1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <stdio.h> |
3 | #include <unistd.h> |
4 | #include <stdlib.h> |
5 | #include <errno.h> |
6 | #include <sys/types.h> |
7 | #include <sys/stat.h> |
8 | #include <fcntl.h> |
9 | #include <linux/kernel.h> |
10 | #include <linux/err.h> |
11 | #include <traceevent/event-parse.h> |
12 | #include <api/fs/tracing_path.h> |
13 | #include <api/fs/fs.h> |
14 | #include "trace-event.h" |
15 | #include "machine.h" |
16 | |
17 | /* |
18 | * global trace_event object used by trace_event__tp_format |
19 | * |
20 | * TODO There's no cleanup call for this. Add some sort of |
21 | * __exit function support and call trace_event__cleanup |
22 | * there. |
23 | */ |
24 | static struct trace_event tevent; |
25 | static bool tevent_initialized; |
26 | |
27 | int trace_event__init(struct trace_event *t) |
28 | { |
29 | struct tep_handle *pevent = tep_alloc(); |
30 | |
31 | if (pevent) { |
32 | t->plugin_list = tep_load_plugins(pevent); |
33 | t->pevent = pevent; |
34 | } |
35 | |
36 | return pevent ? 0 : -1; |
37 | } |
38 | |
39 | static int trace_event__init2(void) |
40 | { |
41 | int be = tep_is_bigendian(); |
42 | struct tep_handle *pevent; |
43 | |
44 | if (trace_event__init(t: &tevent)) |
45 | return -1; |
46 | |
47 | pevent = tevent.pevent; |
48 | tep_set_flag(pevent, TEP_NSEC_OUTPUT); |
49 | tep_set_file_bigendian(pevent, be); |
50 | tep_set_local_bigendian(pevent, be); |
51 | tevent_initialized = true; |
52 | return 0; |
53 | } |
54 | |
55 | int trace_event__register_resolver(struct machine *machine, |
56 | tep_func_resolver_t *func) |
57 | { |
58 | if (!tevent_initialized && trace_event__init2()) |
59 | return -1; |
60 | |
61 | return tep_set_function_resolver(tevent.pevent, func, machine); |
62 | } |
63 | |
64 | void trace_event__cleanup(struct trace_event *t) |
65 | { |
66 | tep_unload_plugins(t->plugin_list, t->pevent); |
67 | tep_free(t->pevent); |
68 | } |
69 | |
70 | /* |
71 | * Returns pointer with encoded error via <linux/err.h> interface. |
72 | */ |
73 | static struct tep_event* |
74 | tp_format(const char *sys, const char *name) |
75 | { |
76 | char *tp_dir = get_events_file(sys); |
77 | struct tep_handle *pevent = tevent.pevent; |
78 | struct tep_event *event = NULL; |
79 | char path[PATH_MAX]; |
80 | size_t size; |
81 | char *data; |
82 | int err; |
83 | |
84 | if (!tp_dir) |
85 | return ERR_PTR(error: -errno); |
86 | |
87 | scnprintf(buf: path, PATH_MAX, fmt: "%s/%s/format" , tp_dir, name); |
88 | put_events_file(tp_dir); |
89 | |
90 | err = filename__read_str(path, &data, &size); |
91 | if (err) |
92 | return ERR_PTR(error: err); |
93 | |
94 | tep_parse_format(pevent, &event, data, size, sys); |
95 | |
96 | free(data); |
97 | return event; |
98 | } |
99 | |
100 | /* |
101 | * Returns pointer with encoded error via <linux/err.h> interface. |
102 | */ |
103 | struct tep_event* |
104 | trace_event__tp_format(const char *sys, const char *name) |
105 | { |
106 | if (!tevent_initialized && trace_event__init2()) |
107 | return ERR_PTR(error: -ENOMEM); |
108 | |
109 | return tp_format(sys, name); |
110 | } |
111 | |
112 | struct tep_event *trace_event__tp_format_id(int id) |
113 | { |
114 | if (!tevent_initialized && trace_event__init2()) |
115 | return ERR_PTR(error: -ENOMEM); |
116 | |
117 | return tep_find_event(tevent.pevent, id); |
118 | } |
119 | |