1 files changed, 118 insertions, 15 deletions

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index cd7fbda5e2a5..d14a4585bcaf 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -48,6 +48,9 @@
 
 /* If there is no space to write, returns -E2BIG. */
 static int e_snprintf(char *str, size_t size, const char *format, ...)
+        __attribute__((format(printf, 3, 4)));
+
+static int e_snprintf(char *str, size_t size, const char *format, ...)
 {
         int ret;
         va_list ap;
@@ -258,7 +261,7 @@ int synthesize_perf_probe_event(struct probe_point *pp)
                 ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s", pp->function,
                                  offs, pp->retprobe ? "%return" : "", line);
         else
-                ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s", pp->file, line);
+                ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", pp->file, line);
         if (ret <= 0)
                 goto error;
         len = ret;
@@ -373,14 +376,32 @@ static void clear_probe_point(struct probe_point *pp)
                 free(pp->args);
         for (i = 0; i < pp->found; i++)
                 free(pp->probes[i]);
-        memset(pp, 0, sizeof(pp));
+        memset(pp, 0, sizeof(*pp));
+}
+
+/* Show an event */
+static void show_perf_probe_event(const char *group, const char *event,
+                                  const char *place, struct probe_point *pp)
+{
+        int i;
+        char buf[128];
+
+        e_snprintf(buf, 128, "%s:%s", group, event);
+        printf("  %-40s (on %s", buf, place);
+
+        if (pp->nr_args > 0) {
+                printf(" with");
+                for (i = 0; i < pp->nr_args; i++)
+                        printf(" %s", pp->args[i]);
+        }
+        printf(")\n");
 }
 
 /* List up current perf-probe events */
 void show_perf_probe_events(void)
 {
         unsigned int i;
-        int fd;
+        int fd, nr;
         char *group, *event;
         struct probe_point pp;
         struct strlist *rawlist;
@@ -393,8 +414,13 @@ void show_perf_probe_events(void)
         for (i = 0; i < strlist__nr_entries(rawlist); i++) {
                 ent = strlist__entry(rawlist, i);
                 parse_trace_kprobe_event(ent->s, &group, &event, &pp);
+                /* Synthesize only event probe point */
+                nr = pp.nr_args;
+                pp.nr_args = 0;
                 synthesize_perf_probe_event(&pp);
-                printf("[%s:%s]\t%s\n", group, event, pp.probes[0]);
+                pp.nr_args = nr;
+                /* Show an event */
+                show_perf_probe_event(group, event, pp.probes[0], &pp);
                 free(group);
                 free(event);
                 clear_probe_point(&pp);
@@ -404,21 +430,28 @@ void show_perf_probe_events(void)
 }
 
 /* Get current perf-probe event names */
-static struct strlist *get_perf_event_names(int fd)
+static struct strlist *get_perf_event_names(int fd, bool include_group)
 {
         unsigned int i;
         char *group, *event;
+        char buf[128];
         struct strlist *sl, *rawlist;
         struct str_node *ent;
 
         rawlist = get_trace_kprobe_event_rawlist(fd);
 
-        sl = strlist__new(false, NULL);
+        sl = strlist__new(true, NULL);
         for (i = 0; i < strlist__nr_entries(rawlist); i++) {
                 ent = strlist__entry(rawlist, i);
                 parse_trace_kprobe_event(ent->s, &group, &event, NULL);
-                strlist__add(sl, event);
+                if (include_group) {
+                        if (e_snprintf(buf, 128, "%s:%s", group, event) < 0)
+                                die("Failed to copy group:event name.");
+                        strlist__add(sl, buf);
+                } else
+                        strlist__add(sl, event);
                 free(group);
+                free(event);
         }
 
         strlist__delete(rawlist);
@@ -426,24 +459,30 @@ static struct strlist *get_perf_event_names(int fd)
         return sl;
 }
 
-static int write_trace_kprobe_event(int fd, const char *buf)
+static void write_trace_kprobe_event(int fd, const char *buf)
 {
         int ret;
 
+        pr_debug("Writing event: %s\n", buf);
         ret = write(fd, buf, strlen(buf));
         if (ret <= 0)
-                die("Failed to create event.");
-        else
-                printf("Added new event: %s\n", buf);
-
-        return ret;
+                die("Failed to write event: %s", strerror(errno));
 }
 
 static void get_new_event_name(char *buf, size_t len, const char *base,
                                struct strlist *namelist)
 {
         int i, ret;
-        for (i = 0; i < MAX_EVENT_INDEX; i++) {
+
+        /* Try no suffix */
+        ret = e_snprintf(buf, len, "%s", base);
+        if (ret < 0)
+                die("snprintf() failed: %s", strerror(-ret));
+        if (!strlist__has_entry(namelist, buf))
+                return;
+
+        /* Try to add suffix */
+        for (i = 1; i < MAX_EVENT_INDEX; i++) {
                 ret = e_snprintf(buf, len, "%s_%d", base, i);
                 if (ret < 0)
                         die("snprintf() failed: %s", strerror(-ret));
@@ -464,7 +503,7 @@ void add_trace_kprobe_events(struct probe_point *probes, int nr_probes)
 
         fd = open_kprobe_events(O_RDWR, O_APPEND);
         /* Get current event names */
-        namelist = get_perf_event_names(fd);
+        namelist = get_perf_event_names(fd, false);
 
         for (j = 0; j < nr_probes; j++) {
                 pp = probes + j;
@@ -476,9 +515,73 @@ void add_trace_kprobe_events(struct probe_point *probes, int nr_probes)
                                  PERFPROBE_GROUP, event,
                                  pp->probes[i]);
                         write_trace_kprobe_event(fd, buf);
+                        printf("Added new event:\n");
+                        /* Get the first parameter (probe-point) */
+                        sscanf(pp->probes[i], "%s", buf);
+                        show_perf_probe_event(PERFPROBE_GROUP, event,
+                                              buf, pp);
                         /* Add added event name to namelist */
                         strlist__add(namelist, event);
                 }
         }
+        /* Show how to use the event. */
+        printf("\nYou can now use it on all perf tools, such as:\n\n");
+        printf("\tperf record -e %s:%s -a sleep 1\n\n", PERFPROBE_GROUP, event);
+
+        strlist__delete(namelist);
+        close(fd);
+}
+
+static void del_trace_kprobe_event(int fd, const char *group,
+                                   const char *event, struct strlist *namelist)
+{
+        char buf[128];
+
+        if (e_snprintf(buf, 128, "%s:%s", group, event) < 0)
+                die("Failed to copy event.");
+        if (!strlist__has_entry(namelist, buf)) {
+                pr_warning("Warning: event \"%s\" is not found.\n", buf);
+                return;
+        }
+        /* Convert from perf-probe event to trace-kprobe event */
+        if (e_snprintf(buf, 128, "-:%s/%s", group, event) < 0)
+                die("Failed to copy event.");
+
+        write_trace_kprobe_event(fd, buf);
+        printf("Remove event: %s:%s\n", group, event);
+}
+
+void del_trace_kprobe_events(struct strlist *dellist)
+{
+        int fd;
+        unsigned int i;
+        const char *group, *event;
+        char *p, *str;
+        struct str_node *ent;
+        struct strlist *namelist;
+
+        fd = open_kprobe_events(O_RDWR, O_APPEND);
+        /* Get current event names */
+        namelist = get_perf_event_names(fd, true);
+
+        for (i = 0; i < strlist__nr_entries(dellist); i++) {
+                ent = strlist__entry(dellist, i);
+                str = strdup(ent->s);
+                if (!str)
+                        die("Failed to copy event.");
+                p = strchr(str, ':');
+                if (p) {
+                        group = str;
+                        *p = '\0';
+                        event = p + 1;
+                } else {
+                        group = PERFPROBE_GROUP;
+                        event = str;
+                }
+                del_trace_kprobe_event(fd, group, event, namelist);
+                free(str);
+        }
+        strlist__delete(namelist);
         close(fd);
 }
+