perf: Add context field to perf_event
The perf_event overflow handler does not receive any caller-derived
argument, so many callers need to resort to looking up the perf_event
in their local data structure. This is ugly and doesn't scale if a
single callback services many perf_events.
Fix by adding a context parameter to perf_event_create_kernel_counter()
(and derived hardware breakpoints APIs) and storing it in the perf_event.
The field can be accessed from the callback as event->overflow_handler_context.
All callers are updated.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1309362157-6596-2-git-send-email-avi@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 0c9b105..5c19961 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -479,7 +479,8 @@
attr.bp_type = type;
attr.disabled = 1;
- return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, tsk);
+ return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL,
+ tsk);
}
static int ptrace_gethbpregs(struct task_struct *tsk, long num,