hw-breakpoints: Use overflow handler instead of the event callback
struct perf_event::event callback was called when a breakpoint
triggers. But this is a rather opaque callback, pretty
tied-only to the breakpoint API and not really integrated into perf
as it triggers even when we don't overflow.
We prefer to use overflow_handler() as it fits into the perf events
rules, being called only when we overflow.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index d42f65a..05d5fec 100644
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -362,8 +362,7 @@
return ret;
}
- if (bp->callback)
- ret = arch_store_info(bp);
+ ret = arch_store_info(bp);
if (ret < 0)
return ret;
@@ -519,7 +518,7 @@
break;
}
- (bp->callback)(bp, args->regs);
+ perf_bp_event(bp, args->regs);
rcu_read_unlock();
}