On 2017/2/8 4:56, Mickaël Salaün wrote:
Do not call a second time bpf(2) when a program load failed.
BPF_PROG_LOAD should success most of the time. Setting log_level to 0 by default and require log buffer when failure can make it faster in normal case. Thank you.
Signed-off-by: Mickaël Salaün <m...@digikod.net> Cc: Alexei Starovoitov <a...@fb.com> Cc: Arnaldo Carvalho de Melo <a...@redhat.com> Cc: Daniel Borkmann <dan...@iogearbox.net> Cc: Wang Nan <wangn...@huawei.com> --- tools/lib/bpf/bpf.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 3ddb58a36d3c..fda3f494f1cd 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -73,7 +73,6 @@ int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns, size_t insns_cnt, char *license, __u32 kern_version, char *log_buf, size_t log_buf_sz) { - int fd; union bpf_attr attr;bzero(&attr, sizeof(attr));@@ -81,20 +80,15 @@ int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns, attr.insn_cnt = (__u32)insns_cnt; attr.insns = ptr_to_u64(insns); attr.license = ptr_to_u64(license); - attr.log_buf = ptr_to_u64(NULL); - attr.log_size = 0; - attr.log_level = 0; + attr.log_buf = ptr_to_u64(log_buf); + attr.log_size = log_buf_sz; attr.kern_version = kern_version;- fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));- if (fd >= 0 || !log_buf || !log_buf_sz) - return fd; + if (log_buf && log_buf_sz > 0) { + attr.log_level = 1; + log_buf[0] = 0; + }- /* Try again with log */- attr.log_buf = ptr_to_u64(log_buf); - attr.log_size = log_buf_sz; - attr.log_level = 1; - log_buf[0] = 0; return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); }
