[PATCH bpf-next v2 2/2] bpftool: Probe for bounded loop support
From: Paul Chaignon <hidden>
Date: 2021-12-17 13:52:43
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [tooling] (bpftool), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Quentin Monnet, Linus Torvalds
This patch probes for bounded loop support and displays the results as
part of the miscellaneous section, as shown below.
$ bpftool feature probe | grep loops
Bounded loop support is available
$ bpftool feature probe macro | grep LOOPS
#define HAVE_BOUNDED_LOOPS
$ bpftool feature probe -j | jq .misc
{
"have_large_insn_limit": true,
"have_bounded_loops": true
}
Reviewed-by: Quentin Monnet <redacted>
Signed-off-by: Paul Chaignon <redacted>
---
Changes in v2:
- Resending to fix a format error.
tools/bpf/bpftool/feature.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c
index 5397077d0d9e..7aee920162e5 100644
--- a/tools/bpf/bpftool/feature.c
+++ b/tools/bpf/bpftool/feature.c@@ -654,6 +654,18 @@ probe_large_insn_limit(const char *define_prefix, __u32 ifindex) res, define_prefix); } +static void +probe_bounded_loops(const char *define_prefix, __u32 ifindex) +{ + bool res; + + res = bpf_probe_bounded_loops(ifindex); + print_bool_feature("have_bounded_loops", + "Bounded loop support", + "BOUNDED_LOOPS", + res, define_prefix); +} + static void section_system_config(enum probe_component target, const char *define_prefix) {
@@ -768,6 +780,7 @@ static void section_misc(const char *define_prefix, __u32 ifindex) "/*** eBPF misc features ***/", define_prefix); probe_large_insn_limit(define_prefix, ifindex); + probe_bounded_loops(define_prefix, ifindex); print_end_section(); }
--
2.25.1