From b822a139e3997a0a09da940e5c88ea505459e81f Mon Sep 17 00:00:00 2001 From: Hou Tao Date: Wed, 16 Nov 2022 15:23:48 +0800 Subject: [PATCH] libbpf: Use page size as max_entries when probing ring buffer map Using page size as max_entries when probing ring buffer map, else the probe may fail on host with 64KB page size (e.g., an ARM64 host). After the fix, the output of "bpftool feature" on above host will be correct. Before : eBPF map_type ringbuf is NOT available eBPF map_type user_ringbuf is NOT available After : eBPF map_type ringbuf is available eBPF map_type user_ringbuf is available Signed-off-by: Hou Tao Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20221116072351.1168938-2-houtao@huaweicloud.com --- src/libbpf_probes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/libbpf_probes.c b/src/libbpf_probes.c index ecaae29..393b5cd 100644 --- a/src/libbpf_probes.c +++ b/src/libbpf_probes.c @@ -243,7 +243,7 @@ bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex) case BPF_MAP_TYPE_RINGBUF: key_size = 0; value_size = 0; - max_entries = 4096; + max_entries = sysconf(_SC_PAGE_SIZE); break; case BPF_MAP_TYPE_UNSPEC: case BPF_MAP_TYPE_HASH: -- 2.33.0