[PATCH 4.9 047/117] perf/x86/amd/ibs: Fix raw sample data accumulation

[Greg Kroah-Hartman]

From: Kim Phillips <kim.phillips@xxxxxxx>

commit 36e1be8ada994d509538b3b1d0af8b63c351e729 upstream.

Neither IbsBrTarget nor OPDATA4 are populated in IBS Fetch mode.
Don't accumulate them into raw sample user data in that case.

Also, in Fetch mode, add saving the IBS Fetch Control Extended MSR.

Technically, there is an ABI change here with respect to the IBS raw
sample data format, but I don't see any perf driver version information
being included in perf.data file headers, but, existing users can detect
whether the size of the sample record has reduced by 8 bytes to
determine whether the IBS driver has this fix.

Fixes: 904cb3677f3a ("perf/x86/amd/ibs: Update IBS MSRs and feature definitions")
Reported-by: Stephane Eranian <stephane.eranian@xxxxxxxxxx>
Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20200908214740.18097-6-kim.phillips@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/events/amd/ibs.c        |   26 ++++++++++++++++----------
 arch/x86/include/asm/msr-index.h |    1 +
 2 files changed, 17 insertions(+), 10 deletions(-)

--- a/arch/x86/events/amd/ibs.c
+++ b/arch/x86/events/amd/ibs.c
@@ -646,18 +646,24 @@ fail:
 				       perf_ibs->offset_max,
 				       offset + 1);
 	} while (offset < offset_max);
+	/*
+	 * Read IbsBrTarget, IbsOpData4, and IbsExtdCtl separately
+	 * depending on their availability.
+	 * Can't add to offset_max as they are staggered
+	 */
 	if (event->attr.sample_type & PERF_SAMPLE_RAW) {
-		/*
-		 * Read IbsBrTarget and IbsOpData4 separately
-		 * depending on their availability.
-		 * Can't add to offset_max as they are staggered
-		 */
-		if (ibs_caps & IBS_CAPS_BRNTRGT) {
-			rdmsrl(MSR_AMD64_IBSBRTARGET, *buf++);
-			size++;
+		if (perf_ibs == &perf_ibs_op) {
+			if (ibs_caps & IBS_CAPS_BRNTRGT) {
+				rdmsrl(MSR_AMD64_IBSBRTARGET, *buf++);
+				size++;
+			}
+			if (ibs_caps & IBS_CAPS_OPDATA4) {
+				rdmsrl(MSR_AMD64_IBSOPDATA4, *buf++);
+				size++;
+			}
 		}
-		if (ibs_caps & IBS_CAPS_OPDATA4) {
-			rdmsrl(MSR_AMD64_IBSOPDATA4, *buf++);
+		if (perf_ibs == &perf_ibs_fetch && (ibs_caps & IBS_CAPS_FETCHCTLEXTD)) {
+			rdmsrl(MSR_AMD64_ICIBSEXTDCTL, *buf++);
 			size++;
 		}
 	}
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -356,6 +356,7 @@
 #define MSR_AMD64_IBSOP_REG_MASK	((1UL<<MSR_AMD64_IBSOP_REG_COUNT)-1)
 #define MSR_AMD64_IBSCTL		0xc001103a
 #define MSR_AMD64_IBSBRTARGET		0xc001103b
+#define MSR_AMD64_ICIBSEXTDCTL		0xc001103c
 #define MSR_AMD64_IBSOPDATA4		0xc001103d
 #define MSR_AMD64_IBS_REG_COUNT_MAX	8 /* includes MSR_AMD64_IBSBRTARGET */