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perf script: Fix overrun issue for dynamically-allocated PMU type number
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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 <[email protected]>
Acked-by: Adrian Hunter <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Jin Yao authored and acmel committed Jan 21, 2021
1 parent 3d6e79e commit 8adc0a0
Showing 1 changed file with 17 additions and 1 deletion.
18 changes: 17 additions & 1 deletion tools/perf/builtin-script.c
Original file line number Diff line number Diff line change
Expand Up @@ -186,6 +186,7 @@ struct output_option {

enum {
OUTPUT_TYPE_SYNTH = PERF_TYPE_MAX,
OUTPUT_TYPE_OTHER,
OUTPUT_TYPE_MAX
};

Expand Down Expand Up @@ -283,6 +284,18 @@ static struct {

.invalid_fields = PERF_OUTPUT_TRACE | PERF_OUTPUT_BPF_OUTPUT,
},

[OUTPUT_TYPE_OTHER] = {
.user_set = false,

.fields = PERF_OUTPUT_COMM | PERF_OUTPUT_TID |
PERF_OUTPUT_CPU | PERF_OUTPUT_TIME |
PERF_OUTPUT_EVNAME | PERF_OUTPUT_IP |
PERF_OUTPUT_SYM | PERF_OUTPUT_SYMOFFSET |
PERF_OUTPUT_DSO | PERF_OUTPUT_PERIOD,

.invalid_fields = PERF_OUTPUT_TRACE | PERF_OUTPUT_BPF_OUTPUT,
},
};

struct evsel_script {
Expand Down Expand Up @@ -343,8 +356,11 @@ static inline int output_type(unsigned int type)
case PERF_TYPE_SYNTH:
return OUTPUT_TYPE_SYNTH;
default:
return type;
if (type < PERF_TYPE_MAX)
return type;
}

return OUTPUT_TYPE_OTHER;
}

static inline unsigned int attr_type(unsigned int type)
Expand Down

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