Commit 9f0fa213 authored by James Clark's avatar James Clark Committed by Arnaldo Carvalho de Melo
Browse files

perf test: Extend branch stack sampling test for Arm64 BRBE 



BRBE emits IRQ and ERET branches for branching and returning from
trapped instructions. Add a test that loops on a trapped instruction
(MRS - Read special register) for this.

Extend the expected 'any_call' branches to include FAULT_DATA and
FAULT_INST as these are emitted by BRBE.

Reviewed-by: default avatarIan Rogers <irogers@google.com>
Co-developed-by: default avatarGerman Gomez <german.gomez@arm.com>
Signed-off-by: default avatarGerman Gomez <german.gomez@arm.com>
Signed-off-by: default avatarJames Clark <james.clark@linaro.org>
Cc: Adam Young <admiyo@os.amperecomputing.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 11e59335

tools/perf/tests/builtin-test.c

+1 −0
Original line number Diff line number Diff line
@@ -152,6 +152,7 @@ static struct test_workload *workloads[] = { 
	&workload__brstack,

	&workload__datasym,

	&workload__landlock,

	&workload__traploop,

};



#define workloads__for_each(workload) \

tools/perf/tests/shell/test_brstack.sh

+25 −1
Original line number Diff line number Diff line
@@ -34,6 +34,10 @@ trap_cleanup() { 
}

trap trap_cleanup EXIT TERM INT



is_arm64() {

	[ "$(uname -m)" = "aarch64" ];

}



check_branches() {

	if ! tr -s ' ' '\n' < "$TMPDIR/perf.script" | grep -E -m1 -q "$1"; then

		echo "Branches missing $1"
@@ -76,9 +80,24 @@ test_user_branches() { 
		err=1

	fi

	# some branch types are still not being tested:

	# IND COND_CALL COND_RET SYSRET IRQ SERROR NO_TX

	# IND COND_CALL COND_RET SYSRET SERROR NO_TX

}



test_trap_eret_branches() {

	echo "Testing trap & eret branches"

	if ! is_arm64; then

		echo "skip: not arm64"

	else

		perf record -o $TMPDIR/perf.data --branch-filter any,save_type,u,k -- \

			perf test -w traploop 1000

		perf script -i $TMPDIR/perf.data --fields brstacksym | \

			tr ' ' '\n' > $TMPDIR/perf.script



		# BRBINF<n>.TYPE == TRAP are mapped to PERF_BR_IRQ by the BRBE driver

		check_branches "^trap_bench\+[^ ]+/[^ ]/IRQ/"

		check_branches "^[^ ]+/trap_bench\+[^ ]+/ERET/"

	fi

}



test_kernel_branches() {

	echo "Testing that k option only includes kernel source addresses"
@@ -162,9 +181,14 @@ set -e 
test_user_branches

test_syscall

test_kernel_branches

test_trap_eret_branches



any_call="CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"



if is_arm64; then

	any_call="$any_call|FAULT_DATA|FAULT_INST"

fi



test_filter "any_call" "$any_call"

test_filter "call"	"CALL|SYSCALL"

test_filter "cond"	"COND"

tools/perf/tests/tests.h

+1 −0
Original line number Diff line number Diff line
@@ -239,6 +239,7 @@ DECLARE_WORKLOAD(sqrtloop); 
DECLARE_WORKLOAD(brstack);

DECLARE_WORKLOAD(datasym);

DECLARE_WORKLOAD(landlock);

DECLARE_WORKLOAD(traploop);



extern const char *dso_to_test;

extern const char *test_objdump_path;

tools/perf/tests/workloads/Build

+2 −0
Original line number Diff line number Diff line
@@ -7,8 +7,10 @@ perf-test-y += sqrtloop.o 
perf-test-y += brstack.o

perf-test-y += datasym.o

perf-test-y += landlock.o

perf-test-y += traploop.o



CFLAGS_sqrtloop.o         = -g -O0 -fno-inline -U_FORTIFY_SOURCE

CFLAGS_leafloop.o         = -g -O0 -fno-inline -fno-omit-frame-pointer -U_FORTIFY_SOURCE

CFLAGS_brstack.o          = -g -O0 -fno-inline -U_FORTIFY_SOURCE

CFLAGS_datasym.o          = -g -O0 -fno-inline -U_FORTIFY_SOURCE

CFLAGS_traploop.o         = -g -O0 -fno-inline -U_FORTIFY_SOURCE

tools/perf/tests/workloads/traploop.c

0 → 100644
+31 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#include <stdlib.h>

#include "../tests.h"



#define BENCH_RUNS 999999



#ifdef __aarch64__

static void trap_bench(void)

{

	unsigned long val;



	asm("mrs %0, ID_AA64ISAR0_EL1" : "=r" (val));   /* TRAP + ERET */

}

#else

static void trap_bench(void) { }

#endif



static int traploop(int argc, const char **argv)

{

	int num_loops = BENCH_RUNS;



	if (argc > 0)

		num_loops = atoi(argv[0]);



	for (int i = 0; i < num_loops; i++)

		trap_bench();



	return 0;

}



DEFINE_WORKLOAD(traploop);