mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

perf/x86/amd/core: Define a proper ref-cycles event for Zen 4 and later 

Add the "ref-cycles" event for AMD processors based on Zen 4 and later
microarchitectures. The backing event is based on PMCx120 which counts
cycles not in halt state in P0 frequency (same as MPERF).

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/089155f19f7c7e65aeb1caa727a882e2ca9b8b04.1711352180.git.sandipan.das@amd.com
This commit is contained in:
Sandipan Das 2024-03-25 13:17:54 +05:30 committed by Ingo Molnar
parent c7b2edd837
commit 68cdf1e6e8
1 changed files with 15 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
arch/x86/events/amd/core.c
View File

@ -273,8 +273,23 @@ static const u64 amd_zen2_perfmon_event_map[PERF_COUNT_HW_MAX] =
[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = 0x00a9,
};
static const u64 amd_zen4_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,
[PERF_COUNT_HW_REF_CPU_CYCLES] = 0x100000120,
};
static u64 amd_pmu_event_map(int hw_event)
{
if (cpu_feature_enabled(X86_FEATURE_ZEN4) || boot_cpu_data.x86 >= 0x1a)
return amd_zen4_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];