Re: [PATCHv4 bpf-next 24/25] selftests/bpf: Add tracing multi attach benchmark test
On Wed, Mar 25, 2026 at 02:45:31PM +0800, Leon Hwang wrote:
SNIP
> > +
> > + attach_delta = (attach_end_ns - attach_start_ns) / 10.0;
> > + detach_delta = (detach_end_ns - detach_start_ns) / 10.0;
> > +
> > + printf("%s: found %lu functions\n", __func__, cnt);
> > + printf("%s: attached in %7.3lfs\n", __func__, attach_delta);
> > + printf("%s: detached in %7.3lfs\n", __func__, detach_delta);
> > +
> > +cleanup:
> > + tracing_multi_bench__destroy(skel);
> > + tdestroy(root, tdestroy_free_nop);
> > + free_kallsyms_local(ksyms);
> > + free(ids);
>
> Is btf__free(btf) missing here? Since 'btf' was calloc inner
> btf__load_vmlinux_btf().
ah yea, will add, thanks
jirka
Re: [PATCHv4 bpf-next 24/25] selftests/bpf: Add tracing multi attach benchmark test
On Wed, Mar 25, 2026 at 08:11:00AM -0700, Alexei Starovoitov wrote:
SNIP
> > > + attach_start_ns = get_time_ns();
> > > + link = bpf_program__attach_tracing_multi(skel->progs.bench, NULL,
> > > &opts);
> > > + attach_end_ns = get_time_ns();
> > > +
> > > + if (!ASSERT_OK_PTR(link, "bpf_program__attach_tracing_multi"))
> > > + goto cleanup;
> > > +
> > > + detach_start_ns = get_time_ns();
> > > + bpf_link__destroy(link);
> > > + detach_end_ns = get_time_ns();
> > > +
> > > + attach_delta = (attach_end_ns - attach_start_ns) / 10.0;
> > > + detach_delta = (detach_end_ns - detach_start_ns) / 10.0;
> > > +
> > > + printf("%s: found %lu functions\n", __func__, cnt);
> > > + printf("%s: attached in %7.3lfs\n", __func__, attach_delta);
> > > + printf("%s: detached in %7.3lfs\n", __func__, detach_delta);
> > > +
> > > +cleanup:
> > > + tracing_multi_bench__destroy(skel);
> > > + tdestroy(root, tdestroy_free_nop);
> > > + free_kallsyms_local(ksyms);
> > > + free(ids);
> >
> > Is btf__free(btf) missing here? Since 'btf' was calloc inner
> > btf__load_vmlinux_btf().
>
> Good point.
> Leon, please trim your replies. No need to quote the whole patch.
>
> btw sashiko caught it too:
> https://sashiko.dev/#/patchset/20260324081846.2334094-1-jolsa%40kernel.org
> and many other bugs beyond what bpf CI could find.
>
> Jiri, please address them all.
ok, will check
jirka
Re: [PATCHv4 bpf-next 24/25] selftests/bpf: Add tracing multi attach benchmark test
On Tue, Mar 24, 2026 at 11:45 PM Leon Hwang wrote:
>
> > +
> > + btf = btf__load_vmlinux_btf();
> > + if (!ASSERT_OK_PTR(btf, "btf__load_vmlinux_btf"))
> > + return;> +
> > + skel = tracing_multi_bench__open_and_load();
> > + if (!ASSERT_OK_PTR(skel, "tracing_multi_bench__open_and_load"))
> > + goto cleanup;
> > +
> > + if (!ASSERT_OK(bpf_get_ksyms(&ksyms, true), "get_syms"))
> > + goto cleanup;
> > +
> > + /* Get all ftrace 'safe' symbols.. */
> > + for (i = 0; i < ksyms->filtered_cnt; i++) {
> > + if (is_unsafe_function(ksyms->filtered_syms[i]))
> > + continue;
> > + tsearch(&ksyms->filtered_syms[i], &root, compare);
> > + }
> > +
> > + /* ..and filter them through BTF and btf_type_is_traceable_func. */
> > + nr = btf__type_cnt(btf);
> > + for (type_id = 1; type_id < nr; type_id++) {
> > + const struct btf_type *type;
> > + const char *str;
> > +
> > + type = btf__type_by_id(btf, type_id);
> > + if (!type)
> > + break;
> > +
> > + if (BTF_INFO_KIND(type->info) != BTF_KIND_FUNC)
> > + continue;
> > +
> > + str = btf__name_by_offset(btf, type->name_off);
> > + if (!str)
> > + break;
> > +
> > + if (!tfind(&str, &root, compare))
> > + continue;
> > +
> > + if (!btf_type_is_traceable_func(btf, type))
> > + continue;
> > +
> > + err = libbpf_ensure_mem((void **) &ids, &cap, sizeof(*ids),
> > cnt + 1);
> > + if (err)
> > + goto cleanup;
> > +
> > + ids[cnt++] = type_id;
> > + }
> > +
> > + opts.ids = ids;
> > + opts.cnt = cnt;
> > +
> > + attach_start_ns = get_time_ns();
> > + link = bpf_program__attach_tracing_multi(skel->progs.bench, NULL,
> > &opts);
> > + attach_end_ns = get_time_ns();
> > +
> > + if (!ASSERT_OK_PTR(link, "bpf_program__attach_tracing_multi"))
> > + goto cleanup;
> > +
> > + detach_start_ns = get_time_ns();
> > + bpf_link__destroy(link);
> > + detach_end_ns = get_time_ns();
> > +
> > + attach_delta = (attach_end_ns - attach_start_ns) / 10.0;
> > + detach_delta = (detach_end_ns - detach_start_ns) / 10.0;
> > +
> > + printf("%s: found %lu functions\n", __func__, cnt);
> > + printf("%s: attached in %7.3lfs\n", __func__, attach_delta);
> > + printf("%s: detached in %7.3lfs\n", __func__, detach_delta);
> > +
> > +cleanup:
> > + tracing_multi_bench__destroy(skel);
> > + tdestroy(root, tdestroy_free_nop);
> > + free_kallsyms_local(ksyms);
> > + free(ids);
>
> Is btf__free(btf) missing here? Since 'btf' was calloc inner
> btf__load_vmlinux_btf().
Good point.
Leon, please trim your replies. No need to quote the whole patch.
btw sashiko caught it too:
https://sashiko.dev/#/patchset/20260324081846.2334094-1-jolsa%40kernel.org
and many other bugs beyond what bpf CI could find.
Jiri, please address them all.
Re: [PATCHv4 bpf-next 24/25] selftests/bpf: Add tracing multi attach benchmark test
On 24/3/26 16:18, Jiri Olsa wrote:
> Adding benchmark test that attaches to (almost) all allowed tracing
> functions and display attach/detach times.
>
> # ./test_progs -t tracing_multi_bench_attach -v
> bpf_testmod.ko is already unloaded.
> Loading bpf_testmod.ko...
> Successfully loaded bpf_testmod.ko.
> serial_test_tracing_multi_bench_attach:PASS:btf__load_vmlinux_btf 0 nsec
>
> serial_test_tracing_multi_bench_attach:PASS:tracing_multi_bench__open_and_load
> 0 nsec
> serial_test_tracing_multi_bench_attach:PASS:get_syms 0 nsec
>
> serial_test_tracing_multi_bench_attach:PASS:bpf_program__attach_tracing_multi
> 0 nsec
> serial_test_tracing_multi_bench_attach: found 51186 functions
> serial_test_tracing_multi_bench_attach: attached in 1.295s
> serial_test_tracing_multi_bench_attach: detached in 0.243s
> #507 tracing_multi_bench_attach:OK
> Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
> Successfully unloaded bpf_testmod.ko.
>
> Exporting skip_entry as is_unsafe_function and using it in the test.
>
> Signed-off-by: Jiri Olsa
> ---
> .../selftests/bpf/prog_tests/tracing_multi.c | 98 +++
> .../selftests/bpf/progs/tracing_multi_bench.c | 12 +++
> tools/testing/selftests/bpf/trace_helpers.c | 6 +-
> tools/testing/selftests/bpf/trace_helpers.h | 1 +
> 4 files changed, 114 insertions(+), 3 deletions(-)
> create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_bench.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
> b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
> index dece45d8fb5e..6917471e329c 100644
> --- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
> +++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
> @@ -9,6 +9,7 @@
> #include "tracing_multi_intersect.skel.h"
> #include "tracing_multi_session.skel.h"
> #include "tracing_multi_fail.skel.h"
> +#include "tracing_multi_bench.skel.h"
> #include "trace_helpers.h"
>
> static __u64 bpf_fentry_test_cookies[] = {
> @@ -571,6 +572,103 @@ static void test_attach_api_fails(void)
> free(ids2);
> }
>
> +void serial_test_tracing_multi_bench_attach(void)
> +{
> + LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
> + struct tracing_multi_bench *skel = NULL;
> + long attach_start_ns, attach_end_ns;
> + long detach_start_ns, detach_end_ns;
> + double attach_delta, detach_delta;
> + struct bpf_link *link = NULL;
> + size_t i, cap = 0, cnt = 0;
> + struct ksyms *ksyms = NULL;
> + void *root = NULL;
> + __u32 *ids = NULL;
> + __u32 nr, type_id;
> + struct btf *btf;
> + int err;
> +
> +#ifndef __x86_64__
> + test__skip();
> + return;
> +#endif
> +
> + btf = btf__load_vmlinux_btf();
> + if (!ASSERT_OK_PTR(btf, "btf__load_vmlinux_btf"))
> + return;> +
> + skel = tracing_multi_bench__open_and_load();
> + if (!ASSERT_OK_PTR(skel, "tracing_multi_bench__open_and_load"))
> + goto cleanup;
> +
> + if (!ASSERT_OK(bpf_get_ksyms(&ksyms, true), "get_syms"))
> + goto cleanup;
> +
> + /* Get all ftrace 'safe' symbols.. */
> + for (i = 0; i < ksyms->filtered_cnt; i++) {
> + if (is_unsafe_function(ksyms->filtered_syms[i]))
> + continue;
> + tsearch(&ksyms->filtered_syms[i], &root, compare);
> + }
> +
> + /* ..and filter them through BTF and btf_type_is_traceable_func. */
> + nr = btf__type_cnt(btf);
> + for (type_id = 1; type_id < nr; type_id++) {
> + const struct btf_type *type;
> + const char *str;
> +
> + type = btf__type_by_id(btf, type_id);
> + if (!type)
> + break;
> +
> + if (BTF_INFO_KIND(type->info) != BTF_KIND_FUNC)
> + continue;
> +
> + str = btf__name_by_offset(btf, type->name_off);
> + if (!str)
> + break;
> +
> + if (!tfind(&str, &root, compare))
> + continue;
> +
> + if (!btf_type_is_traceable_func(btf, type))
> + continue;
> +
> + err = libbpf_ensure_mem((void **) &ids, &cap, sizeof(*ids), cnt
> + 1);
> + if (err)
> + goto cleanup;
> +
> + ids[cnt++] = type_id;
> + }
> +
> + opts.ids = ids;
> + opts.cnt = cnt;
> +
> + attach_start_ns = get_time_ns();
> + link = bpf_program__attach_tracing_multi(skel->progs.bench, NULL,
> &opts);
> + attach_end_ns = get_time_ns();
> +
> + if (!ASSERT_OK_PTR(link, "bpf_program__attach_tracing_multi"))
> + goto cleanup;
> +
> + detach_start_ns = get_time_ns();
> + bpf_link__destroy(link);
> + detach_end_ns = get_time_ns();
> +
> + attach_delta = (attach_end_ns - attach_start_ns) / 10.0;
> + detach_delta = (detach_end_ns - detach_start_ns) / 10.0;
> +
> + printf("%s: found %lu functions\n
[PATCHv4 bpf-next 24/25] selftests/bpf: Add tracing multi attach benchmark test
Adding benchmark test that attaches to (almost) all allowed tracing
functions and display attach/detach times.
# ./test_progs -t tracing_multi_bench_attach -v
bpf_testmod.ko is already unloaded.
Loading bpf_testmod.ko...
Successfully loaded bpf_testmod.ko.
serial_test_tracing_multi_bench_attach:PASS:btf__load_vmlinux_btf 0 nsec
serial_test_tracing_multi_bench_attach:PASS:tracing_multi_bench__open_and_load
0 nsec
serial_test_tracing_multi_bench_attach:PASS:get_syms 0 nsec
serial_test_tracing_multi_bench_attach:PASS:bpf_program__attach_tracing_multi
0 nsec
serial_test_tracing_multi_bench_attach: found 51186 functions
serial_test_tracing_multi_bench_attach: attached in 1.295s
serial_test_tracing_multi_bench_attach: detached in 0.243s
#507 tracing_multi_bench_attach:OK
Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
Successfully unloaded bpf_testmod.ko.
Exporting skip_entry as is_unsafe_function and using it in the test.
Signed-off-by: Jiri Olsa
---
.../selftests/bpf/prog_tests/tracing_multi.c | 98 +++
.../selftests/bpf/progs/tracing_multi_bench.c | 12 +++
tools/testing/selftests/bpf/trace_helpers.c | 6 +-
tools/testing/selftests/bpf/trace_helpers.h | 1 +
4 files changed, 114 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_bench.c
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index dece45d8fb5e..6917471e329c 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -9,6 +9,7 @@
#include "tracing_multi_intersect.skel.h"
#include "tracing_multi_session.skel.h"
#include "tracing_multi_fail.skel.h"
+#include "tracing_multi_bench.skel.h"
#include "trace_helpers.h"
static __u64 bpf_fentry_test_cookies[] = {
@@ -571,6 +572,103 @@ static void test_attach_api_fails(void)
free(ids2);
}
+void serial_test_tracing_multi_bench_attach(void)
+{
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ struct tracing_multi_bench *skel = NULL;
+ long attach_start_ns, attach_end_ns;
+ long detach_start_ns, detach_end_ns;
+ double attach_delta, detach_delta;
+ struct bpf_link *link = NULL;
+ size_t i, cap = 0, cnt = 0;
+ struct ksyms *ksyms = NULL;
+ void *root = NULL;
+ __u32 *ids = NULL;
+ __u32 nr, type_id;
+ struct btf *btf;
+ int err;
+
+#ifndef __x86_64__
+ test__skip();
+ return;
+#endif
+
+ btf = btf__load_vmlinux_btf();
+ if (!ASSERT_OK_PTR(btf, "btf__load_vmlinux_btf"))
+ return;
+
+ skel = tracing_multi_bench__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_bench__open_and_load"))
+ goto cleanup;
+
+ if (!ASSERT_OK(bpf_get_ksyms(&ksyms, true), "get_syms"))
+ goto cleanup;
+
+ /* Get all ftrace 'safe' symbols.. */
+ for (i = 0; i < ksyms->filtered_cnt; i++) {
+ if (is_unsafe_function(ksyms->filtered_syms[i]))
+ continue;
+ tsearch(&ksyms->filtered_syms[i], &root, compare);
+ }
+
+ /* ..and filter them through BTF and btf_type_is_traceable_func. */
+ nr = btf__type_cnt(btf);
+ for (type_id = 1; type_id < nr; type_id++) {
+ const struct btf_type *type;
+ const char *str;
+
+ type = btf__type_by_id(btf, type_id);
+ if (!type)
+ break;
+
+ if (BTF_INFO_KIND(type->info) != BTF_KIND_FUNC)
+ continue;
+
+ str = btf__name_by_offset(btf, type->name_off);
+ if (!str)
+ break;
+
+ if (!tfind(&str, &root, compare))
+ continue;
+
+ if (!btf_type_is_traceable_func(btf, type))
+ continue;
+
+ err = libbpf_ensure_mem((void **) &ids, &cap, sizeof(*ids), cnt
+ 1);
+ if (err)
+ goto cleanup;
+
+ ids[cnt++] = type_id;
+ }
+
+ opts.ids = ids;
+ opts.cnt = cnt;
+
+ attach_start_ns = get_time_ns();
+ link = bpf_program__attach_tracing_multi(skel->progs.bench, NULL,
&opts);
+ attach_end_ns = get_time_ns();
+
+ if (!ASSERT_OK_PTR(link, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ detach_start_ns = get_time_ns();
+ bpf_link__destroy(link);
+ detach_end_ns = get_time_ns();
+
+ attach_delta = (attach_end_ns - attach_start_ns) / 10.0;
+ detach_delta = (detach_end_ns - detach_start_ns) / 10.0;
+
+ printf("%s: found %lu functions\n", __func__, cnt);
+ printf("%s: attached in %7.3lfs\n", __func__, attach_delta);
+ printf("%s: detached in %7.3lfs\n", __func__, detach_delta);
+
+cleanup:
+ tracin
