tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1
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 "trace-event.h"
14#include "machine.h"
15#include "util.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 */
24static struct trace_event tevent;
25static bool tevent_initialized;
26
27int trace_event__init(struct trace_event *t)
28{
29 struct pevent *pevent = pevent_alloc();
30
31 if (pevent) {
32 t->plugin_list = traceevent_load_plugins(pevent);
33 t->pevent = pevent;
34 }
35
36 return pevent ? 0 : -1;
37}
38
39static int trace_event__init2(void)
40{
41 int be = traceevent_host_bigendian();
42 struct pevent *pevent;
43
44 if (trace_event__init(&tevent))
45 return -1;
46
47 pevent = tevent.pevent;
48 pevent_set_flag(pevent, PEVENT_NSEC_OUTPUT);
49 pevent_set_file_bigendian(pevent, be);
50 pevent_set_host_bigendian(pevent, be);
51 tevent_initialized = true;
52 return 0;
53}
54
55int trace_event__register_resolver(struct machine *machine,
56 pevent_func_resolver_t *func)
57{
58 if (!tevent_initialized && trace_event__init2())
59 return -1;
60
61 return pevent_set_function_resolver(tevent.pevent, func, machine);
62}
63
64void trace_event__cleanup(struct trace_event *t)
65{
66 traceevent_unload_plugins(t->plugin_list, t->pevent);
67 pevent_free(t->pevent);
68}
69
70/*
71 * Returns pointer with encoded error via <linux/err.h> interface.
72 */
73static struct event_format*
74tp_format(const char *sys, const char *name)
75{
76 struct pevent *pevent = tevent.pevent;
77 struct event_format *event = NULL;
78 char path[PATH_MAX];
79 size_t size;
80 char *data;
81 int err;
82
83 scnprintf(path, PATH_MAX, "%s/%s/%s/format",
84 tracing_events_path, sys, name);
85
86 err = filename__read_str(path, &data, &size);
87 if (err)
88 return ERR_PTR(err);
89
90 pevent_parse_format(pevent, &event, data, size, sys);
91
92 free(data);
93 return event;
94}
95
96/*
97 * Returns pointer with encoded error via <linux/err.h> interface.
98 */
99struct event_format*
100trace_event__tp_format(const char *sys, const char *name)
101{
102 if (!tevent_initialized && trace_event__init2())
103 return ERR_PTR(-ENOMEM);
104
105 return tp_format(sys, name);
106}