perf pmu: Save detected hybrid pmus to a global pmu list

We identify the cpu_core pmu and cpu_atom pmu by explicitly
checking following files:

For cpu_core, checks:
"/sys/bus/event_source/devices/cpu_core/cpus"

For cpu_atom, checks:
"/sys/bus/event_source/devices/cpu_atom/cpus"

If the 'cpus' file exists and it has data, the pmu exists.

But in order not to hardcode the "cpu_core" and "cpu_atom",
and make the code in a generic way.

So if the path "/sys/bus/event_source/devices/cpu_xxx/cpus" exists, the
hybrid pmu exists. All the detected hybrid pmus are linked to a global
list 'perf_pmu__hybrid_pmus' and then next we just need to iterate the
list to get all hybrid pmu by using perf_pmu__for_each_hybrid_pmu.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210427070139.25256-6-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 44225838eb039..6e49c7b8ad71f 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -25,6 +25,7 @@
 #include "string2.h"
 #include "strbuf.h"
 #include "fncache.h"
+#include "pmu-hybrid.h"
 
 struct perf_pmu perf_pmu__fake;
 
@@ -613,7 +614,6 @@ static struct perf_cpu_map *__pmu_cpumask(const char *path)
  */
 #define SYS_TEMPLATE_ID	"./bus/event_source/devices/%s/identifier"
 #define CPUS_TEMPLATE_UNCORE	"%s/bus/event_source/devices/%s/cpumask"
-#define CPUS_TEMPLATE_CPU	"%s/bus/event_source/devices/%s/cpus"
 
 static struct perf_cpu_map *pmu_cpumask(const char *name)
 {
@@ -645,6 +645,9 @@ static bool pmu_is_uncore(const char *name)
 	char path[PATH_MAX];
 	const char *sysfs;
 
+	if (perf_pmu__hybrid_mounted(name))
+		return false;
+
 	sysfs = sysfs__mountpoint();
 	snprintf(path, PATH_MAX, CPUS_TEMPLATE_UNCORE, sysfs, name);
 	return file_available(path);
@@ -951,6 +954,7 @@ static struct perf_pmu *pmu_lookup(const char *name)
 	pmu->is_uncore = pmu_is_uncore(name);
 	if (pmu->is_uncore)
 		pmu->id = pmu_id(name);
+	pmu->is_hybrid = perf_pmu__hybrid_mounted(name);
 	pmu->max_precise = pmu_max_precise(name);
 	pmu_add_cpu_aliases(&aliases, pmu);
 	pmu_add_sys_aliases(&aliases, pmu);
@@ -962,6 +966,9 @@ static struct perf_pmu *pmu_lookup(const char *name)
 	list_splice(&aliases, &pmu->aliases);
 	list_add_tail(&pmu->list, &pmus);
 
+	if (pmu->is_hybrid)
+		list_add_tail(&pmu->hybrid_list, &perf_pmu__hybrid_pmus);
+
 	pmu->default_config = perf_pmu__get_default_config(pmu);
 
 	return pmu;