The following commit has been merged into the perf/urgent branch of tip:
Commit-ID: 2a3da5fe10731ca6ccb396b29be612faee76fb69
Gitweb: https://git.kernel.org/tip/2a3da5fe10731ca6ccb396b29be612faee76fb69
Author: Sandipan Das <[email protected]>
AuthorDate: Mon, 25 Mar 2024 13:17:53 +05:30
Committer: Ingo Molnar <[email protected]>
CommitterDate: Mon, 25 Mar 2024 11:19:03 +01:00
perf/x86/amd/core: Update and fix stalled-cycles-* events for Zen 2 and later
AMD processors based on Zen 2 and later microarchitectures do not
support PMCx087 (instruction pipe stalls) which is used as the backing
event for "stalled-cycles-frontend" and "stalled-cycles-backend".
Use PMCx0A9 (cycles where micro-op queue is empty) instead to count
frontend stalls and remove the entry for backend stalls since there
is no direct replacement.
Signed-off-by: Sandipan Das <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/03d7fc8fa2a28f9be732116009025bdec1b3ec97.1711352180.git.sandipan.das@amd.com
---
arch/x86/events/amd/core.c | 20 +++++++++++++++++---
1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index 5692e82..af8add6 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -250,7 +250,7 @@ static const u64 amd_perfmon_event_map[PERF_COUNT_HW_MAX] =
/*
* AMD Performance Monitor Family 17h and later:
*/
-static const u64 amd_f17h_perfmon_event_map[PERF_COUNT_HW_MAX] =
+static const u64 amd_zen1_perfmon_event_map[PERF_COUNT_HW_MAX] =
{
[PERF_COUNT_HW_CPU_CYCLES] = 0x0076,
[PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,
@@ -262,10 +262,24 @@ static const u64 amd_f17h_perfmon_event_map[PERF_COUNT_HW_MAX] =
[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = 0x0187,
};
+static const u64 amd_zen2_perfmon_event_map[PERF_COUNT_HW_MAX] =
+{
+ [PERF_COUNT_HW_CPU_CYCLES] = 0x0076,
+ [PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,
+ [PERF_COUNT_HW_CACHE_REFERENCES] = 0xff60,
+ [PERF_COUNT_HW_CACHE_MISSES] = 0x0964,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x00c2,
+ [PERF_COUNT_HW_BRANCH_MISSES] = 0x00c3,
+ [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = 0x00a9,
+};
+
static u64 amd_pmu_event_map(int hw_event)
{
- if (boot_cpu_data.x86 >= 0x17)
- return amd_f17h_perfmon_event_map[hw_event];
+ if (cpu_feature_enabled(X86_FEATURE_ZEN2) || boot_cpu_data.x86 >= 0x19)
+ return amd_zen2_perfmon_event_map[hw_event];
+
+ if (cpu_feature_enabled(X86_FEATURE_ZEN1))
+ return amd_zen1_perfmon_event_map[hw_event];
return amd_perfmon_event_map[hw_event];
}