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>
This commit is contained in:
Avi Kivity
2011-06-29 18:42:35 +03:00
committed by Ingo Molnar
parent 89d6c0b5bd
commit 4dc0da8696
12 changed files with 44 additions and 20 deletions

View File

@ -638,7 +638,7 @@ void kgdb_arch_late(void)
for (i = 0; i < HBP_NUM; i++) {
if (breakinfo[i].pev)
continue;
breakinfo[i].pev = register_wide_hw_breakpoint(&attr, NULL);
breakinfo[i].pev = register_wide_hw_breakpoint(&attr, NULL, NULL);
if (IS_ERR((void * __force)breakinfo[i].pev)) {
printk(KERN_ERR "kgdb: Could not allocate hw"
"breakpoints\nDisabling the kernel debugger\n");