From fc5fb2b5e1874e5894e2ac503bfb744220db89a1 Mon Sep 17 00:00:00 2001 From: Robert Richter Date: Mon, 2 Apr 2012 20:19:17 +0200 Subject: [PATCH] perf/x86-ibs: Catch spurious interrupts after stopping IBS After disabling IBS there could be still incomming NMIs with samples that even have the valid bit cleared. Mark all this NMIs as handled to avoid spurious interrupt messages. Signed-off-by: Robert Richter Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1333390758-10893-12-git-send-email-robert.richter@amd.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event_amd_ibs.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_amd_ibs.c b/arch/x86/kernel/cpu/perf_event_amd_ibs.c index b14e711..5a9f95b 100644 --- a/arch/x86/kernel/cpu/perf_event_amd_ibs.c +++ b/arch/x86/kernel/cpu/perf_event_amd_ibs.c @@ -473,11 +473,13 @@ static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs) u64 *buf, *config, period; if (!test_bit(IBS_STARTED, pcpu->state)) { - /* Catch spurious interrupts after stopping IBS: */ - if (!test_and_clear_bit(IBS_STOPPING, pcpu->state)) - return 0; - rdmsrl(perf_ibs->msr, *ibs_data.regs); - return (*ibs_data.regs & perf_ibs->valid_mask) ? 1 : 0; + /* + * Catch spurious interrupts after stopping IBS: After + * disabling IBS there could be still incomming NMIs + * with samples that even have the valid bit cleared. + * Mark all this NMIs as handled. + */ + return test_and_clear_bit(IBS_STOPPING, pcpu->state) ? 1 : 0; } msr = hwc->config_base; -- 2.7.4