Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
perf pmu: Tolerate failure to read the type for wellknown PMUs
If sysfs isn't mounted then we may fail to read a PMU's type. In this
situation resort to lookup of wellknown types. Only applies to
software, tracepoint and breakpoint PMUs.
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250710235126.1086011-5-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
authored by
Ian Rogers
and committed by
Namhyung Kim
8c75dc74
bcc7693a
+32
-2
+32
-2
tools/perf/util/pmu.c
+32
-2
tools/perf/util/pmu.c
···
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return 0;
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}
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static __u32 wellknown_pmu_type(const char *pmu_name)
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{
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struct {
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const char *pmu_name;
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__u32 type;
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} wellknown_pmus[] = {
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{
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"software",
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PERF_TYPE_SOFTWARE
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},
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{
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"tracepoint",
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PERF_TYPE_TRACEPOINT
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},
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{
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"breakpoint",
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PERF_TYPE_BREAKPOINT
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},
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};
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for (size_t i = 0; i < ARRAY_SIZE(wellknown_pmus); i++) {
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if (!strcmp(wellknown_pmus[i].pmu_name, pmu_name))
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return wellknown_pmus[i].type;
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}
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return PERF_TYPE_MAX;
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}
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struct perf_pmu *perf_pmu__lookup(struct list_head *pmus, int dirfd, const char *name,
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bool eager_load)
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{
···
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* that type value is successfully assigned (return 1).
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*/
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if (perf_pmu__scan_file_at(pmu, dirfd, "type", "%u", &pmu->type) != 1) {
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-
perf_pmu__delete(pmu);
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-
return NULL;
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/* Double check the PMU's name isn't wellknown. */
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pmu->type = wellknown_pmu_type(name);
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if (pmu->type == PERF_TYPE_MAX) {
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perf_pmu__delete(pmu);
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return NULL;
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}
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}
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/*