[PATCH v2 2/5] perf probe: Attach trace_probe_event with perf_probe_event

[Namhyung Kim <namhyung@kernel.org>]

From: Wang Nan <wangnan0@huawei.com>

This patch drops struct __event_package structure.  Instead, it adds
trace_probe_event into 'struct perf_probe_event'.

trace_probe_event information gives further patches a chance to access
actual probe points and actual arguments.  Using them, perf probe can
get whole list of added probes and print them at once.

Other users like upcoming bpf_loader will be able to attach one bpf
program to different probing points of an inline functions (which has
multiple probing points) and glob functions.  Moreover, by reading
arguments information, bpf code for reading those arguments can be
generated.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
[namhyung: extract necessary part from the existing patch]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/probe-event.c | 57 +++++++++++++------------------------------
 tools/perf/util/probe-event.h |  5 ++++
 2 files changed, 22 insertions(+), 40 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 2c762f41e7a5..0d3a051b9202 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2759,59 +2759,39 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
 	return find_probe_trace_events_from_map(pev, tevs);
 }
 
-struct __event_package {
-	struct perf_probe_event		*pev;
-	struct probe_trace_event	*tevs;
-	int				ntevs;
-};
-
-static int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs,
-				     struct __event_package **ppkgs)
+int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 {
 	int i, ret;
-	struct __event_package *pkgs;
-
-	ret = 0;
-	pkgs = zalloc(sizeof(struct __event_package) * npevs);
-
-	if (pkgs == NULL)
-		return -ENOMEM;
 
 	ret = init_symbol_maps(pevs->uprobes);
-	if (ret < 0) {
-		free(pkgs);
+	if (ret < 0)
 		return ret;
-	}
 
 	/* Loop 1: convert all events */
 	for (i = 0; i < npevs; i++) {
-		pkgs[i].pev = &pevs[i];
 		/* Init kprobe blacklist if needed */
-		if (!pkgs[i].pev->uprobes)
+		if (!pevs[i].uprobes)
 			kprobe_blacklist__init();
 		/* Convert with or without debuginfo */
-		ret  = convert_to_probe_trace_events(pkgs[i].pev,
-						     &pkgs[i].tevs);
+		ret  = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs);
 		if (ret < 0)
 			return ret;
-		pkgs[i].ntevs = ret;
+		pevs[i].ntevs = ret;
 	}
 	/* This just release blacklist only if allocated */
 	kprobe_blacklist__release();
 
-	*ppkgs = pkgs;
-
 	return 0;
 }
 
-static int apply_perf_probe_events(struct __event_package *pkgs, int npevs)
+int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 {
 	int i, ret = 0;
 
 	/* Loop 2: add all events */
 	for (i = 0; i < npevs; i++) {
-		ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs,
-					       pkgs[i].ntevs,
+		ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs,
+					       pevs[i].ntevs,
 					       probe_conf.force_add);
 		if (ret < 0)
 			break;
@@ -2819,33 +2799,30 @@ static int apply_perf_probe_events(struct __event_package *pkgs, int npevs)
 	return ret;
 }
 
-static void cleanup_perf_probe_events(struct __event_package *pkgs, int npevs)
+void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 {
 	int i, j;
 
-	if (pkgs == NULL)
-		return;
-
 	/* Loop 3: cleanup and free trace events  */
 	for (i = 0; i < npevs; i++) {
-		for (j = 0; j < pkgs[i].ntevs; j++)
-			clear_probe_trace_event(&pkgs[i].tevs[j]);
-		zfree(&pkgs[i].tevs);
+		for (j = 0; j < pevs[i].ntevs; j++)
+			clear_probe_trace_event(&pevs[i].tevs[j]);
+		zfree(&pevs[i].tevs);
+		pevs[i].ntevs = 0;
 	}
-	free(pkgs);
+
 	exit_symbol_maps();
 }
 
 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 {
 	int ret;
-	struct __event_package *pkgs = NULL;
 
-	ret = convert_perf_probe_events(pevs, npevs, &pkgs);
+	ret = convert_perf_probe_events(pevs, npevs);
 	if (ret == 0)
-		ret = apply_perf_probe_events(pkgs, npevs);
+		ret = apply_perf_probe_events(pevs, npevs);
 
-	cleanup_perf_probe_events(pkgs, npevs);
+	cleanup_perf_probe_events(pevs, npevs);
 
 	return ret;
 }
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 6e7ec68a4aa8..70c327bd61de 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -87,6 +87,8 @@ struct perf_probe_event {
 	bool			uprobes;	/* Uprobe event flag */
 	char			*target;	/* Target binary */
 	struct perf_probe_arg	*args;	/* Arguments */
+	struct probe_trace_event *tevs;
+	int			ntevs;
 };
 
 /* Line range */
@@ -138,6 +140,9 @@ extern void line_range__clear(struct line_range *lr);
 extern int line_range__init(struct line_range *lr);
 
 extern int add_perf_probe_events(struct perf_probe_event *pevs, int npevs);
+extern int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs);
+extern int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs);
+extern void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs);
 extern int del_perf_probe_events(struct strfilter *filter);
 extern int show_perf_probe_events(struct strfilter *filter);
 extern int show_line_range(struct line_range *lr, const char *module,
-- 
2.5.0