Commit 68b741b0 authored by Ian Rogers's avatar Ian Rogers Committed by Junhao He
Browse files

perf pmu: Count sys and cpuid JSON events separately 

mainline inclusion
from mainline-v6.10-rc1
commit d9c5f5f94c2d356fdf3503f7fcaf254512bc032d
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9SXXQ
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d9c5f5f94c2d356fdf3503f7fcaf254512bc032d

--------------------------------

Sys events are eagerly loaded as each event has a compat option that may
mean the event is or isn't associated with the PMU.

These shouldn't be counted as loaded_json_events as that is used for
JSON events matching the CPUID that may or may not have been loaded. The
mismatch causes issues on ARM64 that uses sys events.

Fixes: e6ff1eed ("perf pmu: Lazily add JSON events")
Closes: https://lore.kernel.org/lkml/20240510024729.1075732-1-justin.he@arm.com/


Reported-by: default avatarJia He <justin.he@arm.com>
Signed-off-by: default avatarIan Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240511003601.2666907-1-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarJunhao He <hejunhao3@huawei.com>
parent 5a6a4ae9

tools/perf/util/pmu.c

+48 −20
Original line number Diff line number Diff line
@@ -35,6 +35,18 @@ struct perf_pmu perf_pmu__fake = { 


#define UNIT_MAX_LEN	31 /* max length for event unit name */



enum event_source {

	/* An event loaded from /sys/devices/<pmu>/events. */

	EVENT_SRC_SYSFS,

	/* An event loaded from a CPUID matched json file. */

	EVENT_SRC_CPU_JSON,

	/*

	 * An event loaded from a /sys/devices/<pmu>/identifier matched json

	 * file.

	 */

	EVENT_SRC_SYS_JSON,

};



/**

 * struct perf_pmu_alias - An event either read from sysfs or builtin in

 * pmu-events.c, created by parsing the pmu-events json files.
@@ -499,7 +511,7 @@ static int update_alias(const struct pmu_event *pe, 


static int perf_pmu__new_alias(struct perf_pmu *pmu, const char *name,

				const char *desc, const char *val, FILE *val_fd,

				const struct pmu_event *pe)

			        const struct pmu_event *pe, enum event_source src)

{

	struct perf_pmu_alias *alias;

	int ret;
@@ -551,25 +563,30 @@ static int perf_pmu__new_alias(struct perf_pmu *pmu, const char *name, 
		}

		snprintf(alias->unit, sizeof(alias->unit), "%s", unit);

	}

	if (!pe) {

	switch (src) {

	default:

	case EVENT_SRC_SYSFS:

		alias->from_sysfs = true;

		if (pmu->events_table) {

			/* Update an event from sysfs with json data. */

			struct update_alias_data data = {

				.pmu = pmu,

				.alias = alias,

			};



		alias->from_sysfs = true;

		if (pmu->events_table) {

			if (pmu_events_table__find_event(pmu->events_table, pmu, name,

							 update_alias, &data) == 0)

				pmu->loaded_json_aliases++;

		}

				pmu->cpu_json_aliases++;

		}



	if (!pe)

		pmu->sysfs_aliases++;

	else

		pmu->loaded_json_aliases++;

		break;

	case  EVENT_SRC_CPU_JSON:

		pmu->cpu_json_aliases++;

		break;

	case  EVENT_SRC_SYS_JSON:

		pmu->sys_json_aliases++;

		break;



	}

	list_add_tail(&alias->list, &pmu->aliases);

	return 0;

}
@@ -645,7 +662,8 @@ static int pmu_aliases_parse(struct perf_pmu *pmu) 
		}



		if (perf_pmu__new_alias(pmu, name, /*desc=*/ NULL,

					/*val=*/ NULL, file, /*pe=*/ NULL) < 0)

					/*val=*/ NULL, file, /*pe=*/ NULL,

					EVENT_SRC_SYSFS) < 0)

			pr_debug("Cannot set up %s\n", name);

		fclose(file);

	}
@@ -880,7 +898,8 @@ static int pmu_add_cpu_aliases_map_callback(const struct pmu_event *pe, 
{

	struct perf_pmu *pmu = vdata;



	perf_pmu__new_alias(pmu, pe->name, pe->desc, pe->event, /*val_fd=*/ NULL, pe);

	perf_pmu__new_alias(pmu, pe->name, pe->desc, pe->event, /*val_fd=*/ NULL,

			    pe, EVENT_SRC_CPU_JSON);

	return 0;

}
@@ -921,7 +940,8 @@ static int pmu_add_sys_aliases_iter_fn(const struct pmu_event *pe, 
				pe->desc,

				pe->event,

				/*val_fd=*/ NULL,

				pe);

				pe,

				EVENT_SRC_SYS_JSON);

	}



	return 0;
@@ -1011,6 +1031,12 @@ struct perf_pmu *perf_pmu__lookup(struct list_head *pmus, int dirfd, const char 
		pmu->id = pmu_id(name);

	pmu->max_precise = pmu_max_precise(dirfd, pmu);

	pmu->events_table = perf_pmu__find_events_table(pmu);

	/*

	 * Load the sys json events/aliases when loading the PMU as each event

	 * may have a different compat regular expression. We therefore can't

	 * know the number of sys json events/aliases without computing the

	 * regular expressions for them all.

	 */

	pmu_add_sys_aliases(pmu);

	list_add_tail(&pmu->list, pmus);
@@ -1607,12 +1633,14 @@ size_t perf_pmu__num_events(struct perf_pmu *pmu) 
	if (!pmu->sysfs_aliases_loaded)

		pmu_aliases_parse(pmu);



	nr = pmu->sysfs_aliases;

	nr = pmu->sysfs_aliases + pmu->sys_json_aliases;;



	if (pmu->cpu_aliases_added)

		 nr += pmu->loaded_json_aliases;

		 nr += pmu->cpu_json_aliases;

	else if (pmu->events_table)

		nr += pmu_events_table__num_events(pmu->events_table, pmu) - pmu->loaded_json_aliases;

		nr += pmu_events_table__num_events(pmu->events_table, pmu) - pmu->cpu_json_aliases;

	else

		assert(pmu->cpu_json_aliases == 0);



	return pmu->selectable ? nr + 1 : nr;

}

tools/perf/util/pmu.h

+4 −2
Original line number Diff line number Diff line
@@ -120,8 +120,10 @@ struct perf_pmu { 
	const struct pmu_events_table *events_table;

	/** @sysfs_aliases: Number of sysfs aliases loaded. */

	uint32_t sysfs_aliases;

	/** @sysfs_aliases: Number of json event aliases loaded. */

	uint32_t loaded_json_aliases;

	/** @cpu_json_aliases: Number of json event aliases loaded specific to the CPUID. */

	uint32_t cpu_json_aliases;

	/** @sys_json_aliases: Number of json event aliases loaded matching the PMU's identifier. */

	uint32_t sys_json_aliases;

	/** @sysfs_aliases_loaded: Are sysfs aliases loaded from disk? */

	bool sysfs_aliases_loaded;

	/**