[PATCH v2 2/8] perf tools: Support pmu prefix for mem-load event

From: Jin Yao
Date: Thu May 27 2021 - 03:54:45 EST


The perf_mem_events__name() can generate the mem-load event name.
It uses a variable 'mem_loads_name__init' to avoid generating the
event name every time (because perf_pmu__scan takes some time).

The perf_mem_events__name() assumes the pmu is "cpu" but it's not
correct for hybrid platform. For Alderlake, the pmu is "cpu_core" or
"cpu_atom"

Introduce a new parameter 'pmu_name' in perf_mem_events__name
to let the caller specify a pmu name.

Considering such event name is x86 specific, so move
perf_mem_events[] to arch/x86/util/mem-events.c.

We still keep the variable 'mem_loads_name__init' but it's only
used when pmu_name is NULL (compatible for original behavior). When
pmu_name is not NULL (e.g. "cpu_core"), this patch doesn't have
optimization. That can be implemented in follow up patch.

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
v2:
- Move perf_mem_events[] to x86 specific file.
- Create x86 specific perf_mem_events__ptr().
- Use mem_loads_name__init for keeping original behavior
on non-hybrid platform.

tools/perf/arch/arm64/util/mem-events.c | 2 +-
tools/perf/arch/powerpc/util/mem-events.c | 2 +-
tools/perf/arch/x86/util/mem-events.c | 35 ++++++++++++++++++-----
tools/perf/builtin-c2c.c | 4 +--
tools/perf/builtin-mem.c | 4 +--
tools/perf/util/mem-events.c | 4 +--
tools/perf/util/mem-events.h | 2 +-
7 files changed, 37 insertions(+), 16 deletions(-)

diff --git a/tools/perf/arch/arm64/util/mem-events.c b/tools/perf/arch/arm64/util/mem-events.c
index 2a2497372671..be41721b9aa1 100644
--- a/tools/perf/arch/arm64/util/mem-events.c
+++ b/tools/perf/arch/arm64/util/mem-events.c
@@ -20,7 +20,7 @@ struct perf_mem_event *perf_mem_events__ptr(int i)
return &perf_mem_events[i];
}

-char *perf_mem_events__name(int i)
+char *perf_mem_events__name(int i, char *pmu_name __maybe_unused)
{
struct perf_mem_event *e = perf_mem_events__ptr(i);

diff --git a/tools/perf/arch/powerpc/util/mem-events.c b/tools/perf/arch/powerpc/util/mem-events.c
index 07fb5e049488..4120fafe0be4 100644
--- a/tools/perf/arch/powerpc/util/mem-events.c
+++ b/tools/perf/arch/powerpc/util/mem-events.c
@@ -3,7 +3,7 @@
#include "mem-events.h"

/* PowerPC does not support 'ldlat' parameter. */
-char *perf_mem_events__name(int i)
+char *perf_mem_events__name(int i, char *pmu_name __maybe_unused)
{
if (i == PERF_MEM_EVENTS__LOAD)
return (char *) "cpu/mem-loads/";
diff --git a/tools/perf/arch/x86/util/mem-events.c b/tools/perf/arch/x86/util/mem-events.c
index e79232e3f2a0..f9e444a4fe70 100644
--- a/tools/perf/arch/x86/util/mem-events.c
+++ b/tools/perf/arch/x86/util/mem-events.c
@@ -7,7 +7,23 @@ static char mem_loads_name[100];
static bool mem_loads_name__init;

#define MEM_LOADS_AUX 0x8203
-#define MEM_LOADS_AUX_NAME "{cpu/mem-loads-aux/,cpu/mem-loads,ldlat=%u/pp}:S"
+#define MEM_LOADS_AUX_NAME "{%s/mem-loads-aux/,%s/mem-loads,ldlat=%u/}:P"
+
+#define E(t, n, s) { .tag = t, .name = n, .sysfs_name = s }
+
+static struct perf_mem_event perf_mem_events[PERF_MEM_EVENTS__MAX] = {
+ E("ldlat-loads", "%s/mem-loads,ldlat=%u/P", "%s/events/mem-loads"),
+ E("ldlat-stores", "cpu/mem-stores/P", "cpu/events/mem-stores"),
+ E(NULL, NULL, NULL),
+};
+
+struct perf_mem_event *perf_mem_events__ptr(int i)
+{
+ if (i >= PERF_MEM_EVENTS__MAX)
+ return NULL;
+
+ return &perf_mem_events[i];
+}

bool is_mem_loads_aux_event(struct evsel *leader)
{
@@ -22,7 +38,7 @@ bool is_mem_loads_aux_event(struct evsel *leader)
return leader->core.attr.config == MEM_LOADS_AUX;
}

-char *perf_mem_events__name(int i)
+char *perf_mem_events__name(int i, char *pmu_name)
{
struct perf_mem_event *e = perf_mem_events__ptr(i);

@@ -30,17 +46,22 @@ char *perf_mem_events__name(int i)
return NULL;

if (i == PERF_MEM_EVENTS__LOAD) {
- if (mem_loads_name__init)
+ if (mem_loads_name__init && !pmu_name)
return mem_loads_name;

- mem_loads_name__init = true;
+ if (!pmu_name) {
+ mem_loads_name__init = true;
+ pmu_name = (char *)"cpu";
+ }

- if (pmu_have_event("cpu", "mem-loads-aux")) {
+ if (pmu_have_event(pmu_name, "mem-loads-aux")) {
scnprintf(mem_loads_name, sizeof(mem_loads_name),
- MEM_LOADS_AUX_NAME, perf_mem_events__loads_ldlat);
+ MEM_LOADS_AUX_NAME, pmu_name, pmu_name,
+ perf_mem_events__loads_ldlat);
} else {
scnprintf(mem_loads_name, sizeof(mem_loads_name),
- e->name, perf_mem_events__loads_ldlat);
+ e->name, pmu_name,
+ perf_mem_events__loads_ldlat);
}
return mem_loads_name;
}
diff --git a/tools/perf/builtin-c2c.c b/tools/perf/builtin-c2c.c
index e3b9d63077ef..a4fd375acdd1 100644
--- a/tools/perf/builtin-c2c.c
+++ b/tools/perf/builtin-c2c.c
@@ -2971,13 +2971,13 @@ static int perf_c2c__record(int argc, const char **argv)

if (!e->supported) {
pr_err("failed: event '%s' not supported\n",
- perf_mem_events__name(j));
+ perf_mem_events__name(j, NULL));
free(rec_argv);
return -1;
}

rec_argv[i++] = "-e";
- rec_argv[i++] = perf_mem_events__name(j);
+ rec_argv[i++] = perf_mem_events__name(j, NULL);
}

if (all_user)
diff --git a/tools/perf/builtin-mem.c b/tools/perf/builtin-mem.c
index cdd2b9f643f6..03795bf49d51 100644
--- a/tools/perf/builtin-mem.c
+++ b/tools/perf/builtin-mem.c
@@ -135,13 +135,13 @@ static int __cmd_record(int argc, const char **argv, struct perf_mem *mem)

if (!e->supported) {
pr_err("failed: event '%s' not supported\n",
- perf_mem_events__name(j));
+ perf_mem_events__name(j, NULL));
free(rec_argv);
return -1;
}

rec_argv[i++] = "-e";
- rec_argv[i++] = perf_mem_events__name(j);
+ rec_argv[i++] = perf_mem_events__name(j, NULL);
}

if (all_user)
diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index f93a852ad838..c736eaded06c 100644
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c
@@ -37,7 +37,7 @@ struct perf_mem_event * __weak perf_mem_events__ptr(int i)
return &perf_mem_events[i];
}

-char * __weak perf_mem_events__name(int i)
+char * __weak perf_mem_events__name(int i, char *pmu_name __maybe_unused)
{
struct perf_mem_event *e = perf_mem_events__ptr(i);

@@ -141,7 +141,7 @@ void perf_mem_events__list(void)
fprintf(stderr, "%-13s%-*s%s\n",
e->tag ?: "",
verbose > 0 ? 25 : 0,
- verbose > 0 ? perf_mem_events__name(j) : "",
+ verbose > 0 ? perf_mem_events__name(j, NULL) : "",
e->supported ? ": available" : "");
}
}
diff --git a/tools/perf/util/mem-events.h b/tools/perf/util/mem-events.h
index cacdebd65b8a..a3fa19093fd2 100644
--- a/tools/perf/util/mem-events.h
+++ b/tools/perf/util/mem-events.h
@@ -38,7 +38,7 @@ extern unsigned int perf_mem_events__loads_ldlat;
int perf_mem_events__parse(const char *str);
int perf_mem_events__init(void);

-char *perf_mem_events__name(int i);
+char *perf_mem_events__name(int i, char *pmu_name);
struct perf_mem_event *perf_mem_events__ptr(int i);
bool is_mem_loads_aux_event(struct evsel *leader);

--
2.17.1