[PATCH v5 6/7] perf/sdt: List events fetched from uprobe_events

[Ravi Bangoria]

List those events which are fetched from uprobe_events as 'event addr@file'
followed by hint on how these events can be deleted with 'perf probe -d'
command.

For example:
  $ sudo cat /sys/kernel/debug/tracing/uprobe_events
    p:sdt_libpthread/mutex_release 
/usr/lib64/libpthread-2.24.so:0x000000000000b126

  $ sudo ./perf record -a -e sdt_libpthread:mutex_release
    Matching event(s) from uprobe_events:
       sdt_libpthread:mutex_release  0xb126@/usr/lib64/libpthread-2.24.so
    Use 'perf probe -d <event>' to delete event(s).

Signed-off-by: Ravi Bangoria <ravi.bango...@linux.vnet.ibm.com>
---
 tools/perf/util/probe-event.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 7bf8783..e150de0 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -3593,6 +3593,24 @@ static void sdt_warn_multi_events(int ctr, struct 
perf_probe_event *pev)
                   ctr, pev->group, pev->event);
 }
 
+static void print_exst_sdt_events(struct probe_trace_event *tev)
+{
+       static bool msg_head;
+
+       if (!msg_head) {
+               pr_info("Matching event(s) from uprobe_events:\n");
+               msg_head = true;
+       }
+
+       pr_info("   %s:%s  0x%" PRIx64 "@%s\n", tev->group,
+               tev->event, tev->point.address, tev->point.module);
+}
+
+static void print_exst_sdt_event_footer(void)
+{
+       pr_info("Use 'perf probe -d <event>' to delete event(s).\n\n");
+}
+
 static int sdt_event_probepoint_exists(struct perf_probe_event *pev,
                                       struct probe_trace_event *tevs,
                                       int ntevs,
@@ -3607,10 +3625,14 @@ static int sdt_event_probepoint_exists(struct 
perf_probe_event *pev,
                        if (ret < 0)
                                return ret;
 
+                       print_exst_sdt_events(&tevs[i]);
                        ctr++;
                }
        }
 
+       if (ctr > 0)
+               print_exst_sdt_event_footer();
+
        if (ctr > 1)
                sdt_warn_multi_events(ctr, pev);
 
@@ -3660,11 +3682,16 @@ static int sdt_merge_events(struct perf_probe_event 
*pev,
 
                                if (!ptrn_used)
                                        shift_sdt_events(pev, i);
+
+                               print_exst_sdt_events(&exst_tevs[j]);
                                ctr++;
                        }
                }
        }
 
+       if (ctr > 0)
+               print_exst_sdt_event_footer();
+
        if (!ptrn_used || ctr == 0) {
                /*
                 * Create probe point for all probe-cached events by
-- 
2.9.3