From 52ca9ced3f70779589e6ecc329baffe69d8f5f7a Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Fri, 30 Jan 2015 12:39:52 +0200 Subject: perf/x86/intel/pt: Add Intel PT PMU driver Add support for Intel Processor Trace (PT) to kernel's perf events. PT is an extension of Intel Architecture that collects information about software execuction such as control flow, execution modes and timings and formats it into highly compressed binary packets. Even being compressed, these packets are generated at hundreds of megabytes per second per core, which makes it impractical to decode them on the fly in the kernel. This driver exports trace data by through AUX space in the perf ring buffer, which is zero-copy mapped into userspace for faster data retrieval. Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Borislav Petkov Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kaixu Xia Cc: Linus Torvalds Cc: Mike Galbraith Cc: Paul Mackerras Cc: Robert Richter Cc: Stephane Eranian Cc: Thomas Gleixner Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: kan.liang@intel.com Cc: markus.t.metzger@intel.com Cc: mathieu.poirier@linaro.org Link: http://lkml.kernel.org/r/1422614392-114498-1-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event_intel.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/x86/kernel/cpu/perf_event_intel.c') diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index b7b3ff21c832..8eb22ce26303 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1589,6 +1589,14 @@ again: x86_pmu.drain_pebs(regs); } + /* + * Intel PT + */ + if (__test_and_clear_bit(55, (unsigned long *)&status)) { + handled++; + intel_pt_interrupt(); + } + /* * Checkpointed counters can lead to 'spurious' PMIs because the * rollback caused by the PMI will have cleared the overflow status -- cgit