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 <api/fs/fs.h> 14 #include "trace-event.h" 15 #include "machine.h" 16 #include "util.h" 17 18 /* 19 * global trace_event object used by trace_event__tp_format 20 * 21 * TODO There's no cleanup call for this. Add some sort of 22 * __exit function support and call trace_event__cleanup 23 * there. 24 */ 25 static struct trace_event tevent; 26 static bool tevent_initialized; 27 28 int trace_event__init(struct trace_event *t) 29 { 30 struct pevent *pevent = pevent_alloc(); 31 32 if (pevent) { 33 t->plugin_list = traceevent_load_plugins(pevent); 34 t->pevent = pevent; 35 } 36 37 return pevent ? 0 : -1; 38 } 39 40 static int trace_event__init2(void) 41 { 42 int be = traceevent_host_bigendian(); 43 struct pevent *pevent; 44 45 if (trace_event__init(&tevent)) 46 return -1; 47 48 pevent = tevent.pevent; 49 pevent_set_flag(pevent, PEVENT_NSEC_OUTPUT); 50 pevent_set_file_bigendian(pevent, be); 51 pevent_set_host_bigendian(pevent, be); 52 tevent_initialized = true; 53 return 0; 54 } 55 56 int trace_event__register_resolver(struct machine *machine, 57 pevent_func_resolver_t *func) 58 { 59 if (!tevent_initialized && trace_event__init2()) 60 return -1; 61 62 return pevent_set_function_resolver(tevent.pevent, func, machine); 63 } 64 65 void trace_event__cleanup(struct trace_event *t) 66 { 67 traceevent_unload_plugins(t->plugin_list, t->pevent); 68 pevent_free(t->pevent); 69 } 70 71 /* 72 * Returns pointer with encoded error via <linux/err.h> interface. 73 */ 74 static struct event_format* 75 tp_format(const char *sys, const char *name) 76 { 77 struct pevent *pevent = tevent.pevent; 78 struct event_format *event = NULL; 79 char path[PATH_MAX]; 80 size_t size; 81 char *data; 82 int err; 83 84 scnprintf(path, PATH_MAX, "%s/%s/%s/format", 85 tracing_events_path, sys, name); 86 87 err = filename__read_str(path, &data, &size); 88 if (err) 89 return ERR_PTR(err); 90 91 pevent_parse_format(pevent, &event, data, size, sys); 92 93 free(data); 94 return event; 95 } 96 97 /* 98 * Returns pointer with encoded error via <linux/err.h> interface. 99 */ 100 struct event_format* 101 trace_event__tp_format(const char *sys, const char *name) 102 { 103 if (!tevent_initialized && trace_event__init2()) 104 return ERR_PTR(-ENOMEM); 105 106 return tp_format(sys, name); 107 } 108 109 struct event_format *trace_event__tp_format_id(int id) 110 { 111 if (!tevent_initialized && trace_event__init2()) 112 return ERR_PTR(-ENOMEM); 113 114 return pevent_find_event(tevent.pevent, id); 115 } 116