From 8e105a1fc2a02d78698834974083c980d2e5b513 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Fri, 25 Oct 2019 17:08:34 +0300 Subject: perf/x86/intel/pt: Factor out pt_config_start() PT trace is now enabled at the bottom of the event configuration function that takes care of all configuration bits related to a given event, including the address filter update. This is only needed where the event configuration changes, that is, in ->add()/->start(). In the interrupt path we can use a lighter version that keeps the configuration intact, since it hasn't changed, and only flips the enable bit. Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Jiri Olsa Cc: Linus Torvalds Cc: Mark Rutland Cc: Namhyung Kim Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: adrian.hunter@intel.com Cc: mathieu.poirier@linaro.org Link: https://lkml.kernel.org/r/20191025140835.53665-3-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/events/intel/pt.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) (limited to 'arch') diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 05e43d0f430b..170f3b402274 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -397,6 +397,20 @@ static bool pt_event_valid(struct perf_event *event) * These all are cpu affine and operate on a local PT */ +static void pt_config_start(struct perf_event *event) +{ + struct pt *pt = this_cpu_ptr(&pt_ctx); + u64 ctl = event->hw.config; + + ctl |= RTIT_CTL_TRACEEN; + if (READ_ONCE(pt->vmx_on)) + perf_aux_output_flag(&pt->handle, PERF_AUX_FLAG_PARTIAL); + else + wrmsrl(MSR_IA32_RTIT_CTL, ctl); + + WRITE_ONCE(event->hw.config, ctl); +} + /* Address ranges and their corresponding msr configuration registers */ static const struct pt_address_range { unsigned long msr_a; @@ -468,7 +482,6 @@ static u64 pt_config_filters(struct perf_event *event) static void pt_config(struct perf_event *event) { - struct pt *pt = this_cpu_ptr(&pt_ctx); u64 reg; /* First round: clear STATUS, in particular the PSB byte counter. */ @@ -501,10 +514,7 @@ static void pt_config(struct perf_event *event) reg |= (event->attr.config & PT_CONFIG_MASK); event->hw.config = reg; - if (READ_ONCE(pt->vmx_on)) - perf_aux_output_flag(&pt->handle, PERF_AUX_FLAG_PARTIAL); - else - wrmsrl(MSR_IA32_RTIT_CTL, reg); + pt_config_start(event); } static void pt_config_stop(struct perf_event *event) @@ -1381,7 +1391,7 @@ void intel_pt_interrupt(void) pt_config_buffer(topa_to_page(buf->cur)->table, buf->cur_idx, buf->output_off); - pt_config(event); + pt_config_start(event); } } -- cgit v1.2.3-59-g8ed1b