1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright (C) 2018 Facebook
3 // Author: Yonghong Song <yhs@fb.com>
12 #include <sys/types.h>
20 /* 0: undecided, 1: supported, 2: not supported */
21 static int perf_query_supported;
22 static bool has_perf_query_support(void)
24 __u64 probe_offset, probe_addr;
25 __u32 len, prog_id, fd_type;
29 if (perf_query_supported)
32 fd = open("/", O_RDONLY);
34 p_err("perf_query_support: cannot open directory \"/\" (%s)",
39 /* the following query will fail as no bpf attachment,
40 * the expected errno is ENOTSUPP
44 bpf_task_fd_query(getpid(), fd, 0, buf, &len, &prog_id,
45 &fd_type, &probe_offset, &probe_addr);
47 if (errno == 524 /* ENOTSUPP */) {
48 perf_query_supported = 1;
52 perf_query_supported = 2;
53 p_err("perf_query_support: %s", strerror(errno));
55 "HINT: non root or kernel doesn't support TASK_FD_QUERY\n");
60 return perf_query_supported == 1;
63 static void print_perf_json(int pid, int fd, __u32 prog_id, __u32 fd_type,
64 char *buf, __u64 probe_offset, __u64 probe_addr)
66 jsonw_start_object(json_wtr);
67 jsonw_int_field(json_wtr, "pid", pid);
68 jsonw_int_field(json_wtr, "fd", fd);
69 jsonw_uint_field(json_wtr, "prog_id", prog_id);
71 case BPF_FD_TYPE_RAW_TRACEPOINT:
72 jsonw_string_field(json_wtr, "fd_type", "raw_tracepoint");
73 jsonw_string_field(json_wtr, "tracepoint", buf);
75 case BPF_FD_TYPE_TRACEPOINT:
76 jsonw_string_field(json_wtr, "fd_type", "tracepoint");
77 jsonw_string_field(json_wtr, "tracepoint", buf);
79 case BPF_FD_TYPE_KPROBE:
80 jsonw_string_field(json_wtr, "fd_type", "kprobe");
82 jsonw_string_field(json_wtr, "func", buf);
83 jsonw_lluint_field(json_wtr, "offset", probe_offset);
85 jsonw_lluint_field(json_wtr, "addr", probe_addr);
88 case BPF_FD_TYPE_KRETPROBE:
89 jsonw_string_field(json_wtr, "fd_type", "kretprobe");
91 jsonw_string_field(json_wtr, "func", buf);
92 jsonw_lluint_field(json_wtr, "offset", probe_offset);
94 jsonw_lluint_field(json_wtr, "addr", probe_addr);
97 case BPF_FD_TYPE_UPROBE:
98 jsonw_string_field(json_wtr, "fd_type", "uprobe");
99 jsonw_string_field(json_wtr, "filename", buf);
100 jsonw_lluint_field(json_wtr, "offset", probe_offset);
102 case BPF_FD_TYPE_URETPROBE:
103 jsonw_string_field(json_wtr, "fd_type", "uretprobe");
104 jsonw_string_field(json_wtr, "filename", buf);
105 jsonw_lluint_field(json_wtr, "offset", probe_offset);
108 jsonw_end_object(json_wtr);
111 static void print_perf_plain(int pid, int fd, __u32 prog_id, __u32 fd_type,
112 char *buf, __u64 probe_offset, __u64 probe_addr)
114 printf("pid %d fd %d: prog_id %u ", pid, fd, prog_id);
116 case BPF_FD_TYPE_RAW_TRACEPOINT:
117 printf("raw_tracepoint %s\n", buf);
119 case BPF_FD_TYPE_TRACEPOINT:
120 printf("tracepoint %s\n", buf);
122 case BPF_FD_TYPE_KPROBE:
124 printf("kprobe func %s offset %llu\n", buf,
127 printf("kprobe addr %llu\n", probe_addr);
129 case BPF_FD_TYPE_KRETPROBE:
131 printf("kretprobe func %s offset %llu\n", buf,
134 printf("kretprobe addr %llu\n", probe_addr);
136 case BPF_FD_TYPE_UPROBE:
137 printf("uprobe filename %s offset %llu\n", buf, probe_offset);
139 case BPF_FD_TYPE_URETPROBE:
140 printf("uretprobe filename %s offset %llu\n", buf,
146 static int show_proc(const char *fpath, const struct stat *sb,
147 int tflag, struct FTW *ftwbuf)
149 __u64 probe_offset, probe_addr;
150 __u32 len, prog_id, fd_type;
151 int err, pid = 0, fd = 0;
155 /* prefix always /proc */
160 /* pid should be all numbers */
162 while (isdigit(*pch)) {
163 pid = pid * 10 + *pch - '0';
169 return FTW_SKIP_SUBTREE;
171 /* check /proc/<pid>/fd directory */
173 if (strncmp(pch, "fd", 2))
174 return FTW_SKIP_SUBTREE;
179 return FTW_SKIP_SUBTREE;
181 /* check /proc/<pid>/fd/<fd_num> */
183 while (isdigit(*pch)) {
184 fd = fd * 10 + *pch - '0';
188 return FTW_SKIP_SUBTREE;
190 /* query (pid, fd) for potential perf events */
192 err = bpf_task_fd_query(pid, fd, 0, buf, &len, &prog_id, &fd_type,
193 &probe_offset, &probe_addr);
198 print_perf_json(pid, fd, prog_id, fd_type, buf, probe_offset,
201 print_perf_plain(pid, fd, prog_id, fd_type, buf, probe_offset,
207 static int do_show(int argc, char **argv)
209 int flags = FTW_ACTIONRETVAL | FTW_PHYS;
210 int err = 0, nopenfd = 16;
212 if (!has_perf_query_support())
216 jsonw_start_array(json_wtr);
217 if (nftw("/proc", show_proc, nopenfd, flags) == -1) {
218 p_err("%s", strerror(errno));
222 jsonw_end_array(json_wtr);
227 static int do_help(int argc, char **argv)
230 "Usage: %s %s { show | list | help }\n"
237 static const struct cmd cmds[] = {
244 int do_perf(int argc, char **argv)
246 return cmd_select(cmds, argc, argv, do_help);