[PATCH v8 02/15] perf/x86/lbr: Simplify the exposure check for the LBR_INFO registers

From: Yang Weijiang
Date: Tue Aug 24 2021 - 03:41:08 EST


From: Like Xu <like.xu@xxxxxxxxxxxxxxx>

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@xxxxxxxxxxxxx>
Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Signed-off-by: Like Xu <like.xu@xxxxxxxxxxxxxxx>
Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx>
---
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 9e6d6eaeb4cb..ceff16eb4bcb 100644
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -1848,12 +1848,10 @@ 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;
}
--
2.25.1