perf: Add kernel side syscall events support for breakpoints

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>

1 files changed, 25 insertions, 9 deletions

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 0aafe85362fd..9425c9600c89 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -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)