mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-05 18:39:59 +00:00
Code Issues Releases Wiki Activity

perf pmu: Add helper function is_pmu_core to detect PMU CORE devices

Browse source 
On some platforms, PMU core devices sysfs name is not cpu.
Adding function is_pmu_core to detect PMU core devices using
core device specific hints in sysfs.

For arm64 platforms, all core devices have file "cpus" in sysfs.

Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Tested-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/n/tip-y1woxt1k2pqqwpprhonnft2s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Ganapatrao Kulkarni 2017-08-24 16:30:58 +05:30 committed by Arnaldo Carvalho de Melo
parent b57df28893
commit 14b22ae028
1 changed files with 35 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

39
tools/perf/util/pmu.c
View file

@ -536,6 +536,34 @@ static bool pmu_is_uncore(const char *name)
return !!cpus;
}
/*
* PMU CORE devices have different name other than cpu in sysfs on some
* platforms. looking for possible sysfs files to identify as core device.
*/
static int is_pmu_core(const char *name)
{
struct stat st;
char path[PATH_MAX];
const char *sysfs = sysfs__mountpoint();
if (!sysfs)
return 0;
/* Look for cpu sysfs (x86 and others) */
scnprintf(path, PATH_MAX, "%s/bus/event_source/devices/cpu", sysfs);
if ((stat(path, &st) == 0) &&
(strncmp(name, "cpu", strlen("cpu")) == 0))
return 1;
/* Look for cpu sysfs (specific to arm) */
scnprintf(path, PATH_MAX, "%s/bus/event_source/devices/%s/cpus",
sysfs, name);
if (stat(path, &st) == 0)
return 1;
return 0;
}
/*
* Return the CPU id as a raw string.
*
@ -609,7 +637,6 @@ static void pmu_add_cpu_aliases(struct list_head *head, struct perf_pmu *pmu)
*/
i = 0;
while (1) {
const char *pname;
pe = &map->table[i++];
if (!pe->name) {
@ -618,9 +645,13 @@ static void pmu_add_cpu_aliases(struct list_head *head, struct perf_pmu *pmu)
break;
}
pname = pe->pmu ? pe->pmu : "cpu";
if (strncmp(pname, name, strlen(pname)))
continue;
if (!is_pmu_core(name)) {
/* check for uncore devices */
if (pe->pmu == NULL)
continue;
if (strncmp(pe->pmu, name, strlen(pe->pmu)))
continue;
}
/* need type casts to override 'const' */
__perf_pmu__new_alias(head, NULL, (char *)pe->name,