[PATCH 2/2] perf/x86/intel/lbr: Optimizing context switch for LBR call stack

From: Kan Liang Context switches with perf LBR call stack context are fairly expensive because they do a lot of MSR writes. Currently we unconditionally do the expensive operation when LBR call stack is enabled. It's not necessary for some common cases, e.g task -> other kernel thread -> same

[PATCH 2/2] perf/x86/intel/lbr: Optimizing context switch for LBR call stack

From: Kan Liang Context switches with perf LBR call stack context are fairly expensive because they do a lot of MSR writes. Currently we unconditionally do the expensive operation when LBR call stack is enabled. It's not necessary for some common cases, e.g task -> other kernel thread -> same