perf: Add kernel side syscall events support for breakpoints
Frederic Weisbecker [Mon, 23 Nov 2009 14:42:34 +0000 (15:42 +0100)]
Add the remaining necessary bits to support breakpoints created
through perf syscall.

We don't use the software counter interface as:

- We don't need to check against recursion, this is already done
  in hardware breakpoints arch level.

- We already know the perf event we are dealing with when the
  event is to be committed.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258987355-8751-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/perf_event.c

index 0aafe85..9425c96 100644 (file)
@@ -3831,6 +3831,20 @@ static int perf_swevent_is_counting(struct perf_event *event)
 static int perf_tp_event_match(struct perf_event *event,
                                struct perf_sample_data *data);
 
+static int perf_exclude_event(struct perf_event *event,
+                             struct pt_regs *regs)
+{
+       if (regs) {
+               if (event->attr.exclude_user && user_mode(regs))
+                       return 1;
+
+               if (event->attr.exclude_kernel && !user_mode(regs))
+                       return 1;
+       }
+
+       return 0;
+}
+
 static int perf_swevent_match(struct perf_event *event,
                                enum perf_type_id type,
                                u32 event_id,
@@ -3842,16 +3856,12 @@ static int perf_swevent_match(struct perf_event *event,
 
        if (event->attr.type != type)
                return 0;
+
        if (event->attr.config != event_id)
                return 0;
 
-       if (regs) {
-               if (event->attr.exclude_user && user_mode(regs))
-                       return 0;
-
-               if (event->attr.exclude_kernel && !user_mode(regs))
-                       return 0;
-       }
+       if (perf_exclude_event(event, regs))
+               return 0;
 
        if (event->attr.type == PERF_TYPE_TRACEPOINT &&
            !perf_tp_event_match(event, data))
@@ -4282,9 +4292,15 @@ static const struct pmu *bp_perf_event_init(struct perf_event *bp)
        return &perf_ops_bp;
 }
 
-void perf_bp_event(struct perf_event *bp, void *regs)
+void perf_bp_event(struct perf_event *bp, void *data)
 {
-       /* TODO */
+       struct perf_sample_data sample;
+       struct pt_regs *regs = data;
+
+       sample.addr = bp->attr.bp_addr;
+
+       if (!perf_exclude_event(bp, regs))
+               perf_swevent_add(bp, 1, 1, &sample, regs);
 }
 #else
 static void bp_perf_event_destroy(struct perf_event *event)