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Jin Yao 8adc0a06d6 perf script: Fix overrun issue for dynamically-allocated PMU type number

When unpacking the event which is from dynamic PMU, the array
output[OUTPUT_TYPE_MAX] may be overrun. For example, type number of SKL
uncore_imc is 10, but OUTPUT_TYPE_MAX is 7 now (OUTPUT_TYPE_MAX =
PERF_TYPE_MAX + 1).

/* In builtin-script.c */

process_event()
{
        unsigned int type = output_type(attr->type);

        if (output[type].fields == 0)
                return;
}

output[10] is overrun.

Create a type OUTPUT_TYPE_OTHER for dynamic PMU events, then
output_type(attr->type) will return OUTPUT_TYPE_OTHER here.

Note that if PERF_TYPE_MAX ever changed, then there would be a conflict
between old perf.data files that had a dynamicaliy allocated PMU number
that would then be the same as a fixed PERF_TYPE.

Example:

  # perf record --switch-events -C 0 -e "{cpu-clock,uncore_imc/data_reads/,uncore_imc/data_writes/}:SD" -a -- sleep 1
  # perf script

  Before:
         swapper     0 [000] 1479253.987551:     277766               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.987797:     246709               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.988127:     329883               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.988273:     146393               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.988523:     249977               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.988877:     354090               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.989023:     145940               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.989383:     359856               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1479253.989523:     140082               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])

  After:
         swapper     0 [000] 1397040.402011:     272384               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1397040.402011:       5396  uncore_imc/data_reads/:
         swapper     0 [000] 1397040.402011:        967 uncore_imc/data_writes/:
         swapper     0 [000] 1397040.402259:     249153               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1397040.402259:       7231  uncore_imc/data_reads/:
         swapper     0 [000] 1397040.402259:       1297 uncore_imc/data_writes/:
         swapper     0 [000] 1397040.402508:     249108               cpu-clock:  ffffffff9d4ddb6f cpuidle_enter_state+0xdf ([kernel.kallsyms])
         swapper     0 [000] 1397040.402508:       5333  uncore_imc/data_reads/:
         swapper     0 [000] 1397040.402508:       1008 uncore_imc/data_writes/:

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/r/20201209005828.21302-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2021-01-21 17:25:33 -03:00

arch

perf tools: Update s390's syscall.tbl copy from the kernel sources

2020-12-24 09:24:20 -03:00

bench

…

Documentation

perf sort: Add sort option for data page size

2020-12-19 17:52:24 -03:00

examples/bpf

perf bpf examples: Fix bpf.h header include directive in 5sec.c example

2021-01-15 16:31:46 -03:00