xref: /aosp_15_r20/external/bcc/libbpf-tools/mdflush.bpf.c (revision 387f9dfdfa2baef462e92476d413c7bc2470293e)
1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 /* Copyright (c) 2021~2022 Hengqi Chen */
3 #include <vmlinux.h>
4 #include <bpf/bpf_tracing.h>
5 #include <bpf/bpf_helpers.h>
6 #include <bpf/bpf_core_read.h>
7 #include "core_fixes.bpf.h"
8 #include "mdflush.h"
9 
10 struct {
11 	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
12 	__type(key, __u32);
13 	__type(value, __u32);
14 } events SEC(".maps");
15 
16 SEC("fentry/md_flush_request")
BPF_PROG(md_flush_request,void * mddev,void * bio)17 int BPF_PROG(md_flush_request, void *mddev, void *bio)
18 {
19 	__u64 pid = bpf_get_current_pid_tgid() >> 32;
20 	struct event event = {};
21 	struct gendisk *gendisk;
22 
23 	event.pid = pid;
24 	gendisk = get_gendisk(bio);
25 	BPF_CORE_READ_STR_INTO(event.disk, gendisk, disk_name);
26 	bpf_get_current_comm(event.comm, sizeof(event.comm));
27 	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, &event, sizeof(event));
28 	return 0;
29 }
30 
31 SEC("kprobe/md_flush_request")
BPF_KPROBE(kprobe_md_flush_request,void * mddev,void * bio)32 int BPF_KPROBE(kprobe_md_flush_request, void *mddev, void *bio)
33 {
34 	__u64 pid = bpf_get_current_pid_tgid() >> 32;
35 	struct event event = {};
36 	struct gendisk *gendisk;
37 
38 	event.pid = pid;
39 	gendisk = get_gendisk(bio);
40 	BPF_CORE_READ_STR_INTO(event.disk, gendisk, disk_name);
41 	bpf_get_current_comm(event.comm, sizeof(event.comm));
42 	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, &event, sizeof(event));
43 	return 0;
44 }
45 
46 char LICENSE[] SEC("license") = "Dual BSD/GPL";
47