2022-07-05 15:27:00

by German Gomez

[permalink] [raw]
Subject: [PATCH v2 1/1] perf test: Add test for branch stack sampling

Add a self test for branch stack sampling, to check that we get the
expected branch types, and filters behave as expected.

Suggested-by: Anshuman Khandual <[email protected]>
Signed-off-by: German Gomez <[email protected]>
---
tools/perf/tests/shell/test_brstack.sh | 114 +++++++++++++++++++++++++
1 file changed, 114 insertions(+)
create mode 100755 tools/perf/tests/shell/test_brstack.sh

diff --git a/tools/perf/tests/shell/test_brstack.sh b/tools/perf/tests/shell/test_brstack.sh
new file mode 100755
index 000000000..5f6f40a77
--- /dev/null
+++ b/tools/perf/tests/shell/test_brstack.sh
@@ -0,0 +1,114 @@
+#!/bin/sh
+# Check branch stack sampling
+
+# SPDX-License-Identifier: GPL-2.0
+# German Gomez <[email protected]>, 2022
+
+# we need a C compiler to build the test programs
+# so bail if none is found
+if ! [ -x "$(command -v cc)" ]; then
+ echo "failed: no compiler, install gcc"
+ exit 2
+fi
+
+# skip the test if the hardware doesn't support branch stack sampling
+perf record -b -o- -e dummy -B true > /dev/null 2>&1 || exit 2
+
+TMPDIR=$(mktemp -d /tmp/__perf_test.program.XXXXX)
+
+cleanup() {
+ rm -rf $TMPDIR
+}
+
+trap cleanup exit term int
+
+gen_test_program() {
+ # generate test program
+ cat << EOF > $1
+#define BENCH_RUNS 999999
+int cnt;
+void bar(void) {
+} /* return */
+void foo(void) {
+ bar(); /* call */
+} /* return */
+void bench(void) {
+ void (*foo_ind)(void) = foo;
+ if ((cnt++) % 3) /* branch (cond) */
+ foo(); /* call */
+ bar(); /* call */
+ foo_ind(); /* call (ind) */
+}
+int main(void)
+{
+ int cnt = 0;
+ while (1) {
+ if ((cnt++) > BENCH_RUNS)
+ break;
+ bench(); /* call */
+ } /* branch (uncond) */
+ return 0;
+}
+EOF
+}
+
+test_user_branches() {
+ echo "Testing user branch stack sampling"
+
+ gen_test_program "$TEMPDIR/program.c"
+ cc -fno-inline -g "$TEMPDIR/program.c" -o $TMPDIR/a.out
+
+ perf record -o $TMPDIR/perf.data --branch-filter any,save_type,u -- $TMPDIR/a.out > /dev/null 2>&1
+ perf script -i $TMPDIR/perf.data --fields brstacksym | xargs -n1 > $TMPDIR/perf.script
+
+ # example of branch entries:
+ # foo+0x14/bar+0x40/P/-/-/0/CALL
+
+ set -x
+ egrep -m1 "^bench\+[^ ]*/foo\+[^ ]*/IND_CALL$" $TMPDIR/perf.script
+ egrep -m1 "^foo\+[^ ]*/bar\+[^ ]*/CALL$" $TMPDIR/perf.script
+ egrep -m1 "^bench\+[^ ]*/foo\+[^ ]*/CALL$" $TMPDIR/perf.script
+ egrep -m1 "^bench\+[^ ]*/bar\+[^ ]*/CALL$" $TMPDIR/perf.script
+ egrep -m1 "^bar\+[^ ]*/foo\+[^ ]*/RET$" $TMPDIR/perf.script
+ egrep -m1 "^foo\+[^ ]*/bench\+[^ ]*/RET$" $TMPDIR/perf.script
+ egrep -m1 "^bench\+[^ ]*/bench\+[^ ]*/COND$" $TMPDIR/perf.script
+ egrep -m1 "^main\+[^ ]*/main\+[^ ]*/UNCOND$" $TMPDIR/perf.script
+ set +x
+
+ # some branch types are still not being tested:
+ # IND COND_CALL COND_RET SYSCALL SYSRET IRQ SERROR NO_TX
+}
+
+# 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() {
+ local filter=$1
+ local expect=$2
+
+ echo "Testing branch stack filtering permutation ($filter,$expect)"
+
+ gen_test_program "$TEMPDIR/program.c"
+ cc -fno-inline -g "$TEMPDIR/program.c" -o $TMPDIR/a.out
+
+ perf record -o $TMPDIR/perf.data --branch-filter $filter,save_type,u -- $TMPDIR/a.out > /dev/null 2>&1
+ perf script -i $TMPDIR/perf.data --fields brstack | xargs -n1 > $TMPDIR/perf.script
+
+ # fail if we find any branch type that doesn't match any of the expected ones
+ # also consider UNKNOWN branch types (-)
+ if egrep -vm1 "^[^ ]*/($expect|-|( *))$" $TMPDIR/perf.script; then
+ return 1
+ fi
+}
+
+set -e
+
+test_user_branches
+
+test_filter "any_call" "CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"
+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"
--
2.25.1


2022-07-08 20:34:38

by Namhyung Kim

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] perf test: Add test for branch stack sampling

Hello,

On Tue, Jul 5, 2022 at 8:05 AM German Gomez <[email protected]> wrote:
>
> Add a self test for branch stack sampling, to check that we get the
> expected branch types, and filters behave as expected.
>
> Suggested-by: Anshuman Khandual <[email protected]>
> Signed-off-by: German Gomez <[email protected]>

Acked-by: Namhyung Kim <[email protected]>

Thanks,
Namhyung

2022-07-11 13:00:39

by German Gomez

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] perf test: Add test for branch stack sampling


On 08/07/2022 21:31, Namhyung Kim wrote:
> Hello,
>
> On Tue, Jul 5, 2022 at 8:05 AM German Gomez <[email protected]> wrote:
>> Add a self test for branch stack sampling, to check that we get the
>> expected branch types, and filters behave as expected.
>>
>> Suggested-by: Anshuman Khandual <[email protected]>
>> Signed-off-by: German Gomez <[email protected]>
> Acked-by: Namhyung Kim <[email protected]>

Thanks a lot Namhyung!

>
> Thanks,
> Namhyung

2022-07-11 21:11:28

by Jiri Olsa

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] perf test: Add test for branch stack sampling

On Tue, Jul 05, 2022 at 04:05:11PM +0100, German Gomez wrote:
> Add a self test for branch stack sampling, to check that we get the
> expected branch types, and filters behave as expected.
>
> Suggested-by: Anshuman Khandual <[email protected]>
> Signed-off-by: German Gomez <[email protected]>

Tested-by: Jiri Olsa <[email protected]>

thanks,
jirka

> ---
> tools/perf/tests/shell/test_brstack.sh | 114 +++++++++++++++++++++++++
> 1 file changed, 114 insertions(+)
> create mode 100755 tools/perf/tests/shell/test_brstack.sh
>
> diff --git a/tools/perf/tests/shell/test_brstack.sh b/tools/perf/tests/shell/test_brstack.sh
> new file mode 100755
> index 000000000..5f6f40a77
> --- /dev/null
> +++ b/tools/perf/tests/shell/test_brstack.sh
> @@ -0,0 +1,114 @@
> +#!/bin/sh
> +# Check branch stack sampling
> +
> +# SPDX-License-Identifier: GPL-2.0
> +# German Gomez <[email protected]>, 2022
> +
> +# we need a C compiler to build the test programs
> +# so bail if none is found
> +if ! [ -x "$(command -v cc)" ]; then
> + echo "failed: no compiler, install gcc"
> + exit 2
> +fi
> +
> +# skip the test if the hardware doesn't support branch stack sampling
> +perf record -b -o- -e dummy -B true > /dev/null 2>&1 || exit 2
> +
> +TMPDIR=$(mktemp -d /tmp/__perf_test.program.XXXXX)
> +
> +cleanup() {
> + rm -rf $TMPDIR
> +}
> +
> +trap cleanup exit term int
> +
> +gen_test_program() {
> + # generate test program
> + cat << EOF > $1
> +#define BENCH_RUNS 999999
> +int cnt;
> +void bar(void) {
> +} /* return */
> +void foo(void) {
> + bar(); /* call */
> +} /* return */
> +void bench(void) {
> + void (*foo_ind)(void) = foo;
> + if ((cnt++) % 3) /* branch (cond) */
> + foo(); /* call */
> + bar(); /* call */
> + foo_ind(); /* call (ind) */
> +}
> +int main(void)
> +{
> + int cnt = 0;
> + while (1) {
> + if ((cnt++) > BENCH_RUNS)
> + break;
> + bench(); /* call */
> + } /* branch (uncond) */
> + return 0;
> +}
> +EOF
> +}
> +
> +test_user_branches() {
> + echo "Testing user branch stack sampling"
> +
> + gen_test_program "$TEMPDIR/program.c"
> + cc -fno-inline -g "$TEMPDIR/program.c" -o $TMPDIR/a.out
> +
> + perf record -o $TMPDIR/perf.data --branch-filter any,save_type,u -- $TMPDIR/a.out > /dev/null 2>&1
> + perf script -i $TMPDIR/perf.data --fields brstacksym | xargs -n1 > $TMPDIR/perf.script
> +
> + # example of branch entries:
> + # foo+0x14/bar+0x40/P/-/-/0/CALL
> +
> + set -x
> + egrep -m1 "^bench\+[^ ]*/foo\+[^ ]*/IND_CALL$" $TMPDIR/perf.script
> + egrep -m1 "^foo\+[^ ]*/bar\+[^ ]*/CALL$" $TMPDIR/perf.script
> + egrep -m1 "^bench\+[^ ]*/foo\+[^ ]*/CALL$" $TMPDIR/perf.script
> + egrep -m1 "^bench\+[^ ]*/bar\+[^ ]*/CALL$" $TMPDIR/perf.script
> + egrep -m1 "^bar\+[^ ]*/foo\+[^ ]*/RET$" $TMPDIR/perf.script
> + egrep -m1 "^foo\+[^ ]*/bench\+[^ ]*/RET$" $TMPDIR/perf.script
> + egrep -m1 "^bench\+[^ ]*/bench\+[^ ]*/COND$" $TMPDIR/perf.script
> + egrep -m1 "^main\+[^ ]*/main\+[^ ]*/UNCOND$" $TMPDIR/perf.script
> + set +x
> +
> + # some branch types are still not being tested:
> + # IND COND_CALL COND_RET SYSCALL SYSRET IRQ SERROR NO_TX
> +}
> +
> +# 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() {
> + local filter=$1
> + local expect=$2
> +
> + echo "Testing branch stack filtering permutation ($filter,$expect)"
> +
> + gen_test_program "$TEMPDIR/program.c"
> + cc -fno-inline -g "$TEMPDIR/program.c" -o $TMPDIR/a.out
> +
> + perf record -o $TMPDIR/perf.data --branch-filter $filter,save_type,u -- $TMPDIR/a.out > /dev/null 2>&1
> + perf script -i $TMPDIR/perf.data --fields brstack | xargs -n1 > $TMPDIR/perf.script
> +
> + # fail if we find any branch type that doesn't match any of the expected ones
> + # also consider UNKNOWN branch types (-)
> + if egrep -vm1 "^[^ ]*/($expect|-|( *))$" $TMPDIR/perf.script; then
> + return 1
> + fi
> +}
> +
> +set -e
> +
> +test_user_branches
> +
> +test_filter "any_call" "CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"
> +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"
> --
> 2.25.1
>

2022-07-12 08:14:35

by German Gomez

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] perf test: Add test for branch stack sampling


On 11/07/2022 21:56, Jiri Olsa wrote:
> On Tue, Jul 05, 2022 at 04:05:11PM +0100, German Gomez wrote:
>> Add a self test for branch stack sampling, to check that we get the
>> expected branch types, and filters behave as expected.
>>
>> Suggested-by: Anshuman Khandual <[email protected]>
>> Signed-off-by: German Gomez <[email protected]>
> Tested-by: Jiri Olsa <[email protected]>

Thanks a lot, Jiri!

>
> thanks,
> jirka
>
>> ---
>> tools/perf/tests/shell/test_brstack.sh | 114 +++++++++++++++++++++++++
>> 1 file changed, 114 insertions(+)
>> create mode 100755 tools/perf/tests/shell/test_brstack.sh
>>
>> diff --git a/tools/perf/tests/shell/test_brstack.sh b/tools/perf/tests/shell/test_brstack.sh
>> new file mode 100755
>> index 000000000..5f6f40a77
>> --- /dev/null
>> +++ b/tools/perf/tests/shell/test_brstack.sh
>> @@ -0,0 +1,114 @@
>> +#!/bin/sh
>> +# Check branch stack sampling
>> +
>> +# SPDX-License-Identifier: GPL-2.0
>> +# German Gomez <[email protected]>, 2022
>> +
>> +# we need a C compiler to build the test programs
>> +# so bail if none is found
>> +if ! [ -x "$(command -v cc)" ]; then
>> + echo "failed: no compiler, install gcc"
>> + exit 2
>> +fi
>> +
>> +# skip the test if the hardware doesn't support branch stack sampling
>> +perf record -b -o- -e dummy -B true > /dev/null 2>&1 || exit 2
>> +
>> +TMPDIR=$(mktemp -d /tmp/__perf_test.program.XXXXX)
>> +
>> +cleanup() {
>> + rm -rf $TMPDIR
>> +}
>> +
>> +trap cleanup exit term int
>> +
>> +gen_test_program() {
>> + # generate test program
>> + cat << EOF > $1
>> +#define BENCH_RUNS 999999
>> +int cnt;
>> +void bar(void) {
>> +} /* return */
>> +void foo(void) {
>> + bar(); /* call */
>> +} /* return */
>> +void bench(void) {
>> + void (*foo_ind)(void) = foo;
>> + if ((cnt++) % 3) /* branch (cond) */
>> + foo(); /* call */
>> + bar(); /* call */
>> + foo_ind(); /* call (ind) */
>> +}
>> +int main(void)
>> +{
>> + int cnt = 0;
>> + while (1) {
>> + if ((cnt++) > BENCH_RUNS)
>> + break;
>> + bench(); /* call */
>> + } /* branch (uncond) */
>> + return 0;
>> +}
>> +EOF
>> +}
>> +
>> +test_user_branches() {
>> + echo "Testing user branch stack sampling"
>> +
>> + gen_test_program "$TEMPDIR/program.c"
>> + cc -fno-inline -g "$TEMPDIR/program.c" -o $TMPDIR/a.out
>> +
>> + perf record -o $TMPDIR/perf.data --branch-filter any,save_type,u -- $TMPDIR/a.out > /dev/null 2>&1
>> + perf script -i $TMPDIR/perf.data --fields brstacksym | xargs -n1 > $TMPDIR/perf.script
>> +
>> + # example of branch entries:
>> + # foo+0x14/bar+0x40/P/-/-/0/CALL
>> +
>> + set -x
>> + egrep -m1 "^bench\+[^ ]*/foo\+[^ ]*/IND_CALL$" $TMPDIR/perf.script
>> + egrep -m1 "^foo\+[^ ]*/bar\+[^ ]*/CALL$" $TMPDIR/perf.script
>> + egrep -m1 "^bench\+[^ ]*/foo\+[^ ]*/CALL$" $TMPDIR/perf.script
>> + egrep -m1 "^bench\+[^ ]*/bar\+[^ ]*/CALL$" $TMPDIR/perf.script
>> + egrep -m1 "^bar\+[^ ]*/foo\+[^ ]*/RET$" $TMPDIR/perf.script
>> + egrep -m1 "^foo\+[^ ]*/bench\+[^ ]*/RET$" $TMPDIR/perf.script
>> + egrep -m1 "^bench\+[^ ]*/bench\+[^ ]*/COND$" $TMPDIR/perf.script
>> + egrep -m1 "^main\+[^ ]*/main\+[^ ]*/UNCOND$" $TMPDIR/perf.script
>> + set +x
>> +
>> + # some branch types are still not being tested:
>> + # IND COND_CALL COND_RET SYSCALL SYSRET IRQ SERROR NO_TX
>> +}
>> +
>> +# 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() {
>> + local filter=$1
>> + local expect=$2
>> +
>> + echo "Testing branch stack filtering permutation ($filter,$expect)"
>> +
>> + gen_test_program "$TEMPDIR/program.c"
>> + cc -fno-inline -g "$TEMPDIR/program.c" -o $TMPDIR/a.out
>> +
>> + perf record -o $TMPDIR/perf.data --branch-filter $filter,save_type,u -- $TMPDIR/a.out > /dev/null 2>&1
>> + perf script -i $TMPDIR/perf.data --fields brstack | xargs -n1 > $TMPDIR/perf.script
>> +
>> + # fail if we find any branch type that doesn't match any of the expected ones
>> + # also consider UNKNOWN branch types (-)
>> + if egrep -vm1 "^[^ ]*/($expect|-|( *))$" $TMPDIR/perf.script; then
>> + return 1
>> + fi
>> +}
>> +
>> +set -e
>> +
>> +test_user_branches
>> +
>> +test_filter "any_call" "CALL|IND_CALL|COND_CALL|SYSCALL|IRQ"
>> +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"
>> --
>> 2.25.1
>>

2022-07-12 12:15:27

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] perf test: Add test for branch stack sampling

Em Fri, Jul 08, 2022 at 01:31:43PM -0700, Namhyung Kim escreveu:
> Hello,
>
> On Tue, Jul 5, 2022 at 8:05 AM German Gomez <[email protected]> wrote:
> >
> > Add a self test for branch stack sampling, to check that we get the
> > expected branch types, and filters behave as expected.
> >
> > Suggested-by: Anshuman Khandual <[email protected]>
> > Signed-off-by: German Gomez <[email protected]>
>
> Acked-by: Namhyung Kim <[email protected]>

Thanks, applied.

- Arnaldo