when opening events 



The "perf record" tool will now default to this new mode if the user
specifies a sampling group when not in system-wide mode, and when
"--no-inherit" is not specified.

This change updates evsel to allow the combination of inherit
and PERF_SAMPLE_READ.

A fallback is implemented for kernel versions where this feature is not
supported.

Signed-off-by: default avatarBen Gainey <ben.gainey@arm.com>
Cc: james.clark@arm.com
Link: https://lore.kernel.org/r/20241001121505.1009685-3-ben.gainey@arm.com


Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
parent 80c281fc

tools/perf/tests/attr/README

+2 −0
Original line number Diff line number Diff line
@@ -51,6 +51,8 @@ Following tests are defined (with perf commands): 
  perf record --call-graph fp kill              (test-record-graph-fp-aarch64)

  perf record -e '{cycles,instructions}' kill   (test-record-group1)

  perf record -e '{cycles/period=1/,instructions/period=2/}:S' kill (test-record-group2)

  perf record -e '{cycles,cache-misses}:S' kill (test-record-group-sampling1)

  perf record -c 10000 -e '{cycles,cache-misses}:S' kill (test-record-group-sampling2)

  perf record -D kill                           (test-record-no-delay)

  perf record -i kill                           (test-record-no-inherit)

  perf record -n kill                           (test-record-no-samples)

tools/perf/tests/attr/test-record-C0

+2 −0
Original line number Diff line number Diff line
@@ -18,5 +18,7 @@ sample_type=65927 
mmap=0

comm=0

task=0

inherit=0



[event:system-wide-dummy]

inherit=0

tools/perf/tests/attr/test-record-dummy-C0

+1 −1
Original line number Diff line number Diff line
@@ -19,7 +19,7 @@ sample_period=4000 
sample_type=391

read_format=4|20

disabled=0

inherit=1

inherit=0

pinned=0

exclusive=0

exclude_user=0

tools/perf/tests/attr/test-record-group-sampling

+2 −1
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
command = record

args    = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1

ret     = 1

kernel_until = 6.12



[event-1:base-record]

fd=1
@@ -18,7 +19,7 @@ group_fd=1 
type=0

config=3



# default | PERF_SAMPLE_READ

# default | PERF_SAMPLE_READ | PERF_SAMPLE_PERIOD

sample_type=343



# PERF_FORMAT_ID | PERF_FORMAT_GROUP  | PERF_FORMAT_LOST

tools/perf/tests/attr/test-record-group-sampling1

0 → 100644
+50 −0
Original line number Diff line number Diff line 
[config]

command = record

args    = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1

ret     = 1

kernel_since = 6.12



[event-1:base-record]

fd=1

group_fd=-1



# cycles

type=0

config=0



# default | PERF_SAMPLE_READ | PERF_SAMPLE_PERIOD

sample_type=343



# PERF_FORMAT_ID | PERF_FORMAT_GROUP  | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING

read_format=28|31

task=1

mmap=1

comm=1

enable_on_exec=1

disabled=1



# inherit is enabled for group sampling

inherit=1



[event-2:base-record]

fd=2

group_fd=1



# cache-misses

type=0

config=3



# default | PERF_SAMPLE_READ | PERF_SAMPLE_PERIOD

sample_type=343



# PERF_FORMAT_ID | PERF_FORMAT_GROUP  | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING

read_format=28|31

task=0

mmap=0

comm=0

enable_on_exec=0

disabled=0

freq=0



# inherit is enabled for group sampling

inherit=1