bd657aa3dd
CPUID.(EAX=07H, ECX=0):EDX[19] indicates whether an Intel CPU supports Architectural LBRs. The "X86_FEATURE_..., word 18" is already mirrored from CPUID "0x00000007:0 (EDX)". Add X86_FEATURE_ARCH_LBR under the "word 18" section. The feature will appear as "arch_lbr" in /proc/cpuinfo. The Architectural Last Branch Records (LBR) feature enables recording of software path history by logging taken branches and other control flows. The feature will be supported in the perf_events subsystem. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dave Hansen <dave.hansen@intel.com> Link: https://lkml.kernel.org/r/1593780569-62993-2-git-send-email-kan.liang@linux.intel.com