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Author SHA1 Message Date
Sean Christopherson
75d7ba32f9 perf tools: Use dedicated non-atomic clear/set bit helpers
Use the dedicated non-atomic helpers for {clear,set}_bit() and their
test variants, i.e. the double-underscore versions.  Depsite being
defined in atomic.h, and despite the kernel versions being atomic in the
kernel, tools' {clear,set}_bit() helpers aren't actually atomic.  Move
to the double-underscore versions so that the versions that are expected
to be atomic (for kernel developers) can be made atomic without affecting
users that don't want atomic operations.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Message-Id: <20221119013450.2643007-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-02 13:22:33 -05:00
Athira Rajeev
72cd652b73 perf affinity: Fix out of bound access to "sched_cpus" mask
The affinity code in "affinity_set" function access array named
"sched_cpus". The size for this array is allocated in affinity_setup
function which is nothing but value from get_cpu_set_size. This is used
to contain the cpumask value for each cpu.

While setting bit for each cpu, it calls "set_bit" function which access
index in sched_cpus array.  If we provide a command-line option to -C
which is more than the number of CPU's present in the system, the
set_bit could access an array member which is out-of the array size.
This is because currently, there is no boundary check for the CPU.  This
will result in seg fault:

<<>>
   ./perf stat -C 12323431 ls
  Perf can support 2048 CPUs. Consider raising MAX_NR_CPUS
  Segmentation fault (core dumped)
<<>>

Fix this by adding boundary check for the array.

After the fix from powerpc system:

<<>>
  ./perf stat -C 12323431 ls 1>out
  Perf can support 2048 CPUs. Consider raising MAX_NR_CPUS

   Performance counter stats for 'CPU(s) 12323431':

     <not supported> msec cpu-clock
     <not supported>      context-switches
     <not supported>      cpu-migrations
     <not supported>      page-faults
     <not supported>      cycles
     <not supported>      instructions
     <not supported>      branches
     <not supported>      branch-misses

         0.001192373 seconds time elapsed
<<>>

Reported-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Signed-off-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20220905141929.7171-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-09-06 09:45:23 -03:00
Arnaldo Carvalho de Melo
1855b796f2 perf affinity: Allow passing a NULL arg to affinity__cleanup()
Just like with free(), NULL is checked to avoid having all callers do
it.

Its convenient for when not using affinity setup/cleanup for dummy CPU
maps, i.e. CPU maps for pid targets.

Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220117160931.1191712-2-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-18 09:24:58 -03:00
Ian Rogers
6d18804b96 perf cpumap: Give CPUs their own type
A common problem is confusing CPU map indices with the CPU, by wrapping
the CPU with a struct then this is avoided. This approach is similar to
atomic_t.

Committer notes:

To make it build with BUILD_BPF_SKEL=1 these files needed the
conversions to 'struct perf_cpu' usage:

  tools/perf/util/bpf_counter.c
  tools/perf/util/bpf_counter_cgroup.c
  tools/perf/util/bpf_ftrace.c

Also perf_env__get_cpu() was removed back in "perf cpumap: Switch
cpu_map__build_map to cpu function".

Additionally these needed to be fixed for the ARM builds to complete:

  tools/perf/arch/arm/util/cs-etm.c
  tools/perf/arch/arm64/util/pmu.c

Suggested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.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: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-49-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:23 -03:00
Andy Shevchenko
7fc5b57132 tools: rename bitmap_alloc() to bitmap_zalloc()
Rename bitmap_alloc() to bitmap_zalloc() in tools to follow the bitmap API
in the kernel.

No functional changes intended.

Link: https://lkml.kernel.org/r/20210814211713.180533-14-yury.norov@gmail.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Suggested-by: Yury Norov <yury.norov@gmail.com>
Acked-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Lobakin <alobakin@pm.me>
Cc: Alexey Klimov <aklimov@redhat.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08 11:50:27 -07:00
Andi Kleen
267ed5d859 perf affinity: Add infrastructure to save/restore affinity
The kernel perf subsystem has to IPI to the target CPU for many
operations. On systems with many CPUs and when managing many events the
overhead can be dominated by lots of IPIs.

An alternative is to set up CPU affinity in the perf tool, then set up
all the events for that CPU, and then move on to the next CPU.

Add some affinity management infrastructure to enable such a model.
Used in followon patches.

Committer notes:

Use zfree() in some places, add missing stdbool.h header, some minor
coding style changes.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-3-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-28 08:08:38 -03:00