Commit 4cb7d3ec authored by Thomas Richter's avatar Thomas Richter Committed by Arnaldo Carvalho de Melo
Browse files

perf cpuid: Introduce a platform specific cpuid compare function 



The function get_cpuid_str() is called by perf_pmu__getcpuid() and on
s390 returns a complete description of the CPU and its capabilities,
which is a comma separated list.

To map the CPU type with the value defined in the
pmu-events/arch/s390/mapfile.csv, introduce an architecture specific
cpuid compare function named strcmp_cpuid_str()

The currently used regex algorithm is defined as the weak default and
will be used if no platform specific one is defined. This matches the
current behavior.

Signed-off-by: default avatarThomas Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: default avatarHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180213151419.80737-3-tmricht@linux.vnet.ibm.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent c59124fa

tools/perf/arch/s390/util/header.c

+18 −0
Original line number Diff line number Diff line
@@ -146,3 +146,21 @@ char *get_cpuid_str(struct perf_pmu *pmu __maybe_unused) 
		zfree(&buf);

	return buf;

}



/*

 * Compare the cpuid string returned by get_cpuid() function

 * with the name generated by the jevents file read from

 * pmu-events/arch/s390/mapfile.csv.

 *

 * Parameter mapcpuid is the cpuid as stored in the

 * pmu-events/arch/s390/mapfile.csv. This is just the type number.

 * Parameter cpuid is the cpuid returned by function get_cpuid().

 */

int strcmp_cpuid_str(const char *mapcpuid, const char *cpuid)

{

	char *cp = strchr(cpuid, ',');



	if (cp == NULL)

		return -1;

	return strncmp(cp + 1, mapcpuid, strlen(mapcpuid));

}

tools/perf/util/header.h

+1 −0
Original line number Diff line number Diff line
@@ -174,4 +174,5 @@ int write_padded(struct feat_fd *fd, const void *bf, 
int get_cpuid(char *buffer, size_t sz);



char *get_cpuid_str(struct perf_pmu *pmu __maybe_unused);

int strcmp_cpuid_str(const char *s1, const char *s2);

#endif /* __PERF_HEADER_H */

tools/perf/util/pmu.c

+29 −18
Original line number Diff line number Diff line
@@ -576,6 +576,34 @@ char * __weak get_cpuid_str(struct perf_pmu *pmu __maybe_unused) 
	return NULL;

}



/* Return zero when the cpuid from the mapfile.csv matches the

 * cpuid string generated on this platform.

 * Otherwise return non-zero.

 */

int __weak strcmp_cpuid_str(const char *mapcpuid, const char *cpuid)

{

	regex_t re;

	regmatch_t pmatch[1];

	int match;



	if (regcomp(&re, mapcpuid, REG_EXTENDED) != 0) {

		/* Warn unable to generate match particular string. */

		pr_info("Invalid regular expression %s\n", mapcpuid);

		return 1;

	}



	match = !regexec(&re, cpuid, 1, pmatch, 0);

	regfree(&re);

	if (match) {

		size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so);



		/* Verify the entire string matched. */

		if (match_len == strlen(cpuid))

			return 0;

	}

	return 1;

}



static char *perf_pmu__getcpuid(struct perf_pmu *pmu)

{

	char *cpuid;
@@ -610,32 +638,15 @@ struct pmu_events_map *perf_pmu__find_map(struct perf_pmu *pmu) 


	i = 0;

	for (;;) {

		regex_t re;

		regmatch_t pmatch[1];

		int match;



		map = &pmu_events_map[i++];

		if (!map->table) {

			map = NULL;

			break;

		}



		if (regcomp(&re, map->cpuid, REG_EXTENDED) != 0) {

			/* Warn unable to generate match particular string. */

			pr_info("Invalid regular expression %s\n", map->cpuid);

		if (!strcmp_cpuid_str(map->cpuid, cpuid))

			break;

	}



		match = !regexec(&re, cpuid, 1, pmatch, 0);

		regfree(&re);

		if (match) {

			size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so);



			/* Verify the entire string matched. */

			if (match_len == strlen(cpuid))

				break;

		}

	}

	free(cpuid);

	return map;

}

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