[sysprof] sources/perf: Include the sample identifier in PERF_RECORD_SAMPLE.

[Christian Hergert <chergert src gnome org>]

commit 925dadce826719e1ad1b7c3cde4c04f76872a617
Author: Eric Anholt <eric anholt net>
Date:   Wed May 16 09:37:41 2018 +0100

    sources/perf: Include the sample identifier in PERF_RECORD_SAMPLE.
    
    If we want to start watching other perf events, we need a way to look
    up what perf event we got when a PERF_RECORD_SAMPLE comes in.  The
    sample identifier is what does that.

 lib/sources/sp-perf-counter.h |    1 +
 lib/sources/sp-perf-source.c  |    1 +
 2 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/lib/sources/sp-perf-counter.h b/lib/sources/sp-perf-counter.h
index 213aff3..a473b3d 100644
--- a/lib/sources/sp-perf-counter.h
+++ b/lib/sources/sp-perf-counter.h
@@ -81,6 +81,7 @@ typedef struct
 typedef struct
 {
   struct perf_event_header header;
+  guint64 identifier;
   guint64 ip;
   guint32 pid;
   guint32 tid;
diff --git a/lib/sources/sp-perf-source.c b/lib/sources/sp-perf-source.c
index a7da6cc..b762c24 100644
--- a/lib/sources/sp-perf-source.c
+++ b/lib/sources/sp-perf-source.c
@@ -291,6 +291,7 @@ sp_perf_source_start_pid (SpPerfSource  *self,
 
   attr.sample_type = PERF_SAMPLE_IP
                    | PERF_SAMPLE_TID
+                   | PERF_SAMPLE_IDENTIFIER
                    | PERF_SAMPLE_CALLCHAIN
                    | PERF_SAMPLE_TIME;
   attr.wakeup_events = N_WAKEUP_EVENTS;