[PATCH v4 16/35] perf pmu: Remove perf_pmu__hybrid_mounted

Ian Rogers
2023-05-26T21:55:51Z

perf_pmu__hybrid_mounted is used to detect whether cpu_core or
cpu_atom is mounted with a non-empty cpus file by
pmu_lookup. Discussion [1] showed the empty cpus file check to be
redundant and so pmu_lookup needn't have a call to
perf_pmu__hybrid_mounted.

Checking hybrid_mounted in pmu_is_uncore is redundant as the next
cpumask read will fail returning false.

Reduce the scope of perf_pmu__find_hybrid_pmu by making it static.

[1] https://lore.kernel.org/lkml/20230524221831.1741381-17-irogers@google.com/

Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
---
tools/perf/util/pmu-hybrid.c | 15 +--------------
tools/perf/util/pmu-hybrid.h | 3 ---
tools/perf/util/pmu.c | 13 +------------
3 files changed, 2 insertions(+), 29 deletions(-)

diff --git a/tools/perf/util/pmu-hybrid.c b/tools/perf/util/pmu-hybrid.c
index bc4cb0738c35..7fe943dd3217 100644
--- a/tools/perf/util/pmu-hybrid.c
+++ b/tools/perf/util/pmu-hybrid.c
@@ -18,20 +18,7 @@

LIST_HEAD(perf_pmu__hybrid_pmus);

-bool perf_pmu__hybrid_mounted(const char *name)
-{
- int cpu;
- char pmu_name[PATH_MAX];
- struct perf_pmu pmu = {.name = pmu_name};
-
- if (strncmp(name, "cpu_", 4))
- return false;
-
- strlcpy(pmu_name, name, sizeof(pmu_name));
- return perf_pmu__scan_file(&pmu, "cpus", "%u", &cpu) > 0;
-}
-
-struct perf_pmu *perf_pmu__find_hybrid_pmu(const char *name)
+static struct perf_pmu *perf_pmu__find_hybrid_pmu(const char *name)
{
struct perf_pmu *pmu;

diff --git a/tools/perf/util/pmu-hybrid.h b/tools/perf/util/pmu-hybrid.h
index 206b94931531..8dbcae935020 100644
--- a/tools/perf/util/pmu-hybrid.h
+++ b/tools/perf/util/pmu-hybrid.h
@@ -13,9 +13,6 @@ extern struct list_head perf_pmu__hybrid_pmus;
#define perf_pmu__for_each_hybrid_pmu(pmu) \
list_for_each_entry(pmu, &perf_pmu__hybrid_pmus, hybrid_list)

-bool perf_pmu__hybrid_mounted(const char *name);
-
-struct perf_pmu *perf_pmu__find_hybrid_pmu(const char *name);
bool perf_pmu__is_hybrid(const char *name);

static inline int perf_pmu__hybrid_pmu_num(void)
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index cd94abe7a87a..83c7eeb8abea 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -617,9 +617,6 @@ static bool pmu_is_uncore(int dirfd, const char *name)
{
int fd;

- if (perf_pmu__hybrid_mounted(name))
- return false;
-
fd = perf_pmu__pathname_fd(dirfd, name, "cpumask", O_PATH);
if (fd < 0)
return false;
@@ -907,15 +904,8 @@ static struct perf_pmu *pmu_lookup(int dirfd, const char *lookup_name)
LIST_HEAD(aliases);
__u32 type;
char *name = pmu_find_real_name(lookup_name);
- bool is_hybrid = perf_pmu__hybrid_mounted(name);
char *alias_name;

- /*
- * Check pmu name for hybrid and the pmu may be invalid in sysfs
- */
- if (!strncmp(name, "cpu_", 4) && !is_hybrid)
- return NULL;
-
/*
* The pmu data we store & need consists of the pmu
* type value and format definitions. Load both right
@@ -936,7 +926,6 @@ static struct perf_pmu *pmu_lookup(int dirfd, const char *lookup_name)

pmu->cpus = pmu_cpumask(dirfd, name);
pmu->name = strdup(name);
-
if (!pmu->name)
goto err;

@@ -967,7 +956,7 @@ static struct perf_pmu *pmu_lookup(int dirfd, const char *lookup_name)
list_splice(&aliases, &pmu->aliases);
list_add_tail(&pmu->list, &pmus);

- if (is_hybrid)
+ if (!strcmp(name, "cpu_core") || !strcmp(name, "cpu_atom"))
list_add_tail(&pmu->hybrid_list, &perf_pmu__hybrid_pmus);
else
INIT_LIST_HEAD(&pmu->hybrid_list);
--
2.41.0.rc0.172.g3f132b7071-goog