perf header: Record non-CPU PMU capabilities

PMUs advertise their capabilities via sysfs attribute files but
the perf tool currently parses only core(CPU) or hybrid core PMU
capabilities. Add support of recording non-core PMU capabilities
int perf.data header.

Note that a newly proposed HEADER_PMU_CAPS is replacing existing
HEADER_HYBRID_CPU_PMU_CAPS. Special care is taken for hybrid core
PMUs by writing their capabilities first in the perf.data header
to make sure new perf.data file being read by old perf tool does
not break.

Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ananth Narayan <ananth.narayan@amd.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <rrichter@amd.com>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: like.xu.linux@gmail.com
Cc: x86@kernel.org
Link: https://lore.kernel.org/r/20220604044519.594-6-ravi.bangoria@amd.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 54 insertions, 6 deletions

diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index 7d3aeb2e4622..5b8cf6a421a4 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -219,13 +219,13 @@ void perf_env__exit(struct perf_env *env)
 	}
 	zfree(&env->hybrid_nodes);
 
-	for (i = 0; i < env->nr_hybrid_cpc_nodes; i++) {
-		for (j = 0; j < env->hybrid_cpc_nodes[i].nr_cpu_pmu_caps; j++)
-			zfree(&env->hybrid_cpc_nodes[i].cpu_pmu_caps[j]);
-		zfree(&env->hybrid_cpc_nodes[i].cpu_pmu_caps);
-		zfree(&env->hybrid_cpc_nodes[i].pmu_name);
+	for (i = 0; i < env->nr_pmus_with_caps; i++) {
+		for (j = 0; j < env->pmu_caps[i].nr_caps; j++)
+			zfree(&env->pmu_caps[i].caps[j]);
+		zfree(&env->pmu_caps[i].caps);
+		zfree(&env->pmu_caps[i].pmu_name);
 	}
-	zfree(&env->hybrid_cpc_nodes);
+	zfree(&env->pmu_caps);
 }
 
 void perf_env__init(struct perf_env *env)
@@ -531,3 +531,51 @@ int perf_env__numa_node(struct perf_env *env, struct perf_cpu cpu)
 
 	return cpu.cpu >= 0 && cpu.cpu < env->nr_numa_map ? env->numa_map[cpu.cpu] : -1;
 }
+
+char *perf_env__find_pmu_cap(struct perf_env *env, const char *pmu_name,
+			     const char *cap)
+{
+	char *cap_eq;
+	int cap_size;
+	char **ptr;
+	int i, j;
+
+	if (!pmu_name || !cap)
+		return NULL;
+
+	cap_size = strlen(cap);
+	cap_eq = zalloc(cap_size + 2);
+	if (!cap_eq)
+		return NULL;
+
+	memcpy(cap_eq, cap, cap_size);
+	cap_eq[cap_size] = '=';
+
+	if (!strcmp(pmu_name, "cpu")) {
+		for (i = 0; i < env->nr_cpu_pmu_caps; i++) {
+			if (!strncmp(env->cpu_pmu_caps[i], cap_eq, cap_size + 1)) {
+				free(cap_eq);
+				return &env->cpu_pmu_caps[i][cap_size + 1];
+			}
+		}
+		goto out;
+	}
+
+	for (i = 0; i < env->nr_pmus_with_caps; i++) {
+		if (strcmp(env->pmu_caps[i].pmu_name, pmu_name))
+			continue;
+
+		ptr = env->pmu_caps[i].caps;
+
+		for (j = 0; j < env->pmu_caps[i].nr_caps; j++) {
+			if (!strncmp(ptr[j], cap_eq, cap_size + 1)) {
+				free(cap_eq);
+				return &ptr[j][cap_size + 1];
+			}
+		}
+	}
+
+out:
+	free(cap_eq);
+	return NULL;
+}