[PATCH 01/15] perf/x86/lbr: Simplify the exposure check for the LBR_INFO registers

Yang Weijiang posted 15 patches 3 years, 7 months ago
There is a newer version of this series
[PATCH 01/15] perf/x86/lbr: Simplify the exposure check for the LBR_INFO registers
Posted by Yang Weijiang 3 years, 7 months ago
From: Like Xu <like.xu@linux.intel.com>

The x86_pmu.lbr_info is 0 unless explicitly initialized, so there's
no point checking x86_pmu.intel_cap.lbr_format.

Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
Message-Id: <20220517154100.29983-3-weijiang.yang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/events/intel/lbr.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c
index 4f70fb6c2c1e..4ed6d3691e10 100644
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -1873,12 +1873,10 @@ void __init intel_pmu_arch_lbr_init(void)
  */
 int x86_perf_get_lbr(struct x86_pmu_lbr *lbr)
 {
-	int lbr_fmt = x86_pmu.intel_cap.lbr_format;
-
 	lbr->nr = x86_pmu.lbr_nr;
 	lbr->from = x86_pmu.lbr_from;
 	lbr->to = x86_pmu.lbr_to;
-	lbr->info = (lbr_fmt == LBR_FORMAT_INFO) ? x86_pmu.lbr_info : 0;
+	lbr->info = x86_pmu.lbr_info;
 
 	return 0;
 }
-- 
2.27.0
Re: [PATCH 01/15] perf/x86/lbr: Simplify the exposure check for the LBR_INFO registers
Posted by Sean Christopherson 3 years, 7 months ago
On Wed, Aug 31, 2022, Yang Weijiang wrote:
> From: Like Xu <like.xu@linux.intel.com>
> 
> The x86_pmu.lbr_info is 0 unless explicitly initialized, so there's
> no point checking x86_pmu.intel_cap.lbr_format.
> 
> Cc: Peter Zijlstra <peterz@infradead.org>
> Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
> Reviewed-by: Andi Kleen <ak@linux.intel.com>
> Signed-off-by: Like Xu <like.xu@linux.intel.com>
> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
> Message-Id: <20220517154100.29983-3-weijiang.yang@intel.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---

No need to carry Paolo's SOB for patches that Paolo temporarily queued.  And please
delete the "Message-Id" entries as well.
Re: [PATCH 01/15] perf/x86/lbr: Simplify the exposure check for the LBR_INFO registers
Posted by Yang, Weijiang 3 years, 7 months ago
On 9/1/2022 10:19 PM, Sean Christopherson wrote:
> On Wed, Aug 31, 2022, Yang Weijiang wrote:
>> From: Like Xu <like.xu@linux.intel.com>
>>
>> The x86_pmu.lbr_info is 0 unless explicitly initialized, so there's
>> no point checking x86_pmu.intel_cap.lbr_format.
>>
>> Cc: Peter Zijlstra <peterz@infradead.org>
>> Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
>> Reviewed-by: Andi Kleen <ak@linux.intel.com>
>> Signed-off-by: Like Xu <like.xu@linux.intel.com>
>> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
>> Message-Id: <20220517154100.29983-3-weijiang.yang@intel.com>
>> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>> ---
> No need to carry Paolo's SOB for patches that Paolo temporarily queued.  And please
> delete the "Message-Id" entries as well.
Sure, will remove them, thanks!