1 /* 2 * builtin-diff.c 3 * 4 * Builtin diff command: Analyze two perf.data input files, look up and read 5 * DSOs and symbol information, sort them and produce a diff. 6 */ 7 #include "builtin.h" 8 9 #include "util/debug.h" 10 #include "util/event.h" 11 #include "util/hist.h" 12 #include "util/session.h" 13 #include "util/sort.h" 14 #include "util/symbol.h" 15 #include "util/util.h" 16 17 #include <stdlib.h> 18 19 static char const *input_old = "perf.data.old", 20 *input_new = "perf.data"; 21 static char diff__default_sort_order[] = "dso,symbol"; 22 static bool force; 23 static bool show_displacement; 24 25 static int hists__add_entry(struct hists *self, 26 struct addr_location *al, u64 period) 27 { 28 if (__hists__add_entry(self, al, NULL, period) != NULL) 29 return 0; 30 return -ENOMEM; 31 } 32 33 static int diff__process_sample_event(event_t *event, 34 struct sample_data *sample, 35 struct perf_session *session) 36 { 37 struct addr_location al; 38 39 if (event__preprocess_sample(event, session, &al, sample, NULL) < 0) { 40 pr_warning("problem processing %d event, skipping it.\n", 41 event->header.type); 42 return -1; 43 } 44 45 if (al.filtered || al.sym == NULL) 46 return 0; 47 48 if (hists__add_entry(&session->hists, &al, sample->period)) { 49 pr_warning("problem incrementing symbol period, skipping event\n"); 50 return -1; 51 } 52 53 session->hists.stats.total_period += sample->period; 54 return 0; 55 } 56 57 static struct perf_event_ops event_ops = { 58 .sample = diff__process_sample_event, 59 .mmap = event__process_mmap, 60 .comm = event__process_comm, 61 .exit = event__process_task, 62 .fork = event__process_task, 63 .lost = event__process_lost, 64 .ordered_samples = true, 65 .ordering_requires_timestamps = true, 66 }; 67 68 static void perf_session__insert_hist_entry_by_name(struct rb_root *root, 69 struct hist_entry *he) 70 { 71 struct rb_node **p = &root->rb_node; 72 struct rb_node *parent = NULL; 73 struct hist_entry *iter; 74 75 while (*p != NULL) { 76 parent = *p; 77 iter = rb_entry(parent, struct hist_entry, rb_node); 78 if (hist_entry__cmp(he, iter) < 0) 79 p = &(*p)->rb_left; 80 else 81 p = &(*p)->rb_right; 82 } 83 84 rb_link_node(&he->rb_node, parent, p); 85 rb_insert_color(&he->rb_node, root); 86 } 87 88 static void hists__resort_entries(struct hists *self) 89 { 90 unsigned long position = 1; 91 struct rb_root tmp = RB_ROOT; 92 struct rb_node *next = rb_first(&self->entries); 93 94 while (next != NULL) { 95 struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node); 96 97 next = rb_next(&n->rb_node); 98 rb_erase(&n->rb_node, &self->entries); 99 n->position = position++; 100 perf_session__insert_hist_entry_by_name(&tmp, n); 101 } 102 103 self->entries = tmp; 104 } 105 106 static void hists__set_positions(struct hists *self) 107 { 108 hists__output_resort(self); 109 hists__resort_entries(self); 110 } 111 112 static struct hist_entry *hists__find_entry(struct hists *self, 113 struct hist_entry *he) 114 { 115 struct rb_node *n = self->entries.rb_node; 116 117 while (n) { 118 struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node); 119 int64_t cmp = hist_entry__cmp(he, iter); 120 121 if (cmp < 0) 122 n = n->rb_left; 123 else if (cmp > 0) 124 n = n->rb_right; 125 else 126 return iter; 127 } 128 129 return NULL; 130 } 131 132 static void hists__match(struct hists *older, struct hists *newer) 133 { 134 struct rb_node *nd; 135 136 for (nd = rb_first(&newer->entries); nd; nd = rb_next(nd)) { 137 struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node); 138 pos->pair = hists__find_entry(older, pos); 139 } 140 } 141 142 static int __cmd_diff(void) 143 { 144 int ret, i; 145 struct perf_session *session[2]; 146 147 session[0] = perf_session__new(input_old, O_RDONLY, force, false, &event_ops); 148 session[1] = perf_session__new(input_new, O_RDONLY, force, false, &event_ops); 149 if (session[0] == NULL || session[1] == NULL) 150 return -ENOMEM; 151 152 for (i = 0; i < 2; ++i) { 153 ret = perf_session__process_events(session[i], &event_ops); 154 if (ret) 155 goto out_delete; 156 } 157 158 hists__output_resort(&session[1]->hists); 159 if (show_displacement) 160 hists__set_positions(&session[0]->hists); 161 162 hists__match(&session[0]->hists, &session[1]->hists); 163 hists__fprintf(&session[1]->hists, &session[0]->hists, 164 show_displacement, stdout); 165 out_delete: 166 for (i = 0; i < 2; ++i) 167 perf_session__delete(session[i]); 168 return ret; 169 } 170 171 static const char * const diff_usage[] = { 172 "perf diff [<options>] [old_file] [new_file]", 173 NULL, 174 }; 175 176 static const struct option options[] = { 177 OPT_INCR('v', "verbose", &verbose, 178 "be more verbose (show symbol address, etc)"), 179 OPT_BOOLEAN('M', "displacement", &show_displacement, 180 "Show position displacement relative to baseline"), 181 OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, 182 "dump raw trace in ASCII"), 183 OPT_BOOLEAN('f', "force", &force, "don't complain, do it"), 184 OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules, 185 "load module symbols - WARNING: use only with -k and LIVE kernel"), 186 OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]", 187 "only consider symbols in these dsos"), 188 OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]", 189 "only consider symbols in these comms"), 190 OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]", 191 "only consider these symbols"), 192 OPT_STRING('s', "sort", &sort_order, "key[,key2...]", 193 "sort by key(s): pid, comm, dso, symbol, parent"), 194 OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator", 195 "separator for columns, no spaces will be added between " 196 "columns '.' is reserved."), 197 OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory", 198 "Look for files with symbols relative to this directory"), 199 OPT_END() 200 }; 201 202 int cmd_diff(int argc, const char **argv, const char *prefix __used) 203 { 204 sort_order = diff__default_sort_order; 205 argc = parse_options(argc, argv, options, diff_usage, 0); 206 if (argc) { 207 if (argc > 2) 208 usage_with_options(diff_usage, options); 209 if (argc == 2) { 210 input_old = argv[0]; 211 input_new = argv[1]; 212 } else 213 input_new = argv[0]; 214 } else if (symbol_conf.default_guest_vmlinux_name || 215 symbol_conf.default_guest_kallsyms) { 216 input_old = "perf.data.host"; 217 input_new = "perf.data.guest"; 218 } 219 220 symbol_conf.exclude_other = false; 221 if (symbol__init() < 0) 222 return -1; 223 224 setup_sorting(diff_usage, options); 225 setup_pager(); 226 227 sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL); 228 sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL); 229 sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL); 230 231 return __cmd_diff(); 232 } 233