linux.git/tools/perf/util/env.c, branch for-next

perf header: Avoid transitive PMU includes

2024-11-16T19:39:59+00:00

Currently satisfied via header.h. Note, pmu.h includes parse-events.h.

Reviewed-by: James Clark 
Signed-off-by: Ian Rogers 
Tested-by: Xu Yang 
Cc: Adrian Hunter 
Cc: Albert Ou 
Cc: Alexander Shishkin 
Cc: Alexandre Ghiti 
Cc: Athira Rajeev 
Cc: Ben Zong-You Xie 
Cc: Benjamin Gray 
Cc: Bibo Mao 
Cc: Clément Le Goffic 
Cc: Dima Kogan 
Cc: Dr. David Alan Gilbert 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Palmer Dabbelt 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Will Deacon 
Cc: Yicong Yang 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-riscv@lists.infradead.org
Link: https://lore.kernel.org/r/20241107162035.52206-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf header: Refactor get_cpuid to take a CPU for ARM

2024-11-16T19:37:54+00:00

ARM BIG.little has no notion of a constant CPUID for both core
types. To reflect this reality, change the get_cpuid function to also
pass in a possibly unused logical cpu.

If the dummy value (-1) is passed in then ARM can, as currently happens,
select the first logical CPU's "CPUID".

The changes to ARM getcpuid happen in a follow up change.

Reviewed-by: James Clark 
Signed-off-by: Ian Rogers 
Tested-by: Xu Yang 
Cc: Adrian Hunter 
Cc: Albert Ou 
Cc: Alexander Shishkin 
Cc: Alexandre Ghiti 
Cc: Athira Rajeev 
Cc: Ben Zong-You Xie 
Cc: Benjamin Gray 
Cc: Bibo Mao 
Cc: Clément Le Goffic 
Cc: Dima Kogan 
Cc: Dr. David Alan Gilbert 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Palmer Dabbelt 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Will Deacon 
Cc: Yicong Yang 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-riscv@lists.infradead.org
Link: https://lore.kernel.org/r/20241107162035.52206-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Move x86__is_amd_cpu() to util/env.c

2024-10-22T16:55:07+00:00

It can be called from non-x86 platform so let's move it to the general
util directory.  Also add a new helper perf_env__is_x86_amd_cpu() so
that it can be called with an existing perf_env as well.

Reviewed-by: James Clark 
Reviewed-by: Ravi Bangoria 
Acked-by: Kan Liang 
Cc: James Clark 
Cc: Atish Patra 
Cc: Mingwei Zhang 
Cc: Kajol Jain 
Cc: Thomas Richter 
Cc: Palmer Dabbelt 
Link: https://lore.kernel.org/r/20241016062359.264929-7-namhyung@kernel.org
Signed-off-by: Namhyung Kim

perf env: Find correct branch counter info on hybrid

2024-09-11T16:08:46+00:00

No event is printed in the "Branch Counter" column on hybrid machines.

For example,

  $ perf record -e "{cpu_core/branch-instructions/pp,cpu_core/branches/}:S" -j any,counter
  $ perf report --total-cycles

  # Branch counter abbr list:
  # cpu_core/branch-instructions/pp = A
  # cpu_core/branches/ = B
  # '-' No event occurs
  # '+' Event occurrences may be lost due to branch counter saturated
  #
  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles  Branch Counter
  # ...............  ..............  ...........  ..........  ..............
            44.54%          727.1K        0.00%           1   |+   |+   |
            36.31%          592.7K        0.00%           2   |+   |+   |
            17.83%          291.1K        0.00%           1   |+   |+   |

The branch counter information (br_cntr_width and br_cntr_nr) in the
perf_env is retrieved from the CPU_PMU_CAPS. However, the CPU_PMU_CAPS
is not available on hybrid machines. Without the width information, the
number of occurrences of an event cannot be calculated.

For a hybrid machine, the caps information should be retrieved from the
PMU_CAPS, and stored in the perf_env->pmu_caps.

Add a perf_env__find_br_cntr_info() to return the correct branch counter
information from the corresponding fields.

Committer notes:

While testing I couldn't s ee those "Branch counter" columns enabled by
pressing 'B' on the TUI, after reporting it to the list Kan explained
the situation:


For a hybrid client, the "Branch Counter" feature is only supported
starting from the just released Lunar Lake. Perf falls back to only
"ANY" on your Raptor Lake.

The "The branch counter is not available" message is expected.

Here is the 'perf evlist' result from my Lunar Lake machine,

  # perf evlist -v
  cpu_core/branch-instructions/pp: type: 4 (cpu_core), size: 136, config: 0xc4 (branch-instructions), { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|READ|PERIOD|BRANCH_STACK|IDENTIFIER, read_format: ID|GROUP|LOST, disabled: 1, freq: 1, enable_on_exec: 1, precise_ip: 2, sample_id_all: 1, exclude_guest: 1, branch_sample_type: ANY|COUNTERS
  #


Fixes: 6f9d8d1de2c61288 ("perf script: Add branch counters")
Reviewed-by: Ian Rogers 
Signed-off-by: Kan Liang 
Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/r/20240909184201.553519-1-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf env: Avoid recursively taking env->bpf_progs.lock

2024-01-03T20:54:54+00:00

Add variants of perf_env__insert_bpf_prog_info(), perf_env__insert_btf()
and perf_env__find_btf prefixed with __ to indicate the
env->bpf_progs.lock is assumed held.

Call these variants when the lock is held to avoid recursively taking it
and potentially having a thread deadlock with itself.

Fixes: f8dfeae009effc0b ("perf bpf: Show more BPF program info in print_bpf_prog_info()")
Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Acked-by: Song Liu 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Ming Wang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Link: https://lore.kernel.org/r/20231207014655.1252484-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf env: Cache the arch specific strerrno function in perf_env__arch_strerrno()

2023-12-04T19:42:15+00:00

So that we don't have to go thru the series of strcmp(arch) calls for
each id -> string translation.

Reviewed-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: David Laight 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/lkml/20231201203046.486596-3-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf env: Introduce perf_env__arch_strerrno()

2023-12-04T19:42:09+00:00

That will cache the arch specific function translating error numbers to
strings.

Reviewed-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: David Laight 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/lkml/20231201203046.486596-2-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf header: Additional note on AMD IBS for max_precise pmu cap

2023-11-10T11:31:13+00:00

x86 core PMU exposes supported maximum precision level via max_precise
PMU capability. Although, AMD core PMU does not support precise mode,
certain core PMU events with precise_ip > 0 are allowed and forwarded to
IBS OP PMU.

Display a note about this in the 'perf report' header output and
document the details in the perf-list man page.

Signed-off-by: Ravi Bangoria 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ananth Narayan 
Cc: Changbin Du 
Cc: Huacai Chen 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Kim Phillips 
Cc: Mark Rutland 
Cc: Ming Wang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ross Zwisler 
Cc: Sandipan Das 
Cc: Santosh Shukla 
Cc: Yang Jihong 
Link: https://lore.kernel.org/r/20231107083331.901-2-ravi.bangoria@amd.com
Signed-off-by: Arnaldo Carvalho de Melo

perf env: Remove unnecessary NULL tests

2023-10-12T17:01:56+00:00

clang-tidy was warning:
```
util/env.c:334:23: warning: Access to field 'nr_pmu_mappings' results in a dereference of a null pointer (loaded from variable 'env') [clang-analyzer-core.NullDereference]
        env->nr_pmu_mappings = pmu_num;
```

As functions are called potentially when !env was true. This condition
could never be true as it would produce a segv, so remove the
unnecessary NULL tests and silence clang-tidy.

Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Cc: Ravi Bangoria 
Cc: Nick Desaulniers 
Cc: Yang Jihong 
Cc: Huacai Chen 
Cc: Nathan Chancellor 
Cc: Kan Liang 
Cc: llvm@lists.linux.dev
Cc: Ming Wang 
Cc: Tom Rix 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20231009183920.200859-8-irogers@google.com
Signed-off-by: Namhyung Kim

perf pmu: Remove logic for PMU name being NULL

2023-08-25T13:22:16+00:00

The PMU name could be NULL in the case of the fake_pmu. Initialize the
name for the fake_pmu to "fake" so that all other logic can assume it
is initialized. Add a const to the type of name so that a literal can
be used to avoid additional initialization code. Propagate the cost
through related routines and remove now unnecessary "(char *)"
casts. Doing this located a bug in builtin-list for the pmu_glob that
was missing a strdup.

Signed-off-by: Ian Rogers 
Link: https://lore.kernel.org/r/20230825024002.801955-3-irogers@google.com
Cc: K Prateek Nayak 
Cc: Ravi Bangoria 
Cc: James Clark 
Cc: Mark Rutland 
Cc: Suzuki Poulouse 
Cc: Sean Christopherson 
Cc: Wei Li 
Cc: Peter Zijlstra 
Cc: Adrian Hunter 
Cc: Arnaldo Carvalho de Melo 
Cc: Huacai Chen 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Will Deacon 
Cc: Leo Yan 
Cc: Mike Leach 
Cc: Kajol Jain 
Cc: Alexander Shishkin 
Cc: Kan Liang 
Cc: Athira Rajeev 
Cc: linux-arm-kernel@lists.infradead.org
Cc: Ming Wang 
Cc: John Garry 
Cc: Ingo Molnar 
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo