1 // SPDX-License-Identifier: GPL-2.0
10 #include <linux/kernel.h>
11 #include <linux/err.h>
12 #include <traceevent/event-parse.h>
13 #include <api/fs/tracing_path.h>
14 #include <api/fs/fs.h>
15 #include "trace-event.h"
20 * global trace_event object used by trace_event__tp_format
22 * TODO There's no cleanup call for this. Add some sort of
23 * __exit function support and call trace_event__cleanup
26 static struct trace_event tevent;
27 static bool tevent_initialized;
29 int trace_event__init(struct trace_event *t)
31 struct pevent *pevent = pevent_alloc();
34 t->plugin_list = traceevent_load_plugins(pevent);
38 return pevent ? 0 : -1;
41 static int trace_event__init2(void)
43 int be = traceevent_host_bigendian();
44 struct pevent *pevent;
46 if (trace_event__init(&tevent))
49 pevent = tevent.pevent;
50 pevent_set_flag(pevent, PEVENT_NSEC_OUTPUT);
51 pevent_set_file_bigendian(pevent, be);
52 pevent_set_host_bigendian(pevent, be);
53 tevent_initialized = true;
57 int trace_event__register_resolver(struct machine *machine,
58 pevent_func_resolver_t *func)
60 if (!tevent_initialized && trace_event__init2())
63 return pevent_set_function_resolver(tevent.pevent, func, machine);
66 void trace_event__cleanup(struct trace_event *t)
68 traceevent_unload_plugins(t->plugin_list, t->pevent);
69 pevent_free(t->pevent);
73 * Returns pointer with encoded error via <linux/err.h> interface.
75 static struct event_format*
76 tp_format(const char *sys, const char *name)
78 struct pevent *pevent = tevent.pevent;
79 struct event_format *event = NULL;
85 scnprintf(path, PATH_MAX, "%s/%s/%s/format",
86 tracing_events_path, sys, name);
88 err = filename__read_str(path, &data, &size);
92 pevent_parse_format(pevent, &event, data, size, sys);
99 * Returns pointer with encoded error via <linux/err.h> interface.
102 trace_event__tp_format(const char *sys, const char *name)
104 if (!tevent_initialized && trace_event__init2())
105 return ERR_PTR(-ENOMEM);
107 return tp_format(sys, name);
110 struct event_format *trace_event__tp_format_id(int id)
112 if (!tevent_initialized && trace_event__init2())
113 return ERR_PTR(-ENOMEM);
115 return pevent_find_event(tevent.pevent, id);