On Tue, Jun 08, 2021 at 10:40:24PM -0700, Andrii Nakryiko wrote:
> On Sat, Jun 5, 2021 at 4:12 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
> >
> > Adding selftest for fentry multi func test that attaches
> > to bpf_fentry_test* functions and checks argument values
> > based on the processed function.
> >
> > Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> > ---
> > tools/testing/selftests/bpf/multi_check.h | 52 +++++++++++++++++++
> > .../bpf/prog_tests/fentry_multi_test.c | 43 +++++++++++++++
> > .../selftests/bpf/progs/fentry_multi_test.c | 18 +++++++
> > 3 files changed, 113 insertions(+)
> > create mode 100644 tools/testing/selftests/bpf/multi_check.h
> > create mode 100644 tools/testing/selftests/bpf/prog_tests/fentry_multi_test.c
> > create mode 100644 tools/testing/selftests/bpf/progs/fentry_multi_test.c
> >
> > diff --git a/tools/testing/selftests/bpf/multi_check.h b/tools/testing/selftests/bpf/multi_check.h
> > new file mode 100644
> > index 000000000000..36c2a93f9be3
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/multi_check.h
>
> we have a proper static linking now, we don't have to use header
> inclusion hacks, let's do this properly?
ok, will change
>
> > @@ -0,0 +1,52 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +
> > +#ifndef __MULTI_CHECK_H
> > +#define __MULTI_CHECK_H
> > +
> > +extern unsigned long long bpf_fentry_test[8];
> > +
> > +static __attribute__((unused)) inline
> > +void multi_arg_check(unsigned long ip, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f, __u64 *test_result)
> > +{
> > + if (ip == bpf_fentry_test[0]) {
> > + *test_result += (int) a == 1;
> > + } else if (ip == bpf_fentry_test[1]) {
> > + *test_result += (int) a == 2 && (__u64) b == 3;
> > + } else if (ip == bpf_fentry_test[2]) {
> > + *test_result += (char) a == 4 && (int) b == 5 && (__u64) c == 6;
> > + } else if (ip == bpf_fentry_test[3]) {
> > + *test_result += (void *) a == (void *) 7 && (char) b == 8 && (int) c == 9 && (__u64) d == 10;
> > + } else if (ip == bpf_fentry_test[4]) {
> > + *test_result += (__u64) a == 11 && (void *) b == (void *) 12 && (short) c == 13 && (int) d == 14 && (__u64) e == 15;
> > + } else if (ip == bpf_fentry_test[5]) {
> > + *test_result += (__u64) a == 16 && (void *) b == (void *) 17 && (short) c == 18 && (int) d == 19 && (void *) e == (void *) 20 && (__u64) f == 21;
> > + } else if (ip == bpf_fentry_test[6]) {
> > + *test_result += 1;
> > + } else if (ip == bpf_fentry_test[7]) {
> > + *test_result += 1;
> > + }
>
> why not use switch? and why the casting?
hum, for switch I'd need constants right?
casting is extra ;-) wanted to check the actual argument types,
but probably makes no sense
will check
>
> > +}
> > +
>
> [...]
>
> > diff --git a/tools/testing/selftests/bpf/progs/fentry_multi_test.c b/tools/testing/selftests/bpf/progs/fentry_multi_test.c
> > new file mode 100644
> > index 000000000000..a443fc958e5a
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/progs/fentry_multi_test.c
> > @@ -0,0 +1,18 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +#include <linux/bpf.h>
> > +#include <bpf/bpf_helpers.h>
> > +#include <bpf/bpf_tracing.h>
> > +#include "multi_check.h"
> > +
> > +char _license[] SEC("license") = "GPL";
> > +
> > +unsigned long long bpf_fentry_test[8];
> > +
> > +__u64 test_result = 0;
> > +
> > +SEC("fentry.multi/bpf_fentry_test*")
>
> wait, that's a regexp syntax that libc supports?.. Not .*? We should
> definitely not provide btf__find_by_pattern_kind() API, I'd like to
> avoid explaining what flavors of regexps libbpf supports.
ok
thanks,
jirka
