[PATCH 2/6] perf/x86/lbr: Unify LBR_INFO registers exposure check condition

Like Xu
2020-07-31T07:46:17Z

Architectural LBR has IA32_LBR_x_INFO instead of LBR_FORMAT_INFO_x
to hold metadata for the operation, including mispredict, TSX, and
elapsed cycle time information.

The x86_pmu.lbr_info will be assigned in intel_pmu_?_lbr_init_?(),
it's safe to expose LBR_INFO in the x86_perf_get_lbr(), instead of
relying solely on 'lbr_format == LBR_FORMAT_INFO' check.

Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Like Xu <like.xu@linux.intel.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 63f58bdf556c..8d816f580342 100644
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -1832,12 +1832,10 @@ 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;
}
--
2.21.3