From: tanze <tanze0x01@163.com>

Perf's instructions event tests on Zhaoxin CPUs may exhibit:

  $perf stat -e instructions,cycles ls -l

  ......
  Performance counter stats for 'ls -l':

                 0      instructions                     #    0.00  insn per cycle
         9,488,278      cycles

       0.004365407 seconds time elapsed

       0.003303000 seconds user
       0.001099000 seconds sys

The absence of the fixedctr member leads to an incorrect hwc->event_base
value on Zhaoxin CPUs, causing a discrepancy in the instruction count
reported by perf stat. This commit resolves the instruction count issue
by properly initializing the fixedctr member.

Fixes: 149fd4712bcd ("perf/x86/intel: Support Perfmon MSRs aliasing")
Signed-off-by: tanze <tanze0x01@163.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>

---
v1-v3:https://lore.kernel.org/all/20250620023757.1429898-1-tanze@kylinos.cn/

This patch does not modify the previous code,
Do you have any other suggestions?

---
 arch/x86/events/zhaoxin/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/events/zhaoxin/core.c b/arch/x86/events/zhaoxin/core.c
index 4bdfcf091200..3fc3f9abece9 100644
--- a/arch/x86/events/zhaoxin/core.c
+++ b/arch/x86/events/zhaoxin/core.c
@@ -467,6 +467,7 @@ static const struct x86_pmu zhaoxin_pmu __initconst = {
 	.schedule_events	= x86_schedule_events,
 	.eventsel		= MSR_ARCH_PERFMON_EVENTSEL0,
 	.perfctr		= MSR_ARCH_PERFMON_PERFCTR0,
+	.fixedctr		= MSR_ARCH_PERFMON_FIXED_CTR0,
 	.event_map		= zhaoxin_pmu_event_map,
 	.max_events		= ARRAY_SIZE(zx_pmon_event_map),
 	.apic			= 1,
-- 
2.25.1

在 2025/8/14 17:33, tanze0x01@163.com 写道:
> From: tanze <tanze0x01@163.com>
> 
> Perf's instructions event tests on Zhaoxin CPUs may exhibit:
> 
>    $perf stat -e instructions,cycles ls -l
> 
>    ......
>    Performance counter stats for 'ls -l':
> 
>                   0      instructions                     #    0.00  insn per cycle
>           9,488,278      cycles
> 
>         0.004365407 seconds time elapsed
> 
>         0.003303000 seconds user
>         0.001099000 seconds sys
> 
> The absence of the fixedctr member leads to an incorrect hwc->event_base
> value on Zhaoxin CPUs, causing a discrepancy in the instruction count
> reported by perf stat. This commit resolves the instruction count issue
> by properly initializing the fixedctr member.
> 
> Fixes: 149fd4712bcd ("perf/x86/intel: Support Perfmon MSRs aliasing")
> Signed-off-by: tanze <tanze0x01@163.com>
> Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
> 
> ---
> v1-v3:https://lore.kernel.org/all/20250620023757.1429898-1-tanze@kylinos.cn/
> 
> This patch does not modify the previous code,
> Do you have any other suggestions?
> 
Hi peterz,

This is a friendly ping on this patch.

It has been reviewed by Kan Liang a couple of months ago. Is there 
anything I can do to help get it merged?

Thanks,