Re: [PATCH 3/8] perf test: Use a test program in perf record tests

From: Arnaldo Carvalho de Melo
Date: Mon Oct 24 2022 - 07:34:52 EST


Em Thu, Oct 20, 2022 at 04:52:14PM -0700, Ian Rogers escreveu:
> On Thu, Oct 20, 2022 at 10:26 AM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:

> > If the system has cc it could build a test program with two threads
> > and then use it for more detailed testing. Also it accepts an option
> > to run a thread forever to ensure multi-thread runs.
> >
> > If cc is not found, it falls back to use the default value 'true'.
> >
> > Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
>
> Acked-by: Ian Rogers <irogers@xxxxxxxxxx>
>
> I wonder if these utilities should just be built into perf to avoid
> the cc dependency. Perhaps we can have a hidden option built into perf
> test.

Agreed, not depending on a compiler makes 'perf test' usable in more
systems, particularly production ones where we may want to check if perf
is passing all tests applicable to that system.

- Arnaldo

> Thanks,
> Ian
>
> > ---
> > tools/perf/tests/shell/record.sh | 64 ++++++++++++++++++++++++++++++--
> > 1 file changed, 60 insertions(+), 4 deletions(-)
> >
> > diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh
> > index 464071462809..952981481239 100755
> > --- a/tools/perf/tests/shell/record.sh
> > +++ b/tools/perf/tests/shell/record.sh
> > @@ -6,10 +6,17 @@ set -e
> >
> > err=0
> > perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX)
> > +testprog=$(mktemp /tmp/__perf_test.prog.XXXXXX)
> > +testsym="test_loop"
> >
> > cleanup() {
> > rm -f "${perfdata}"
> > rm -f "${perfdata}".old
> > +
> > + if [ "${testprog}" != "true" ]; then
> > + rm -f "${testprog}"
> > + fi
> > +
> > trap - EXIT TERM INT
> > }
> >
> > @@ -19,9 +26,56 @@ trap_cleanup() {
> > }
> > trap trap_cleanup EXIT TERM INT
> >
> > +build_test_program() {
> > + if ! [ -x "$(command -v cc)" ]; then
> > + # No CC found. Fall back to 'true'
> > + testprog=true
> > + testsym=true
> > + return
> > + fi
> > +
> > + echo "Build a test program"
> > + cat <<EOF | cc -o ${testprog} -xc - -pthread
> > +#include <stdio.h>
> > +#include <stdlib.h>
> > +#include <pthread.h>
> > +
> > +void test_loop(void) {
> > + volatile int count = 1000000;
> > +
> > + while (count--)
> > + continue;
> > +}
> > +
> > +void *thfunc(void *arg) {
> > + int forever = *(int *)arg;
> > +
> > + do {
> > + test_loop();
> > + } while (forever);
> > +
> > + return NULL;
> > +}
> > +
> > +int main(int argc, char *argv[]) {
> > + pthread_t th;
> > + int forever = 0;
> > +
> > + if (argc > 1)
> > + forever = atoi(argv[1]);
> > +
> > + pthread_create(&th, NULL, thfunc, &forever);
> > + test_loop();
> > + pthread_join(th, NULL);
> > +
> > + return 0;
> > +}
> > +EOF
> > +}
> > +
> > test_per_thread() {
> > echo "Basic --per-thread mode test"
> > - if ! perf record -o /dev/null --quiet true 2> /dev/null
> > + if ! perf record -o /dev/null --quiet ${testprog} 2> /dev/null
> > then
> > echo "Per-thread record [Skipped event not supported]"
> > if [ $err -ne 1 ]
> > @@ -30,13 +84,13 @@ test_per_thread() {
> > fi
> > return
> > fi
> > - if ! perf record --per-thread -o "${perfdata}" true 2> /dev/null
> > + if ! perf record --per-thread -o "${perfdata}" ${testprog} 2> /dev/null
> > then
> > echo "Per-thread record [Failed record]"
> > err=1
> > return
> > fi
> > - if ! perf report -i "${perfdata}" -q | grep -q true
> > + if ! perf report -i "${perfdata}" -q | grep -q "${testsym}"
> > then
> > echo "Per-thread record [Failed missing output]"
> > err=1
> > @@ -62,7 +116,7 @@ test_register_capture() {
> > return
> > fi
> > if ! perf record -o - --intr-regs=di,r8,dx,cx -e br_inst_retired.near_call:p \
> > - -c 1000 --per-thread true 2> /dev/null \
> > + -c 1000 --per-thread ${testprog} 2> /dev/null \
> > | perf script -F ip,sym,iregs -i - 2> /dev/null \
> > | grep -q "DI:"
> > then
> > @@ -73,6 +127,8 @@ test_register_capture() {
> > echo "Register capture test [Success]"
> > }
> >
> > +build_test_program
> > +
> > test_per_thread
> > test_register_capture
> >
> > --
> > 2.38.0.135.g90850a2211-goog
> >

--

- Arnaldo