perf/x86/ibs: Add IBS interrupt to the dynamic throttle

Interrupt throttling is normally only done against
sysctl_perf_event_sample_rate. This means that if that number is too
high (for whatever reason) you can lock up your machine.

We have, however, a dynamic throttling scheme too, but for that to
work, we need to add a callback to the interrupt handler, IBS did not
have this, so add it.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c
index c43a36d5fd6f..3ea25c3917c0 100644
--- a/arch/x86/events/amd/ibs.c
+++ b/arch/x86/events/amd/ibs.c
@@ -637,6 +637,7 @@ out:
 static int
 perf_ibs_nmi_handler(unsigned int cmd, struct pt_regs *regs)
 {
+	u64 stamp = sched_clock();
 	int handled = 0;
 
 	handled += perf_ibs_handle_irq(&perf_ibs_fetch, regs);
@@ -645,6 +646,8 @@ perf_ibs_nmi_handler(unsigned int cmd, struct pt_regs *regs)
 	if (handled)
 		inc_irq_stat(apic_perf_irqs);
 
+	perf_sample_event_took(sched_clock() - stamp);
+
 	return handled;
 }
 NOKPROBE_SYMBOL(perf_ibs_nmi_handler);