shorten disksnoop.c example further

examples/disksnoop.c

@@ -15,27 +15,21 @@
 
 BPF_HASH(start, struct request *);
 
-int kprobe__blk_start_request(struct pt_regs *ctx, struct request *req) {
-	u64 ts;
-
+void kprobe__blk_start_request(struct pt_regs *ctx, struct request *req) {
 	// stash start timestamp by request ptr
-	ts = bpf_ktime_get_ns();
-	start.update(&req, &ts);
+	u64 ts = bpf_ktime_get_ns();
 
-	return 0;
+	start.update(&req, &ts);
 }
 
-int kprobe__blk_update_request(struct pt_regs *ctx, struct request *req) {
+void kprobe__blk_update_request(struct pt_regs *ctx, struct request *req) {
 	u64 *tsp, delta;
 
 	tsp = start.lookup(&req);
-
 	if (tsp != 0) {
 		delta = bpf_ktime_get_ns() - *tsp;
 		bpf_trace_printk("%d %x %d\n", req->__data_len,
 		    req->cmd_flags, delta / 1000);
 		start.delete(&req);
 	}
-
-	return 0;
 }