[PATCH 37/49] perf parse-events: Support hardware events inside PMU

From: kan . liang
Date: Mon Feb 08 2021 - 13:08:32 EST


From: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>

On hybrid platform, some hardware cache events are only available
on a specific pmu. For example, 'L1-dcache-load-misses' is only
available on 'cpu_core' pmu. And even for the event which can be
available on both pmus, the user also may want to just enable
one event. So now following syntax is supported:

cpu_core/<hardware event>/
cpu_core/<hardware cache event>/
cpu_core/<pmu event>/

cpu_atom/<hardware event>/
cpu_atom/<hardware cache event>/
cpu_atom/<pmu event>/

It limits the event to be enabled only on a specified pmu.

The patch uses this idea, for example, if we use "cpu_core/LLC-loads/",
in parse_events_add_pmu(), term->config is "LLC-loads".

We create a new "parse_events_state" with the pmu_name and use
parse_events__scanner to scan the term->config (the string "LLC-loads"
in this example). The parse_events_add_cache() will be called during
parsing. The parse_state->pmu_name is used to identify the pmu
where the event is enabled.

For example,

root@otcpl-adl-s-2:~# ./perf stat -e cpu_core/cycles/,cpu_core/LLC-loads/ -vv -- ./triad_loop
Control descriptor is not initialized
------------------------------------------------------------
perf_event_attr:
type 6
size 120
config 0x400000000
sample_type IDENTIFIER
read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
disabled 1
inherit 1
enable_on_exec 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid 29207 cpu -1 group_fd -1 flags 0x8 = 3
------------------------------------------------------------
perf_event_attr:
type 7
size 120
config 0x400000002
sample_type IDENTIFIER
read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
disabled 1
inherit 1
enable_on_exec 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid 29207 cpu -1 group_fd -1 flags 0x8 = 4
cycles: 0: 401363820 101974864 101974864
LLC-loads: 0: 2577 101974864 101974864
cycles: 401363820 101974864 101974864
LLC-loads: 2577 101974864 101974864

Performance counter stats for './triad_loop':

401,363,820 cycles
2,577 LLC-loads

0.102416870 seconds time elapsed

root@otcpl-adl-s-2:~# ./perf stat -e cpu_atom/cycles/,cpu_atom/LLC-loads/ -vv -- taskset -c 16 ./triad_loop
Control descriptor is not initialized
------------------------------------------------------------
perf_event_attr:
type 6
size 120
config 0xa00000000
sample_type IDENTIFIER
read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
disabled 1
inherit 1
enable_on_exec 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid 29212 cpu -1 group_fd -1 flags 0x8 = 3
------------------------------------------------------------
perf_event_attr:
type 7
size 120
config 0xa00000002
sample_type IDENTIFIER
read_format TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
disabled 1
inherit 1
enable_on_exec 1
exclude_guest 1
------------------------------------------------------------
sys_perf_event_open: pid 29212 cpu -1 group_fd -1 flags 0x8 = 4
cycles: 0: 602052607 201353578 200990459
LLC-loads: 0: 4428 201353578 200990459
cycles: 603140304 201353578 200990459
LLC-loads: 4435 201353578 200990459

Performance counter stats for 'taskset -c 16 ./triad_loop':

603,140,304 cycles (99.82%)
4,435 LLC-loads (99.82%)

0.203948454 seconds time elapsed

Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
tools/perf/util/parse-events.c | 100 ++++++++++++++++++++++++++++++++++++++---
tools/perf/util/parse-events.h | 6 ++-
tools/perf/util/parse-events.y | 21 +++------
3 files changed, 105 insertions(+), 22 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 28d356e..bba7db3 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -489,7 +489,8 @@ static int create_hybrid_cache_event(struct list_head *list, int *idx,
static int add_hybrid_cache(struct list_head *list, int *idx,
struct perf_event_attr *attr, char *name,
struct list_head *config_terms,
- bool *hybrid)
+ bool *hybrid,
+ struct parse_events_state *parse_state)
{
struct perf_pmu *pmu;
int ret;
@@ -497,6 +498,11 @@ static int add_hybrid_cache(struct list_head *list, int *idx,
*hybrid = false;
perf_pmu__for_each_hybrid_pmus(pmu) {
*hybrid = true;
+ if (parse_state->pmu_name &&
+ strcmp(parse_state->pmu_name, pmu->name)) {
+ continue;
+ }
+
ret = create_hybrid_cache_event(list, idx, attr, name,
config_terms, pmu);
if (ret)
@@ -509,7 +515,8 @@ static int add_hybrid_cache(struct list_head *list, int *idx,
int parse_events_add_cache(struct list_head *list, int *idx,
char *type, char *op_result1, char *op_result2,
struct parse_events_error *err,
- struct list_head *head_config)
+ struct list_head *head_config,
+ struct parse_events_state *parse_state)
{
struct perf_event_attr attr;
LIST_HEAD(config_terms);
@@ -582,7 +589,7 @@ int parse_events_add_cache(struct list_head *list, int *idx,
perf_pmu__scan(NULL);

ret = add_hybrid_cache(list, idx, &attr, config_name ? : name,
- &config_terms, &hybrid);
+ &config_terms, &hybrid, parse_state);
if (hybrid)
return ret;

@@ -1512,6 +1519,11 @@ static int add_hybrid_numeric(struct parse_events_state *parse_state,
*hybrid = false;
perf_pmu__for_each_hybrid_pmus(pmu) {
*hybrid = true;
+ if (parse_state->pmu_name &&
+ strcmp(parse_state->pmu_name, pmu->name)) {
+ continue;
+ }
+
ret = create_hybrid_hw_event(parse_state, list, attr, pmu);
if (ret)
return ret;
@@ -1578,6 +1590,10 @@ static bool config_term_percore(struct list_head *config_terms)
return false;
}

+static int parse_events_with_hybrid_pmu(struct parse_events_state *parse_state,
+ const char *str, char *name, bool *found,
+ struct list_head *list);
+
int parse_events_add_pmu(struct parse_events_state *parse_state,
struct list_head *list, char *name,
struct list_head *head_config,
@@ -1589,7 +1605,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
struct perf_pmu *pmu;
struct evsel *evsel;
struct parse_events_error *err = parse_state->error;
- bool use_uncore_alias;
+ bool use_uncore_alias, found;
LIST_HEAD(config_terms);

if (verbose > 1) {
@@ -1605,6 +1621,22 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
fprintf(stderr, "' that may result in non-fatal errors\n");
}

+ if (head_config && perf_pmu__is_hybrid(name)) {
+ struct parse_events_term *term;
+ int ret;
+
+ list_for_each_entry(term, head_config, list) {
+ if (!term->config)
+ continue;
+ ret = parse_events_with_hybrid_pmu(parse_state,
+ term->config,
+ name, &found,
+ list);
+ if (found)
+ return ret;
+ }
+ }
+
pmu = parse_state->fake_pmu ?: perf_pmu__find(name);
if (!pmu) {
char *err_str;
@@ -1713,12 +1745,19 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
struct perf_pmu *pmu = NULL;
int ok = 0;

+ if (parse_state->pmu_name) {
+ list = alloc_list();
+ if (!list)
+ return -1;
+ *listp = list;
+ return 0;
+ }
+
*listp = NULL;
/* Add it for all PMUs that support the alias */
- list = malloc(sizeof(struct list_head));
+ list = alloc_list();
if (!list)
return -1;
- INIT_LIST_HEAD(list);
while ((pmu = perf_pmu__scan(pmu)) != NULL) {
struct perf_pmu_alias *alias;

@@ -2284,6 +2323,44 @@ int parse_events_terms(struct list_head *terms, const char *str)
return ret;
}

+static int list_num(struct list_head *list)
+{
+ struct list_head *pos;
+ int n = 0;
+
+ list_for_each(pos, list)
+ n++;
+
+ return n;
+}
+
+static int parse_events_with_hybrid_pmu(struct parse_events_state *parse_state,
+ const char *str, char *pmu_name,
+ bool *found, struct list_head *list)
+{
+ struct parse_events_state ps = {
+ .list = LIST_HEAD_INIT(ps.list),
+ .stoken = PE_START_EVENTS,
+ .pmu_name = pmu_name,
+ .idx = parse_state->idx,
+ };
+ int ret;
+
+ *found = false;
+ ret = parse_events__scanner(str, &ps);
+ perf_pmu__parse_cleanup();
+
+ if (!ret) {
+ if (!list_empty(&ps.list)) {
+ *found = true;
+ list_splice(&ps.list, list);
+ parse_state->idx = list_num(list);
+ }
+ }
+
+ return ret;
+}
+
int __parse_events(struct evlist *evlist, const char *str,
struct parse_events_error *err, struct perf_pmu *fake_pmu)
{
@@ -3309,3 +3386,14 @@ char *parse_events_formats_error_string(char *additional_terms)
fail:
return NULL;
}
+
+struct list_head *alloc_list(void)
+{
+ struct list_head *list = malloc(sizeof(*list));
+
+ if (!list)
+ return NULL;
+
+ INIT_LIST_HEAD(list);
+ return list;
+}
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index b875485..6c91abc 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -138,6 +138,7 @@ struct parse_events_state {
struct list_head *terms;
int stoken;
struct perf_pmu *fake_pmu;
+ char *pmu_name;
};

void parse_events__handle_error(struct parse_events_error *err, int idx,
@@ -188,7 +189,8 @@ int parse_events_add_tool(struct parse_events_state *parse_state,
int parse_events_add_cache(struct list_head *list, int *idx,
char *type, char *op_result1, char *op_result2,
struct parse_events_error *error,
- struct list_head *head_config);
+ struct list_head *head_config,
+ struct parse_events_state *parse_state);
int parse_events_add_breakpoint(struct list_head *list, int *idx,
u64 addr, char *type, u64 len);
int parse_events_add_pmu(struct parse_events_state *parse_state,
@@ -243,6 +245,8 @@ char *parse_events_formats_error_string(char *additional_terms);
void parse_events_print_error(struct parse_events_error *err,
const char *event);

+struct list_head *alloc_list(void);
+
#ifdef HAVE_LIBELF_SUPPORT
/*
* If the probe point starts with '%',
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index d5b6aff..137c7fa 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -26,18 +26,6 @@ do { \
YYABORT; \
} while (0)

-static struct list_head* alloc_list(void)
-{
- struct list_head *list;
-
- list = malloc(sizeof(*list));
- if (!list)
- return NULL;
-
- INIT_LIST_HEAD(list);
- return list;
-}
-
static void free_list_evsel(struct list_head* list_evsel)
{
struct evsel *evsel, *tmp;
@@ -450,7 +438,8 @@ PE_NAME_CACHE_TYPE '-' PE_NAME_CACHE_OP_RESULT '-' PE_NAME_CACHE_OP_RESULT opt_e

list = alloc_list();
ABORT_ON(!list);
- err = parse_events_add_cache(list, &parse_state->idx, $1, $3, $5, error, $6);
+ err = parse_events_add_cache(list, &parse_state->idx, $1, $3, $5, error, $6,
+ parse_state);
parse_events_terms__delete($6);
free($1);
free($3);
@@ -471,7 +460,8 @@ PE_NAME_CACHE_TYPE '-' PE_NAME_CACHE_OP_RESULT opt_event_config

list = alloc_list();
ABORT_ON(!list);
- err = parse_events_add_cache(list, &parse_state->idx, $1, $3, NULL, error, $4);
+ err = parse_events_add_cache(list, &parse_state->idx, $1, $3, NULL, error, $4,
+ parse_state);
parse_events_terms__delete($4);
free($1);
free($3);
@@ -491,7 +481,8 @@ PE_NAME_CACHE_TYPE opt_event_config

list = alloc_list();
ABORT_ON(!list);
- err = parse_events_add_cache(list, &parse_state->idx, $1, NULL, NULL, error, $2);
+ err = parse_events_add_cache(list, &parse_state->idx, $1, NULL, NULL, error, $2,
+ parse_state);
parse_events_terms__delete($2);
free($1);
if (err) {
--
2.7.4