Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1283431
| Path | csiph.com!au2pb.net!2.us.feeder.erje.net!feeder.erje.net!2.eu.feeder.erje.net!nntpspool01.opticnetworks.net!aioe.org!bofh.it!news.nic.it!robomod |
|---|---|
| From | Stephane Eranian <eranian@google.com> |
| Newsgroups | linux.kernel |
| Subject | [PATCH v3 2/4] perf/x86: fix PEBS issues on Intel Atom/Core2 |
| Date | Thu, 03 Dec 2015 23:40:03 +0100 |
| Message-ID | <qBKHF-2Fu-27@gated-at.bofh.it> (permalink) |
| References | <qBKHE-2Fu-9@gated-at.bofh.it> |
| X-Original-To | linux-kernel@vger.kernel.org |
| Dkim-Signature | v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=3L33WSCgtSBpTSTROL+K349eYaW1viLsDaPNLSxDRu4=; b=NNBxplB56aTHFiqBTlHD7t+Fp9kiZjrDvVmjxIT88ZUPivp0Vg3+ac0HDbWg3cqv7A oeLSks52zU6JJ1568VVz/ezbTNQ5Nu3PXP7aqyUob5zP/N7fGTFg1jj57PWMalopms5U EbNbIS6OR1fnnyKf9yKVRdNe/pnhdOL/FP8NEjbFVdanTbdi+8aESD8JmTZ7qxrXcu0E hDySWw7en5EePWwbrw3k8IooPHJY8Mea8hrY9s4IZb3n7WL9AyXQ1/W820FuVl/iyhaR W7Rpd0R2XcSzVeN2he+JfKSVYeohju0udCnmrrYrs25O7/jWUWe1+TTBM6dfoN8L0RV1 oLog== |
| X-Google-Dkim-Signature | v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=3L33WSCgtSBpTSTROL+K349eYaW1viLsDaPNLSxDRu4=; b=HTYgBWaTlO6Rcq++4YQcLn551Q6YSV+vZlP9+vXkBIHvzCsz/WyHcZX98P4t13slZ8 4m5d1f+IDgd7B2u2aUirmKdnNvc2xS8ziEpVMFX5TbRp4t/9DCdZwkzkGzjsEFqzM4i7 BGqv83HqGWLKdTkzKuzN1i58vUOrz0+fsza17Gx14k3LpWLBFkrSebtxveZRyfBtMEEO aqChiiZRMPyGp6uqOt1pI1OZ+vvWDo4AQj+J/P3YPsr+uxZu1Z58LME0fyYc99nI2jYo m1LVL3cB58u7HdcjlTNaPYXt5i/8tpAbVnCvL42Hl5o8urm/fNXf3NBTR0n157TUc6i7 4uZQ== |
| X-Gm-Message-State | ALoCoQnQsGWRfx9kTaDHSzb2akHMakEJjPdhrBCdBVq0cgyKnLeyxlt+CCPIvQAz+CLJ3YYKmxsG |
| X-Received | by 10.98.69.7 with SMTP id s7mr16469519pfa.28.1449182084974; Thu, 03 Dec 2015 14:34:44 -0800 (PST) |
| X-Mailer | git-send-email 1.9.1 |
| Sender | robomod@news.nic.it |
| List-ID | <linux-kernel.vger.kernel.org> |
| X-Mailing-List | linux-kernel@vger.kernel.org |
| Approved | robomod@news.nic.it |
| Lines | 48 |
| Organization | linux.* mail to news gateway |
| X-Original-Cc | acme@redhat.com, peterz@infradead.org, mingo@elte.hu, ak@linux.intel.com, kan.liang@intel.com |
| X-Original-Date | Thu, 3 Dec 2015 23:33:18 +0100 |
| X-Original-Message-ID | <1449182000-31524-3-git-send-email-eranian@google.com> |
| X-Original-References | <1449182000-31524-1-git-send-email-eranian@google.com> |
| X-Original-Sender | linux-kernel-owner@vger.kernel.org |
| Xref | csiph.com linux.kernel:1283431 |
Show key headers only | View raw
This patch fixes broken PEBS support on Intel Atom and Core2
due to wrong pointer arithmetic in intel_pmu_drain_pebs_core().
The get_next_pebs_record_by_bit() was called on PEBS format fmt0
which does not use the pebs_record_nhm layout.
Fixes: 21509084f ("perf/x86/intel: Handle multiple records in the PEBS buffer")
Signed-off-by: Stephane Eranian <eranian@google.com>
---
arch/x86/kernel/cpu/perf_event_intel_ds.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 5db1c77..dae5f93 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -1101,6 +1101,13 @@ get_next_pebs_record_by_bit(void *base, void *top, int bit)
void *at;
u64 pebs_status;
+ /*
+ * fmt0 does not have a status bitfield (does not use
+ * perf_record_nhm format)
+ */
+ if (x86_pmu.intel_cap.pebs_format < 1)
+ return base;
+
if (base == NULL)
return NULL;
@@ -1186,7 +1193,7 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
if (!event->attr.precise_ip)
return;
- n = (top - at) / x86_pmu.pebs_record_size;
+ n = top - at;
if (n <= 0)
return;
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread
[PATCH v3 0/2] perf/x86: fixes and improvements for Intel Atom PEBS/LBR support Stephane Eranian <eranian@google.com> - 2015-12-03 23:40 +0100 [PATCH v3 1/4] perf/x86: fix LBR issues on Intel Atom Stephane Eranian <eranian@google.com> - 2015-12-03 23:40 +0100 [PATCH v3 2/4] perf/x86: fix PEBS issues on Intel Atom/Core2 Stephane Eranian <eranian@google.com> - 2015-12-03 23:40 +0100
csiph-web