linux-kernel - [PATCH V7 04/14] perf/x86/intel: Move BTS index to 47

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Date:   Thu, 23 Jul 2020 10:11:07 -0700
From:   kan.liang@...ux.intel.com
To:     peterz@...radead.org, acme@...hat.com, mingo@...nel.org,
        linux-kernel@...r.kernel.org
Cc:     jolsa@...nel.org, eranian@...gle.com,
        alexander.shishkin@...ux.intel.com, ak@...ux.intel.com,
        like.xu@...ux.intel.com, Kan Liang <kan.liang@...ux.intel.com>
Subject: [PATCH V7 04/14] perf/x86/intel: Move BTS index to 47

From: Kan Liang <kan.liang@...ux.intel.com>

The bit 48 in the PERF_GLOBAL_STATUS is used to indicate the overflow
status of the PERF_METRICS counters.

Move the BTS index to the bit 47.

Signed-off-by: Kan Liang <kan.liang@...ux.intel.com>
---
 arch/x86/include/asm/perf_event.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index fe8110a8c75b..58419e50ff98 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -238,11 +238,11 @@ struct x86_pmu_capability {
 /*
  * We model BTS tracing as another fixed-mode PMC.
  *
- * We choose a value in the middle of the fixed event range, since lower
+ * We choose the value 47 for the fixed index of BTS, since lower
  * values are used by actual fixed events and higher values are used
  * to indicate other overflow conditions in the PERF_GLOBAL_STATUS msr.
  */
-#define INTEL_PMC_IDX_FIXED_BTS			(INTEL_PMC_IDX_FIXED + 16)
+#define INTEL_PMC_IDX_FIXED_BTS			(INTEL_PMC_IDX_FIXED + 15)
 
 #define GLOBAL_STATUS_COND_CHG			BIT_ULL(63)
 #define GLOBAL_STATUS_BUFFER_OVF_BIT		62
-- 
2.17.1