From 2c70d0086e4e9e2440f0f78098090f32bde14277 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Tue, 4 Nov 2014 21:56:10 -0500 Subject: [PATCH] perf/x86/intel: Disable FREEZE_LBRS_ON_PMI when LBR operates in callstack mode LBR callstack is designed for PEBS, It does not work well with FREEZE_LBRS_ON_PMI for non PEBS event. If FREEZE_LBRS_ON_PMI is set for non PEBS event, PMIs near call/return instructions may cause superfluous increase/decrease of LBR_TOS. This patch modifies __intel_pmu_lbr_enable() to not enable FREEZE_LBRS_ON_PMI when LBR operates in callstack mode. We currently don't use LBR callstack to capture kernel space callchain, so disabling FREEZE_LBRS_ON_PMI should not be a problem. Signed-off-by: Yan, Zheng Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Cc: Paul Mackerras Cc: eranian@google.com Cc: jolsa@redhat.com Link: http://lkml.kernel.org/r/1415156173-10035-15-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar --- Reading git-format-patch failed