diff options
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 9 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.h | 2 |
2 files changed, 8 insertions, 3 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index f6a071db5c6e..15737d7b5a28 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -216,9 +216,10 @@ static libbpf_print_fn_t __libbpf_pr = __base_pr; libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn) { - libbpf_print_fn_t old_print_fn = __libbpf_pr; + libbpf_print_fn_t old_print_fn; + + old_print_fn = __atomic_exchange_n(&__libbpf_pr, fn, __ATOMIC_RELAXED); - __libbpf_pr = fn; return old_print_fn; } @@ -227,8 +228,10 @@ void libbpf_print(enum libbpf_print_level level, const char *format, ...) { va_list args; int old_errno; + libbpf_print_fn_t print_fn; - if (!__libbpf_pr) + print_fn = __atomic_load_n(&__libbpf_pr, __ATOMIC_RELAXED); + if (!print_fn) return; old_errno = errno; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 1615e55e2e79..0b7362397ea3 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -101,6 +101,8 @@ typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level, * be used for libbpf warnings and informational messages. * @param fn The log print function. If NULL, libbpf won't print anything. * @return Pointer to old print function. + * + * This function is thread-safe. */ LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn); |