Like all locally-built programs, dlfilters may need to be re-built if
shared libraries they use change. Also there may be unexpected results
if the dfilter uses different versions of the shared libraries that perf
uses.
Note those things in the documentation.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https //lore.kernel.org/r/20210811101036.17986-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The option --list-dlfilters does use a string value.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 638e2b9984 ("perf script Add option to list dlfilters")
Link: https //lore.kernel.org/r/20210811101036.17986-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
machine_resolve() may have already been called. Test for that to avoid
calling it again unnecessarily.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https //lore.kernel.org/r/20210811101036.17986-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf_dlfilter_fns must not be const, because it is not.
Declaring it const can result in it being mapped read-only, causing a
segfaullt when it is written. Update documentation accordingly.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 8defa7147d5572 ("perf script Add API for filtering via dynamically loaded shared object")
Link: https //lore.kernel.org/r/20210811101036.17986-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Update JSON metrics for SkyLake Server.
Based on TMA metrics 4.21 at 01.org.
https://download.01.org/perfmon/
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https //lore.kernel.org/r/20210810020508.31261-7-yao.jin@linux.intel.com
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Update JSON uncore events for SkyLake Server.
Based on JSON list v1.24:
https://download.01.org/perfmon/SKX/
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https //lore.kernel.org/r/20210810020508.31261-6-yao.jin@linux.intel.com
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Update JSON core events for SkyLake Server.
Based on JSON list v1.24:
https://download.01.org/perfmon/SKX/
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https //lore.kernel.org/r/20210810020508.31261-5-yao.jin@linux.intel.com
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Update JSON metrics for CascadeLake Server.
Based on TMA metrics 4.21 at 01.org.
https://download.01.org/perfmon/
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https //lore.kernel.org/r/20210810020508.31261-4-yao.jin@linux.intel.com
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Update JSON uncore events for CascadeLake Server.
Based on JSON list v1.11:
https://download.01.org/perfmon/CLX/
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https //lore.kernel.org/r/20210810020508.31261-3-yao.jin@linux.intel.com
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Update JSON core events for CascadeLake Server.
Based on JSON list v1.11:
https://download.01.org/perfmon/CLX/
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https //lore.kernel.org/r/20210810020508.31261-2-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support for system events, along with core and uncore events.
Support for a sample PMU is also added.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-12-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Print the SoC name per system event table, which will allow the test SoC be
identified by the pmu-events test.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-11-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Function pmu_add_sys_aliases() will be required for the PMU events test
for system events aliases, so make it public.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-10-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add more events to cover the scenarios fixed and also inadvertently
broken by commit c47a5599ed ("perf tools: Fix pattern matching for
same substring in different PMU type")
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-9-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support to match aliases for uncore PMUs.
Since we cannot rely on the PMUs being present on the host system, use
fake PMUs.
The following conditions in the test are ensures:
- Expected count of aliases created
- All aliases can be matched to an expected alias in
perf_pmu_test_pmu.aliases
This will catch the condition fixed in commit c47a5599ed ("perf tools:
Fix pattern matching for same substring in different PMU type"), where
excess events were created for a PMU. It will also fix the scenario
inadvertently broken there, where no aliases were created for aliases
with multiple tokens.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-8-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Calling pmu_is_uncore() for fake PMUs does not work, as it checks sysfs
for the PMU details (which won't exist).
Check .is_uncore field instead, which makes sense anyway.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-7-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The current method to test uncore event aliasing is limited, as it
relies on the uncore PMU being present in the host system to test.
As such, breakages of uncore PMU aliases goes unnoticed. To make this
more robust, a new method of testing uncore PMUs with fake PMUs will be
used in future. This will be separate to testing core PMU aliases.
So make the current test function core PMU only. Uncore PMU alias
support will be re-added later.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-6-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Factor out alias test which will be used in multiple places.
Also test missing fields.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-5-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently all test events are put into arrays of test events.
Create pointer arrays of test events instead, so the test events may be
referenced later for tighter alias verification.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-4-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In future to add support for sys events, relocate the core and uncore
events to a cpu folder.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-3-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Factor out event comparison which will be used in multiple places.
Also test "pmu" and "compat" fields.
Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-2-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently all JSONs and the mapfile for an arch are dependencies for
building pmu-events.c
The test JSONs are missing as a dependency, so add them.
Signed-off-by: John Garry <john.garry@huawei.com>
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: http://lore.kernel.org/lkml/90094733-741c-50e5-ac7d-f5640b5f0bdd@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This new benchmark finds the total time that is taken to open, mmap,
enable, disable, munmap, close an evlist (time taken for new,
create_maps, config, delete is not counted in).
The evlist can be configured as in perf-record using the
-a,-C,-e,-u,--per-thread,-t,-p options.
The events can be duplicated in the evlist to quickly test performance
with many events using the -n options.
Furthermore, also the number of iterations used to calculate the
statistics is customizable.
Examples:
- Open one dummy event system-wide:
$ sudo ./perf bench internals evlist-open-close
Number of cpus: 4
Number of threads: 1
Number of events: 1 (4 fds)
Number of iterations: 100
Average open-close took: 613.870 usec (+- 32.852 usec)
- Open the group '{cs,cycles}' on CPU 0
$ sudo ./perf bench internals evlist-open-close -e '{cs,cycles}' -C 0
Number of cpus: 1
Number of threads: 1
Number of events: 2 (2 fds)
Number of iterations: 100
Average open-close took: 8503.220 usec (+- 252.652 usec)
- Open 10 'cycles' events for user 0, calculate average over 100 runs
$ sudo ./perf bench internals evlist-open-close -e cycles -n 10 -u 0 -i 100
Number of cpus: 4
Number of threads: 328
Number of events: 10 (13120 fds)
Number of iterations: 100
Average open-close took: 180043.140 usec (+- 2295.889 usec)
Committer notes:
Replaced a deprecated bzero() call with designated initialized zeroing.
Added some missing evlist allocation checks, one noted by Riccardo on
the mailing list.
Minor cosmetic changes (sent in private).
Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210809201101.277594-1-rickyman7@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
" -- " is an em dash (—) in asciidoc, so all these examples that were
supposed to be producing a literal two dashes were being misrendered.
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210809153226.332545-1-hi@alyssa.is
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's useful to know that the kernel is running in 32-bit or 64-bit mode.
E.g. We can decide if perf tool is running in compat mode based on the
info.
This patch adds an item "kernel_is_64_bit" into session's environment
structure perf_env, its value is initialized based on the architecture
string.
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: russell king <linux@armlinux.org.uk>
Link: http://lore.kernel.org/lkml/20210809112727.596876-2-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since the __sync functions have been removed from perf, it's needless
for perf tool to test the feature sync-compare-and-swap.
The feature test is not used by any other components, remove it.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Díaz <daniel.diaz@linaro.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: coresight@lists.linaro.org
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20210809111407.596077-10-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since the __sync functions have been dropped, This patch removes unused
build and checking for HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT in perf tool.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Díaz <daniel.diaz@linaro.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: coresight@lists.linaro.org
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20210809111407.596077-9-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since the function auxtrace_mmap__read_snapshot_head() is exactly same
with auxtrace_mmap__read_head(), whether the session is in snapshot mode
or not, it's unified to use function auxtrace_mmap__read_head() for
reading AUX buffer head.
And the function auxtrace_mmap__read_snapshot_head() is unused so this
patch removes it.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Díaz <daniel.diaz@linaro.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: coresight@lists.linaro.org
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20210809111407.596077-8-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The main purpose for using __sync built-in functions is to support
compat mode for 32-bit perf with 64-bit kernel. But using these
built-in functions might cause potential issues.
__sync functions originally support Intel Itanium processoer [1] but it
cannot promise to support all 32-bit archs. Now these functions have
become the legacy functions.
Considering __sync functions cannot really fix the 64-bit value
atomicity on 32-bit archs, thus this patch drops __sync functions.
Credits to Peter for detailed analysis.
[1] https://gcc.gnu.org/onlinedocs/gcc/_005f_005fsync-Builtins.html#g_t_005f_005fsync-Builtins
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Díaz <daniel.diaz@linaro.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: coresight@lists.linaro.org
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20210809111407.596077-7-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use WRITE_ONCE() for updating aux_tail, so can avoid unexpected memory
behaviour.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Díaz <daniel.diaz@linaro.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: coresight@lists.linaro.org
Cc: x86@kernel.org
Link: http //lore.kernel.org/lkml/20210809111407.596077-6-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The text ranging from "subsystem__event_name" to "raw_syscalls__sys_enter()"
is interpreted by asciidoc as a pair of unconstrained text formatting markers.
The result is that the manual page displayed this text as underlined,
and the HTML pages displayed this text as italicized. Escape the first
double-underscore to prevent this.
https://docs.asciidoctor.org/asciidoc/latest/syntax-quick-reference/
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210806204502.110305-1-stephen.s.brennan@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently decode will silently fail if no binary data is available for
the decode. This is made worse if only partial data is available because
the decode will appear to work, but any trace from that missing DSO will
silently not be generated.
Add a UI popup once if there is any data missing, and then warn in the
bottom left for each individual DSO that's missing.
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http //lore.kernel.org/lkml/20210805130354.878120-2-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add JSON metrics for Icelake Server to perf.
Based on TMA metrics 4.21 at 01.org.
https://download.01.org/perfmon/
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210806075404.31209-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This extends the program to measure WAIT_REQUEUE_PI+CMP_REQUEUE_PI
pairs, which are the underlying machinery behind priority-inheritance
aware condition variables. The defaults are the same as with the regular
non-pi version, requeueing one task at a time, with the exception that
PI will always wakeup the first waiter.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20210809043301.66002-8-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Do not assume success and account for EAGAIN or any other return value,
however unlikely.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20210809043301.66002-7-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Such that all threads are requeued to uaddr2 in a single
futex_cmp_requeue(), unlike the default, which is 1.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20210809043301.66002-6-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This adds, across all futex benchmarks, the -m/--mlockall option
which is a common operation for realtime workloads by not incurring
in page faults in paths that want determinism. As such, threads
started after a call to mlockall(2) will generate page faults
immediately since the new stack is immediately forced to memory,
due to the MCL_FUTURE flag.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20210809043301.66002-5-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Do this across all futex-bench tests such that all program parameters
neatly share a common structure, which is nicer than how we have them
now. No changes in program behavior are expected.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20210809043301.66002-2-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Only show the warning if the user hasn't already set timeless mode and
improve the text because there was ambiguity around the meaning of '...'
Change the warning to a UI warning instead of printing straight to
stderr because this corrupts the UI when perf report TUI is used. The UI
warning function also handles printing to stderr when in perf script
mode.
Suggested-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20210729155805.2830-6-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Auxtrace support may need DSOs for decoding (for example Arm Coresight).
If one of these is missing it would make sense to warn once for each one
that's missing, but not flood the output with every address as there
could be thousands of lookups.
This flag will allow tracking whether a warning was shown for each DSO.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20210729155805.2830-5-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently 'perf annotate --stdio' (and --stdio2) will exit without
printing anything if there are disassembly errors. Apply the same error
handler that's used for TUI and GTK modes. This makes comparing
disassembly across the different modes more consistent.
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20210729155805.2830-4-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Setting annotate_warned to true on errors was removed in
commit ee51d85139 ("perf annotate: Introduce strerror for handling
symbol__disassemble() errors") which means when 'perf annotate
--skip-missing' is used warnings are shown multiple times for the same
DSO.
Setting this again restores the original behavior of only one warning
each.
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20210729155805.2830-3-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently WARN_ONCE prints to stderr and corrupts the TUI. Add
equivalent methods for UI warnings.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20210729155805.2830-2-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It builds a test program and use it to verify pipe behavior with perf
record, inject and report.
$ perf test pipe -v
80: perf pipe recording and injection test :
--- start ---
test child forked, pid 1109301
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
1109315 1109315 -1 |test.file.MGNff
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
99.99% test.file.MGNff test.file.MGNffM [.] noploop
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
99.99% test.file.MGNff test.file.MGNffM [.] noploop
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.153 MB /tmp/perf.data.dmsnlx (3995 samples) ]
99.99% test.file.MGNff test.file.MGNffM [.] noploop
test child finished with 0
---- end ----
perf pipe recording and injection test: Ok
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210719223153.1618812-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the input is a regular file but the output is a pipe, it should
write a pipe header. But just repiping would write a portion of the
existing header which is different in 'size' value. So we need to
prevent it and write a new pipe header along with other information
like event attributes and features.
This can handle something like this:
# perf record -a -B sleep 1
# perf inject -b -i perf.data | perf report -i -
Factor out perf_event__synthesize_for_pipe() to be shared between perf
record and inject.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210719223153.1618812-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Sometimes it needs to save the perf inject data to a file for debugging.
But normally it assumes the same format for input and output, so the end
result cannot be used due to a broken format.
# perf record -a -o - sleep 1 | perf inject -b -o my.data
# perf report -i my.data --stdio
0x208 [0]: failed to process type: 0 [Invalid argument]
Error:
failed to process sample
# To display the perf.data header info, please use --header/--header-only options.
#
In this case, it thought the data has a regular file header since the
output is not a pipe. But actually it doesn't have one and has a pipe
file header. At the end of the session, it tries to rewrite the regular
file header with updated features and it overwrites the data just
follows the pipe header.
Fix it by checking either the input and the output is a pipe.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210719223153.1618812-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently it unconditionally writes to stdout for repipe. But perf
inject can direct its output to a regular file. Then it needs to
write the header to the file as well.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210719223153.1618812-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The repipe argument is only used by perf inject and the all others
passes 'false'. Let's remove it from the function signature and add
__perf_session__new() to be called from perf inject directly.
This is a preparation of the change the pipe input/output.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210719223153.1618812-2-namhyung@kernel.org
[ Fixed up some trivial conflicts as this patchset fell thru the cracks ;-( ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
https://github.com/beaker-project/restraint/issues/215 describes a file
descriptor leak which revealed the test failure described here.
The 'DSO data reopen' perf test assumes that RLIMIT_NOFILE limits the
number of open file descriptors, but it actually limits newly opened
file descriptors. When the file descriptor limit is reduced, file
descriptors already open remain open regardless of the new limit. This
test failure does not occur if open file descriptors are contiguous,
beginning at zero.
The following command triggers this perf test failure.
perf test 'DSO data reopen' 3>/dev/null 8>/dev/null
This patch determines the file descriptor limit by opening four files
and then closing them. The limit is set to the fourth file descriptor,
leaving only the first three available because any newly opened file
descriptor must be less than the limit.
Signed-off-by: Eirik Fuller <efuller@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Michael Petlan <mpetlan@redhat.com>
LPU-Reference: 20210626023825.1398547-1-efuller@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
