Hi, On 11/12/2022 1:47 AM, sdf@xxxxxxxxxx wrote: > On 11/11, Hou Tao wrote: >> From: Hou Tao <houtao1@xxxxxxxxxx> > >> Adjusting the size of ring buffer 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 <houtao1@xxxxxxxxxx> >> --- >> tools/lib/bpf/libbpf.c | 2 +- >> tools/lib/bpf/libbpf_internal.h | 2 ++ >> tools/lib/bpf/libbpf_probes.c | 2 +- >> 3 files changed, 4 insertions(+), 2 deletions(-) SNIP > >> #endif /* __LIBBPF_LIBBPF_INTERNAL_H */ >> diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c >> index f3a8e8e74eb8..29a1db2645fd 100644 >> --- a/tools/lib/bpf/libbpf_probes.c >> +++ b/tools/lib/bpf/libbpf_probes.c >> @@ -234,7 +234,7 @@ static int probe_map_create(enum bpf_map_type map_type) >> case BPF_MAP_TYPE_USER_RINGBUF: >> key_size = 0; >> value_size = 0; >> - max_entries = 4096; >> + max_entries = adjust_ringbuf_sz(4096); > > Why not pass PAGE_SIZE directly here? Something like: > > max_entries = sysconf(_SC_PAGE_SIZE); > > ? Good idea. Will do that in v2. > >> break; >> case BPF_MAP_TYPE_STRUCT_OPS: >> /* we'll get -ENOTSUPP for invalid BTF type ID for struct_ops */ >> -- >> 2.29.2
