[tip:perf/core] perf/x86-ibs: Catch spurious interrupts after stopping IBS

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Commit-ID:  fc5fb2b5e1874e5894e2ac503bfb744220db89a1
Gitweb:     http://git.kernel.org/tip/fc5fb2b5e1874e5894e2ac503bfb744220db89a1
Author:     Robert Richter <robert.richter@xxxxxxx>
AuthorDate: Mon, 2 Apr 2012 20:19:17 +0200
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 9 May 2012 15:23:16 +0200

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 <robert.richter@xxxxxxx>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1333390758-10893-12-git-send-email-robert.richter@xxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/x86/kernel/cpu/perf_event_amd_ibs.c |   12 +++++++-----
 1 files 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;
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Stable Commits]     [Linux Stable Kernel]     [Linux Kernel]     [Linux USB Devel]     [Linux Video &Media]     [Linux Audio Users]     [Yosemite News]     [Linux SCSI]

  Powered by Linux