perf tools: Enable event_config terms to tracepoint events

This patch enables 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@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1443412336-120050-4-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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_multi_event(list, idx, sys_name, evt_name,
-	       add_tracepoint(list, idx, sys_name, evt_name, error);
+					  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,

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,

tools/perf/util/parse-events.y

@@ -380,12 +380,30 @@ tracepoint_name
 	struct list_head *list;
 
 	ALLOC_LIST(list);
-	if (parse_events_add_tracepoint(list, &data->idx, $1.sys, $1.event,
-					error)) {
 	if (error)
 		error->idx = @1.first_column;
+
+	if (parse_events_add_tracepoint(list, &data->idx, $1.sys, $1.event,
+					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;
 }