Commit e9240355 authored by Adrian Hunter's avatar Adrian Hunter Committed by Arnaldo Carvalho de Melo
Browse files

perf intel-pt: Force 'quick' mode when TNT (Taken/Not-Taken packet) is disabled 



It is not possible to walk the executable code without TNT packets, so
force 'quick' mode when TNT is disabled, because 'quick' mode does not walk
the code.

Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20220124084201.2699795-18-adrian.hunter@intel.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 11f18e47

tools/perf/util/intel-pt.c

+18 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ 
#define INTEL_PT_CFG_PWR_EVT_EN	BIT_ULL(4)

#define INTEL_PT_CFG_BRANCH_EN	BIT_ULL(13)

#define INTEL_PT_CFG_EVT_EN	BIT_ULL(31)

#define INTEL_PT_CFG_TNT_DIS	BIT_ULL(55)



struct range {

	u64 start;
@@ -972,6 +973,19 @@ static bool intel_pt_branch_enable(struct intel_pt *pt) 
	return true;

}



static bool intel_pt_disabled_tnt(struct intel_pt *pt)

{

	struct evsel *evsel;

	u64 config;



	evlist__for_each_entry(pt->session->evlist, evsel) {

		if (intel_pt_get_config(pt, &evsel->core.attr, &config) &&

		    config & INTEL_PT_CFG_TNT_DIS)

			return true;

	}

	return false;

}



static unsigned int intel_pt_mtc_period(struct intel_pt *pt)

{

	struct evsel *evsel;
@@ -1227,6 +1241,10 @@ static struct intel_pt_queue *intel_pt_alloc_queue(struct intel_pt *pt, 
	params.first_timestamp = pt->first_timestamp;

	params.max_loops = pt->max_loops;



	/* Cannot walk code without TNT, so force 'quick' mode */

	if (params.branch_enable && intel_pt_disabled_tnt(pt) && !params.quick)

		params.quick = 1;



	if (pt->filts.cnt > 0)

		params.pgd_ip = intel_pt_pgd_ip;