perf/x86/amd: Make HW_CACHE_REFERENCES and HW_CACHE_MISSES measure L2

While the Intel PMU monitors the LLC when perf enables the
HW_CACHE_REFERENCES and HW_CACHE_MISSES events, these events monitor
L1 instruction cache fetches (0x0080) and instruction cache misses
(0x0081) on the AMD PMU.

This is extremely confusing when monitoring the same workload across
Intel and AMD machines, since parameters like,

  $ perf stat -e cache-references,cache-misses

measure completely different things.

Instead, make the AMD PMU measure instruction/data cache and TLB fill
requests to the L2 and instruction/data cache and TLB misses in the L2
when HW_CACHE_REFERENCES and HW_CACHE_MISSES are enabled,
respectively. That way the events measure unified caches on both
platforms.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1472044328-21302-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index e07a22bb9308d0d030f0052f2f8195a8fbb48df5..f5f4b3fbbbc2924cbac3fe24d45d949e0997dc8e 100644 (file)
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -119,8 +119,8 @@ static const u64 amd_perfmon_event_map[PERF_COUNT_HW_MAX] =
 {
   [PERF_COUNT_HW_CPU_CYCLES]                   = 0x0076,
   [PERF_COUNT_HW_INSTRUCTIONS]                 = 0x00c0,
-  [PERF_COUNT_HW_CACHE_REFERENCES]             = 0x0080,
-  [PERF_COUNT_HW_CACHE_MISSES]                 = 0x0081,
+  [PERF_COUNT_HW_CACHE_REFERENCES]             = 0x077d,
+  [PERF_COUNT_HW_CACHE_MISSES]                 = 0x077e,
   [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]          = 0x00c2,
   [PERF_COUNT_HW_BRANCH_MISSES]                        = 0x00c3,
   [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]      = 0x00d0, /* "Decoder empty" event */

diff --git a/arch/x86/kvm/pmu_amd.c b/arch/x86/kvm/pmu_amd.c
index 39b91127ef07a48a3cf4313d2d0340088bf8b7c6..cd944435dfbd73583a4b2d532f6f47aae022c84e 100644 (file)
--- a/arch/x86/kvm/pmu_amd.c
+++ b/arch/x86/kvm/pmu_amd.c
@@ -23,8 +23,8 @@
 static struct kvm_event_hw_type_mapping amd_event_mapping[] = {
        [0] = { 0x76, 0x00, PERF_COUNT_HW_CPU_CYCLES },
        [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS },
-       [2] = { 0x80, 0x00, PERF_COUNT_HW_CACHE_REFERENCES },
-       [3] = { 0x81, 0x00, PERF_COUNT_HW_CACHE_MISSES },
+       [2] = { 0x7d, 0x07, PERF_COUNT_HW_CACHE_REFERENCES },
+       [3] = { 0x7e, 0x07, PERF_COUNT_HW_CACHE_MISSES },
        [4] = { 0xc2, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
        [5] = { 0xc3, 0x00, PERF_COUNT_HW_BRANCH_MISSES },
        [6] = { 0xd0, 0x00, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND },