PMU alias names were computed when the first perf_pmu is created,
scanning all PMUs in event sources for a file called alias that
generally doesn't exist. Switch to trying to load the file when all
PMU related files are loaded in lookup. This would cause a PMU name
lookup of an alias name to fail if no PMUs were loaded, so in that
case all PMUs are loaded and the find repeated. The overhead is
similar but in the (very) general case not all PMUs are scanned for
the alias file.
As the overhead occurs once per invocation it doesn't show in perf
bench internals pmu-scan. On a tigerlake machine, the number of openat
system calls for an event of cpu/cycles/ with perf stat reduces from
94 to 69 (ie 25 fewer openat calls).
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: James Clark <james.clark@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20230925062323.840799-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Testcase "Parsing of all PMU events from sysfs" parse events for
all PMUs, and not just cpu. In case of powerpc, the PowerVM
environment supports events from hv_24x7 and hv_gpci PMU which
is of example format like below:
- hv_24x7/CPM_ADJUNCT_INST,domain=?,core=?/
- hv_gpci/event,partition_id=?/
The value for "?" needs to be filled in depending on system
configuration. It is better to skip these parametrized events
in this test as it is done in:
'commit b50d691e50 ("perf test: Fix "all PMU test" to skip
parametrized events")' which handled a simialr instance with
"all PMU test".
Fix parse-events test to skip parametrized events since
it needs proper setup of the parameters.
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Ian Rogers <irogers@google.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Cc: maddy@linux.ibm.com
Cc: disgoel@linux.vnet.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20230927181703.80936-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The BTF func proto for a tracepoint has one more argument than the
actual tracepoint function since it has a context argument at the
begining. So it should compare to 5 when the tracepoint has 4
arguments.
typedef void (*btf_trace_sched_switch)(void *, bool, struct task_struct *, struct task_struct *, unsigned int);
Also, recent change in the perf tool would use a hand-written minimal
vmlinux.h to generate BTF in the skeleton. So it won't have the info
of the tracepoint. Anyway it should use the kernel's vmlinux BTF to
check the type in the kernel.
Fixes: b36888f71c ("perf record: Handle argument change in sched_switch")
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Song Liu <song@kernel.org>
Cc: Hao Luo <haoluo@google.com>
CC: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230922234444.3115821-1-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
To save pid of child processes when creating worker:
1. The messaging worker is changed to `union` type to store thread id and
process pid.
2. Save child process pid in create_process_worker().
3. Rename `pth_tab` as `work_tab`.
Test result:
# perf bench sched messaging
# Running 'sched/messaging' benchmark:
# 20 sender and receiver processes per group
# 10 groups == 400 processes run
Total time: 6.744 [sec]
# perf bench sched messaging -t
# Running 'sched/messaging' benchmark:
# 20 sender and receiver threads per group
# 10 groups == 400 threads run
Total time: 5.788 [sec]
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20230923093037.961232-4-yangjihong1@huawei.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Refactor the create_worker() helper:
1. Modify the return value and use pthread pointer as a parameter to
facilitate value assignment in create_worker().
2. The thread worker creation and process worker creation are abstracted
into independent helpers.
No functional change.
Test result:
# perf bench sched messaging
# Running 'sched/messaging' benchmark:
# 20 sender and receiver processes per group
# 10 groups == 400 processes run
Total time: 6.332 [sec]
# perf bench sched messaging -t
# Running 'sched/messaging' benchmark:
# 20 sender and receiver threads per group
# 10 groups == 400 threads run
Total time: 5.545 [sec]
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20230923093037.961232-3-yangjihong1@huawei.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Running shellcheck on stat+shadow_stat.sh generates below
warning
In tests/shell/stat+csv_summary.sh line 26:
while read _num _event _run _pct
^--^ SC2034: _num appears unused. Verify use (or export if used externally).
^----^ SC2034: _event appears unused. Verify use (or export if used externally).
^--^ SC2034: _run appears unused. Verify use (or export if used externally).
^--^ SC2034: _pct appears unused. Verify use (or export if used externally).
This variable is intentionally unused since it is
needed to parse through the output. commit used "_"
as a prefix for this throw away variable. But this
stil shows warning with shellcheck v0.6. Fix this
by only using "_" instead of prefix and variable name.
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Cc: maddy@linux.ibm.com
Cc: disgoel@linux.vnet.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20230907171540.36736-3-atrajeev@linux.vnet.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Dummy events are created with an attribute where the period and freq
are zero. evsel__config will then see the uninitialized values and
initialize them in evsel__default_freq_period. As fequency mode is
used by default the dummy event would be set to use frequency
mode. However, this has no effect on the dummy event but does cause
unnecessary timers/interrupts. Avoid this overhead by setting the
period to 1 for dummy events.
evlist__add_aux_dummy calls evlist__add_dummy then sets freq=0 and
period=1. This isn't necessary after this change and so the setting is
removed.
From Stephane:
The dummy event is not counting anything. It is used to collect mmap
records and avoid a race condition during the synthesize mmap phase of
perf record. As such, it should not cause any overhead during active
profiling. Yet, it did. Because of a bug the dummy event was
programmed as a sampling event in frequency mode. Events in that mode
incur more kernel overheads because on timer tick, the kernel has to
look at the number of samples for each event and potentially adjust
the sampling period to achieve the desired frequency. The dummy event
was therefore adding a frequency event to task and ctx contexts we may
otherwise not have any, e.g.,
perf record -a -e cpu/event=0x3c,period=10000000/.
On each timer tick the perf_adjust_freq_unthr_context() is invoked and
if ctx->nr_freq is non-zero, then the kernel will loop over ALL the
events of the context looking for frequency mode ones. In doing, so it
locks the context, and enable/disable the PMU of each hw event. If all
the events of the context are in period mode, the kernel will have to
traverse the list for nothing incurring overhead. The overhead is
multiplied by a very large factor when this happens in a guest kernel.
There is no need for the dummy event to be in frequency mode, it does
not count anything and therefore should not cause extra overhead for
no reason.
Fixes: 5bae025023 ("perf evlist: Introduce perf_evlist__new_dummy constructor")
Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20230916035640.1074422-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The test was failing in specific scenarios due to imperfection of FP
arithmetics. The `bc` command wasn't correctly rounding the result of
division causing the failure.
Replace the `bc` with `awk` which should work with more decimal places
and add a threshold to catch any possible rounding errors. The
acceptable rounding error is set to 0.01 when the test passes with a
warning message.
Signed-off-by: Veronika Molnarova <vmolnaro@redhat.com>
Acked-by: Michael Petlan <mpetlan@redhat.com>
Link: https://lore.kernel.org/r/20230919150419.23193-1-vmolnaro@redhat.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The struct "pmu_events_table" has been changed after commit
2e255b4f9f (perf jevents: Group events by PMU, 2023-08-23).
So there doesn't exist 'entries' in pmu_events_table anymore.
This will align the members with that commit. Othewise, below
errors will be printed when run jevent.py:
pmu-events/pmu-events.c:5485:26: error: ‘struct pmu_metrics_table’ has no member named ‘entries’
5485 | .entries = pmu_metrics__freescale_imx8dxl_sys,
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Tested-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20230919080929.3807123-1-xu.yang_2@nxp.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Fuzzing found that an invalid tracepoint name would create a memory
leak with an address sanitizer build:
```
$ perf stat -e '*:o/' true
event syntax error: '*:o/'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
=================================================================
==59380==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 4 byte(s) in 2 object(s) allocated from:
#0 0x7f38ac07077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439
#1 0x55f2f41be73b in str util/parse-events.l:49
#2 0x55f2f41d08e8 in parse_events_lex util/parse-events.l:338
#3 0x55f2f41dc3b1 in parse_events_parse util/parse-events-bison.c:1464
#4 0x55f2f410b8b3 in parse_events__scanner util/parse-events.c:1822
#5 0x55f2f410d1b9 in __parse_events util/parse-events.c:2094
#6 0x55f2f410e57f in parse_events_option util/parse-events.c:2279
#7 0x55f2f4427b56 in get_value tools/lib/subcmd/parse-options.c:251
#8 0x55f2f4428d98 in parse_short_opt tools/lib/subcmd/parse-options.c:351
#9 0x55f2f4429d80 in parse_options_step tools/lib/subcmd/parse-options.c:539
#10 0x55f2f442acb9 in parse_options_subcommand tools/lib/subcmd/parse-options.c:654
#11 0x55f2f3ec99fc in cmd_stat tools/perf/builtin-stat.c:2501
#12 0x55f2f4093289 in run_builtin tools/perf/perf.c:322
#13 0x55f2f40937f5 in handle_internal_command tools/perf/perf.c:375
#14 0x55f2f4093bbd in run_argv tools/perf/perf.c:419
#15 0x55f2f409412b in main tools/perf/perf.c:535
SUMMARY: AddressSanitizer: 4 byte(s) leaked in 2 allocation(s).
```
Fix by adding the missing destructor.
Fixes: 865582c3f4 ("perf tools: Adds the tracepoint name parsing support")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: He Kuang <hekuang@huawei.com>
Link: https://lore.kernel.org/r/20230914164028.363220-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pmu__find_core_pmu() more logically belongs in pmus.c because it
iterates over all PMUs, so move it to pmus.c
At the same time rename it to perf_pmus__find_core_pmu() to match the
naming convention in this file.
list_prepare_entry() can't be used in perf_pmus__scan_core() anymore now
that it's called from the same compilation unit. This is with -O2
(specifically -O1 -ftree-vrp -finline-functions
-finline-small-functions) which allow the bounds of the array
access to be determined at compile time. list_prepare_entry() subtracts
the offset of the 'list' member in struct perf_pmu from &core_pmus,
which isn't a struct perf_pmu. The compiler sees that pmu results in
&core_pmus - 8 and refuses to compile. At runtime this works because
list_for_each_entry_continue() always adds the offset back again before
dereferencing ->next, but it's technically undefined behavior. With
-fsanitize=undefined an additional warning is generated.
Using list_first_entry_or_null() to get the first entry here avoids
doing &core_pmus - 8 but has the same result and fixes both the compile
warning and the undefined behavior warning. There are other uses of
list_prepare_entry() in pmus.c, but the compiler doesn't seem to be
able to see that they can also be called with &core_pmus, so I won't
change any at this time.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Haixin Yu <yuhaixin.yhx@linux.alibaba.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230913153355.138331-2-james.clark@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Makefile.perf uses "CONFIG_*" checks in the code. Example the config for
libtraceevent is used to set PYTHON_EXT_SRCS
ifeq ($(CONFIG_LIBTRACEEVENT),y)
PYTHON_EXT_SRCS := $(shell grep -v ^\# util/python-ext-sources)
else
PYTHON_EXT_SRCS := $(shell grep -v '^\#\|util/trace-event.c' util/python-ext-sources)
endif
But this is not picking the value for CONFIG_LIBTRACEEVENT that is set
using the settings in Makefile.config. Include the file
".config-detected" so that make will use the system detected
configuration in the CONFIG checks.
This will fix isues that could arise when other "CONFIG_*" checks are
added to Makefile.perf in future as well.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20230912063807.74250-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
