Commit faba2f17 authored by James Clark's avatar James Clark Committed by Junhao He
Browse files

perf: test: Extend branch stack sampling test for Arm64 BRBE 

maillist inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8EC9K
CVE: NA

Reference: https://lore.kernel.org/linux-arm-kernel/20240613061731.3109448-1-anshuman.khandual@arm.com/



--------------------------------

Add Arm64 BRBE-specific testing to the existing branch stack sampling test.
The test currently passes on the Arm FVP RevC model, but no hardware has
been tested yet.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: linux-perf-users@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
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@arm.com>
Signed-off-by: default avatarAnshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: default avatarJunhao He <hejunhao3@huawei.com>
parent e9c94f8a

tools/perf/tests/builtin-test.c

+1 −0
Original line number Diff line number Diff line
@@ -139,6 +139,7 @@ static struct test_workload *workloads[] = { 
	&workload__sqrtloop,

	&workload__brstack,

	&workload__datasym,

	&workload__traploop

};



static int num_subtests(const struct test_suite *t)

tools/perf/tests/shell/test_brstack.sh

+39 −3
Original line number Diff line number Diff line
@@ -47,12 +47,43 @@ test_user_branches() { 
	grep -E -m1 "^brstack_foo\+[^ ]*/brstack_bench\+[^ ]*/RET/.*$"	$TMPDIR/perf.script

	grep -E -m1 "^brstack_bench\+[^ ]*/brstack_bench\+[^ ]*/COND/.*$"	$TMPDIR/perf.script

	grep -E -m1 "^brstack\+[^ ]*/brstack\+[^ ]*/UNCOND/.*$"		$TMPDIR/perf.script



	if is_arm64; then

		# in arm64 with BRBE, we get IRQ entries that correspond

		# to any point in the process

		grep -m1 "/IRQ/"					$TMPDIR/perf.script

	fi

	set +x



	# some branch types are still not being tested:

	# IND COND_CALL COND_RET SYSCALL SYSRET IRQ SERROR NO_TX

}



test_arm64_trap_eret_branches() {

	echo "Testing trap & eret branches (arm64 brbe)"

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

		perf test -w traploop 250

	perf script -i $TMPDIR/perf.data --fields brstacksym | tr ' ' '\n' > $TMPDIR/perf.script

	set -x

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

	grep -E -m1 "^trap_bench\+[^ ]*/\[unknown\][^ ]*/SYSCALL/" $TMPDIR/perf.script

	grep -E -m1 "^\[unknown\][^ ]*/trap_bench\+[^ ]*/ERET/"	$TMPDIR/perf.script

	set +x

}



test_arm64_kernel_branches() {

	echo "Testing kernel branches (arm64 brbe)"

	# skip if perf doesn't have enough privileges

	if ! perf record --branch-filter any,k -o- -- true > /dev/null; then

		echo "[skipped: not enough privileges]"

		return 0

	fi

	perf record -o $TMPDIR/perf.data --branch-filter any,k -- uname -a

	perf script -i $TMPDIR/perf.data --fields brstack | tr ' ' '\n' > $TMPDIR/perf.script

	grep -E -m1 "0xffff[0-9a-f]{12}" $TMPDIR/perf.script

	! egrep -E -m1 "0x0000[0-9a-f]{12}" $TMPDIR/perf.script

}



# first argument <arg0> is the argument passed to "--branch-stack <arg0>,save_type,u"

# second argument are the expected branch types for the given filter

test_filter() {
@@ -75,11 +106,16 @@ set -e 


test_user_branches



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

if is_arm64; then

	test_arm64_trap_eret_branches

	test_arm64_kernel_branches

fi



test_filter "any_call"	"CALL|IND_CALL|COND_CALL|SYSCALL|IRQ|FAULT_DATA|FAULT_INST"

test_filter "call"	"CALL|SYSCALL"

test_filter "cond"	"COND"

test_filter "any_ret"	"RET|COND_RET|SYSRET|ERET"



test_filter "call,cond"		"CALL|SYSCALL|COND"

test_filter "any_call,cond"		"CALL|IND_CALL|COND_CALL|IRQ|SYSCALL|COND"

test_filter "cond,any_call,any_ret"	"COND|CALL|IND_CALL|COND_CALL|SYSCALL|IRQ|RET|COND_RET|SYSRET|ERET"
 
test_filter "any_call,cond"		"CALL|IND_CALL|COND_CALL|IRQ|SYSCALL|COND|FAULT_DATA|FAULT_INST"

test_filter "cond,any_call,any_ret"	"COND|CALL|IND_CALL|COND_CALL|SYSCALL|IRQ|RET|COND_RET|SYSRET|ERET|FAULT_DATA|FAULT_INST"

tools/perf/tests/tests.h

+1 −0
Original line number Diff line number Diff line
@@ -205,6 +205,7 @@ DECLARE_WORKLOAD(leafloop); 
DECLARE_WORKLOAD(sqrtloop);

DECLARE_WORKLOAD(brstack);

DECLARE_WORKLOAD(datasym);

DECLARE_WORKLOAD(traploop);



extern const char *dso_to_test;

tools/perf/tests/workloads/Build

+2 −0
Original line number Diff line number Diff line
@@ -6,8 +6,10 @@ perf-y += leafloop.o 
perf-y += sqrtloop.o

perf-y += brstack.o

perf-y += datasym.o

perf-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
+39 −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



static volatile int cnt;



#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]);



	while (1) {

		if ((cnt++) > num_loops)

			break;



		trap_bench();

	}

	return 0;

}



DEFINE_WORKLOAD(traploop);