From 51a33c60f1c22c0d2dafad774315ba1537765442 Mon Sep 17 00:00:00 2001 From: Qiang Wang Date: Mon, 27 Dec 2021 21:07:13 +0800 Subject: libbpf: Support repeated legacy kprobes on same function If repeated legacy kprobes on same function in one process, libbpf will register using the same probe name and got -EBUSY error. So append index to the probe name format to fix this problem. Co-developed-by: Chengming Zhou Signed-off-by: Qiang Wang Signed-off-by: Chengming Zhou Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211227130713.66933-2-wangqiang.wq.frank@bytedance.com --- tools/lib/bpf/libbpf.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 26e49e6aa5b1..7f10dd501a52 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -9916,7 +9916,10 @@ static int append_to_file(const char *file, const char *fmt, ...) static void gen_kprobe_legacy_event_name(char *buf, size_t buf_sz, const char *kfunc_name, size_t offset) { - snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx", getpid(), kfunc_name, offset); + static int index = 0; + + snprintf(buf, buf_sz, "libbpf_%u_%s_0x%zx_%d", getpid(), kfunc_name, offset, + __sync_fetch_and_add(&index, 1)); } static int add_kprobe_event_legacy(const char *probe_name, bool retprobe, -- cgit v1.2.3-59-g8ed1b