[PATCH v3 4/4] perf tools: Enable event_config terms to tracepoint events

From: He Kuang
Date: Sun Sep 27 2015 - 23:54:03 EST


This patch enable config terms for tracepoint perf events. Valid terms
for tracepoint events are call-graph and stack-size, so we can use
different callgraph settings for each event and eliminate unnecessary
overhead.

Here is an example for using different call-graph config for each
tracepoint.

$ perf record -e syscalls:sys_enter_write/call-graph=fp/
-e syscalls:sys_exit_write/call-graph=no/
dd if=/dev/zero of=test bs=4k count=10

$ perf report --stdio

#
# Total Lost Samples: 0
#
# Samples: 13 of event 'syscalls:sys_enter_write'
# Event count (approx.): 13
#
# Children Self Command Shared Object Symbol
# ........ ........ ....... .................. ......................
#
76.92% 76.92% dd libpthread-2.20.so [.] __write_nocancel
|
---__write_nocancel

23.08% 23.08% dd libc-2.20.so [.] write
|
---write
|
|--33.33%-- 0x2031342820736574
|
|--33.33%-- 0xa6e69207364726f
|
--33.33%-- 0x34202c7320393039
...

# Samples: 13 of event 'syscalls:sys_exit_write'
# Event count (approx.): 13
#
# Children Self Command Shared Object Symbol
# ........ ........ ....... .................. ......................
#
76.92% 76.92% dd libpthread-2.20.so [.] __write_nocancel
23.08% 23.08% dd libc-2.20.so [.] write
7.69% 0.00% dd [unknown] [.] 0x0a6e69207364726f
7.69% 0.00% dd [unknown] [.] 0x2031342820736574
7.69% 0.00% dd [unknown] [.] 0x34202c7320393039

Signed-off-by: He Kuang <hekuang@xxxxxxxxxx>
---

Changes v2-v3:
- Join improper wrap line.

---
tools/perf/util/parse-events.c | 84 +++++++++++++++++++++++++++++++++---------
tools/perf/util/parse-events.h | 3 +-
tools/perf/util/parse-events.y | 26 +++++++++++--
3 files changed, 90 insertions(+), 23 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index ea64ec07..5ffb356 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -27,6 +27,8 @@
extern int parse_events_debug;
#endif
int parse_events_parse(void *data, void *scanner);
+static int get_config_terms(struct list_head *head_config,
+ struct list_head *head_terms __maybe_unused);

static struct perf_pmu_event_symbol *perf_pmu_events_list;
/*
@@ -416,7 +418,8 @@ static void tracepoint_error(struct parse_events_error *error, int err,

static int add_tracepoint(struct list_head *list, int *idx,
char *sys_name, char *evt_name,
- struct parse_events_error *error __maybe_unused)
+ struct parse_events_error *error __maybe_unused,
+ struct list_head *head_config)
{
struct perf_evsel *evsel;

@@ -426,13 +429,22 @@ static int add_tracepoint(struct list_head *list, int *idx,
return PTR_ERR(evsel);
}

+ if (head_config) {
+ LIST_HEAD(config_terms);
+
+ if (get_config_terms(head_config, &config_terms))
+ return -ENOMEM;
+ list_splice(&config_terms, &evsel->config_terms);
+ }
+
list_add_tail(&evsel->node, list);
return 0;
}

static int add_tracepoint_multi_event(struct list_head *list, int *idx,
char *sys_name, char *evt_name,
- struct parse_events_error *error)
+ struct parse_events_error *error,
+ struct list_head *head_config)
{
char evt_path[MAXPATHLEN];
struct dirent *evt_ent;
@@ -456,7 +468,8 @@ static int add_tracepoint_multi_event(struct list_head *list, int *idx,
if (!strglobmatch(evt_ent->d_name, evt_name))
continue;

- ret = add_tracepoint(list, idx, sys_name, evt_ent->d_name, error);
+ ret = add_tracepoint(list, idx, sys_name, evt_ent->d_name,
+ error, head_config);
}

closedir(evt_dir);
@@ -465,16 +478,20 @@ static int add_tracepoint_multi_event(struct list_head *list, int *idx,

static int add_tracepoint_event(struct list_head *list, int *idx,
char *sys_name, char *evt_name,
- struct parse_events_error *error)
+ struct parse_events_error *error,
+ struct list_head *head_config)
{
return strpbrk(evt_name, "*?") ?
- add_tracepoint_multi_event(list, idx, sys_name, evt_name, error) :
- add_tracepoint(list, idx, sys_name, evt_name, error);
+ add_tracepoint_multi_event(list, idx, sys_name, evt_name,
+ error, head_config) :
+ add_tracepoint(list, idx, sys_name, evt_name,
+ error, head_config);
}

static int add_tracepoint_multi_sys(struct list_head *list, int *idx,
char *sys_name, char *evt_name,
- struct parse_events_error *error)
+ struct parse_events_error *error,
+ struct list_head *head_config)
{
struct dirent *events_ent;
DIR *events_dir;
@@ -498,23 +515,13 @@ static int add_tracepoint_multi_sys(struct list_head *list, int *idx,
continue;

ret = add_tracepoint_event(list, idx, events_ent->d_name,
- evt_name, error);
+ evt_name, error, head_config);
}

closedir(events_dir);
return ret;
}

-int parse_events_add_tracepoint(struct list_head *list, int *idx,
- char *sys, char *event,
- struct parse_events_error *error)
-{
- if (strpbrk(sys, "*?"))
- return add_tracepoint_multi_sys(list, idx, sys, event, error);
- else
- return add_tracepoint_event(list, idx, sys, event, error);
-}
-
static int
parse_breakpoint_type(const char *type, struct perf_event_attr *attr)
{
@@ -680,6 +687,26 @@ static int config_term_pmu(struct perf_event_attr *attr,
return config_term_common(attr, term, err);
}

+static int config_term_tracepoint(struct perf_event_attr *attr,
+ struct parse_events_term *term,
+ struct parse_events_error *err)
+{
+ switch (term->type_term) {
+ case PARSE_EVENTS__TERM_TYPE_CALLGRAPH:
+ case PARSE_EVENTS__TERM_TYPE_STACKSIZE:
+ return config_term_common(attr, term, err);
+ default:
+ if (err) {
+ err->idx = term->err_term;
+ err->str = strdup("unknown term");
+ err->help = strdup("valid terms: call-graph,stack-size\n");
+ }
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static int config_attr(struct perf_event_attr *attr,
struct list_head *head,
struct parse_events_error *err,
@@ -738,6 +765,27 @@ do { \
return 0;
}

+int parse_events_add_tracepoint(struct list_head *list, int *idx,
+ char *sys, char *event,
+ struct parse_events_error *error,
+ struct list_head *head_config)
+{
+ if (head_config) {
+ struct perf_event_attr attr;
+
+ if (config_attr(&attr, head_config, error,
+ config_term_tracepoint))
+ return -EINVAL;
+ }
+
+ if (strpbrk(sys, "*?"))
+ return add_tracepoint_multi_sys(list, idx, sys, event,
+ error, head_config);
+ else
+ return add_tracepoint_event(list, idx, sys, event,
+ error, head_config);
+}
+
int parse_events_add_numeric(struct parse_events_evlist *data,
struct list_head *list,
u32 type, u64 config,
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index c7b904a..f13d3cc 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -119,7 +119,8 @@ int parse_events__modifier_group(struct list_head *list, char *event_mod);
int parse_events_name(struct list_head *list, char *name);
int parse_events_add_tracepoint(struct list_head *list, int *idx,
char *sys, char *event,
- struct parse_events_error *error);
+ struct parse_events_error *error,
+ struct list_head *head_config);
int parse_events_add_numeric(struct parse_events_evlist *data,
struct list_head *list,
u32 type, u64 config,
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index 1c598c2..ae6af26 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -380,12 +380,30 @@ tracepoint_name
struct list_head *list;

ALLOC_LIST(list);
+ if (error)
+ error->idx = @1.first_column;
+
if (parse_events_add_tracepoint(list, &data->idx, $1.sys, $1.event,
- error)) {
- if (error)
- error->idx = @1.first_column;
+ error, NULL))
return -1;
- }
+
+ $$ = list;
+}
+|
+tracepoint_name '/' event_config '/'
+{
+ struct parse_events_evlist *data = _data;
+ struct parse_events_error *error = data->error;
+ struct list_head *list;
+
+ ALLOC_LIST(list);
+ if (error)
+ error->idx = @1.first_column;
+
+ if (parse_events_add_tracepoint(list, &data->idx, $1.sys, $1.event,
+ error, $3))
+ return -1;
+
$$ = list;
}

--
1.8.5.2

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