Reimplement bpf_probe_large_insn_limit() in bpftool, as that libbpf API
is scheduled for deprecation in v0.8.
Acked-by: Dave Marchevsky <davemarchevsky@xxxxxx>
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
---
tools/bpf/bpftool/feature.c | 26 +++++++++++++++++++++++---
1 file changed, 23 insertions(+), 3 deletions(-)
diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c
index 5397077d0d9e..6719b9282eca 100644
--- a/tools/bpf/bpftool/feature.c
+++ b/tools/bpf/bpftool/feature.c
@@ -642,12 +642,32 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type,
printf("\n");
}
-static void
-probe_large_insn_limit(const char *define_prefix, __u32 ifindex)
+/*
+ * Probe for availability of kernel commit (5.3):
+ *
+ * c04c0d2b968a ("bpf: increase complexity limit and maximum program size")
+ */
+static void probe_large_insn_limit(const char *define_prefix, __u32 ifindex)
{
+ LIBBPF_OPTS(bpf_prog_load_opts, opts,
+ .prog_ifindex = ifindex,
+ );
+ struct bpf_insn insns[BPF_MAXINSNS + 1];
bool res;
+ int i, fd;
+
+ for (i = 0; i < BPF_MAXINSNS; i++)
+ insns[i] = BPF_MOV64_IMM(BPF_REG_0, 1);
+ insns[BPF_MAXINSNS] = BPF_EXIT_INSN();
+
+ errno = 0;
+ fd = bpf_prog_load(BPF_PROG_TYPE_SCHED_CLS, NULL, "GPL",
+ insns, ARRAY_SIZE(insns), &opts);
+ res = fd >= 0 || (errno != E2BIG && errno != EINVAL);
+
+ if (fd >= 0)
+ close(fd);
- res = bpf_probe_large_insn_limit(ifindex);
print_bool_feature("have_large_insn_limit",
"Large program size limit",
"LARGE_INSN_LIMIT",
--
2.30.2
