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Author SHA1 Message Date
Like Xu
4da8b12188 perf iostat: Fix Segmentation fault from NULL 'struct perf_counts_values *'
If the 'perf iostat' user specifies two or more iio_root_ports and also
specifies the cpu(s) by -C which is not *connected to all* the above iio
ports, the iostat_print_metric() will run into trouble:

For example:

  $ perf iostat list
  S0-uncore_iio_0<0000:16>
  S1-uncore_iio_0<0000:97> # <--- CPU 1 is located in the socket S0

  $ perf iostat 0000:16,0000:97 -C 1 -- ls
  port 	Inbound Read(MB)	Inbound Write(MB)	Outbound Read(MB)	Outbound
  Write(MB) ../perf-iostat: line 12: 104418 Segmentation fault
  (core dumped) perf stat --iostat$DELIMITER$*

The core-dump stack says, in the above corner case, the returned
(struct perf_counts_values *) count will be NULL, and the caller
iostat_print_metric() apparently doesn't not handle this case.

  433	struct perf_counts_values *count = perf_counts(evsel->counts, die, 0);
  434
  435	if (count->run && count->ena) {
  (gdb) p count
  $1 = (struct perf_counts_values *) 0x0

The deeper reason is that there are actually no statistics from the user
specified pair "iostat 0000:X, -C (disconnected) Y ", but let's fix it with
minimum cost by adding a NULL check in the user space.

Fixes: f9ed693e8b ("perf stat: Enable iostat mode for x86 platforms")
Signed-off-by: Like Xu <likexu@tencent.com>
Cc: Alexander Antonov <alexander.antonov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210927081115.39568-2-likexu@tencent.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-09-27 09:41:07 -03:00
Jiri Olsa
38fe0e0156 libperf: Move 'idx' from tools/perf to perf_evsel::idx
Move evsel::idx to perf_evsel::idx, so we can move the group interface
to libperf.

Committer notes:

Fixup evsel->idx usage in tools/perf/util/bpf_counter_cgroup.c, that
appeared in my tree in my local tree.

Also fixed up these:

$ find tools/perf/ -name "*.[ch]" | xargs grep 'evsel->idx'
tools/perf/ui/gtk/annotate.c:                      evsel->idx + i);
tools/perf/ui/gtk/annotate.c:                   evsel->idx);
$

That running 'make -C tools/perf build-test' caught.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Requested-by: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210706151704.73662-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-07-09 14:04:28 -03:00
Alexander Antonov
f9ed693e8b perf stat: Enable iostat mode for x86 platforms
This functionality is based on recently introduced sysfs attributes for
Intel® Xeon® Scalable processor family (code name Skylake-SP):

Commit bb42b3d397 ("perf/x86/intel/uncore: Expose an Uncore unit to IIO PMON mapping")

Mode is intended to provide four I/O performance metrics in MB per each
PCIe root port:

 - Inbound Read: I/O devices below root port read from the host memory
 - Inbound Write: I/O devices below root port write to the host memory
 - Outbound Read: CPU reads from I/O devices below root port
 - Outbound Write: CPU writes to I/O devices below root port

Each metric requiries only one uncore event which increments at every 4B
transfer in corresponding direction. The formulas to compute metrics
are generic:
    #EventCount * 4B / (1024 * 1024)

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey V Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210419094147.15909-4-alexander.antonov@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-04-20 08:40:20 -03:00
Alexander Antonov
19776d3ced perf stat: Helper functions for PCIe root ports list in iostat mode
Introduce helper functions to control PCIe root ports list.
These helpers will be used in the follow-up patch.

Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey V Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210419094147.15909-3-alexander.antonov@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-04-20 08:40:20 -03:00