1 // SPDX-License-Identifier: GPL-2.0 2 #include <errno.h> 3 #include <inttypes.h> 4 #include <linux/list.h> 5 #include <linux/compiler.h> 6 #include <linux/string.h> 7 #include "ordered-events.h" 8 #include "session.h" 9 #include "asm/bug.h" 10 #include "debug.h" 11 12 #define pr_N(n, fmt, ...) \ 13 eprintf(n, debug_ordered_events, fmt, ##__VA_ARGS__) 14 15 #define pr(fmt, ...) pr_N(1, pr_fmt(fmt), ##__VA_ARGS__) 16 17 static void queue_event(struct ordered_events *oe, struct ordered_event *new) 18 { 19 struct ordered_event *last = oe->last; 20 u64 timestamp = new->timestamp; 21 struct list_head *p; 22 23 ++oe->nr_events; 24 oe->last = new; 25 26 pr_oe_time2(timestamp, "queue_event nr_events %u\n", oe->nr_events); 27 28 if (!last) { 29 list_add(&new->list, &oe->events); 30 oe->max_timestamp = timestamp; 31 return; 32 } 33 34 /* 35 * last event might point to some random place in the list as it's 36 * the last queued event. We expect that the new event is close to 37 * this. 38 */ 39 if (last->timestamp <= timestamp) { 40 while (last->timestamp <= timestamp) { 41 p = last->list.next; 42 if (p == &oe->events) { 43 list_add_tail(&new->list, &oe->events); 44 oe->max_timestamp = timestamp; 45 return; 46 } 47 last = list_entry(p, struct ordered_event, list); 48 } 49 list_add_tail(&new->list, &last->list); 50 } else { 51 while (last->timestamp > timestamp) { 52 p = last->list.prev; 53 if (p == &oe->events) { 54 list_add(&new->list, &oe->events); 55 return; 56 } 57 last = list_entry(p, struct ordered_event, list); 58 } 59 list_add(&new->list, &last->list); 60 } 61 } 62 63 static union perf_event *__dup_event(struct ordered_events *oe, 64 union perf_event *event) 65 { 66 union perf_event *new_event = NULL; 67 68 if (oe->cur_alloc_size < oe->max_alloc_size) { 69 new_event = memdup(event, event->header.size); 70 if (new_event) 71 oe->cur_alloc_size += event->header.size; 72 } 73 74 return new_event; 75 } 76 77 static union perf_event *dup_event(struct ordered_events *oe, 78 union perf_event *event) 79 { 80 return oe->copy_on_queue ? __dup_event(oe, event) : event; 81 } 82 83 static void free_dup_event(struct ordered_events *oe, union perf_event *event) 84 { 85 if (event && oe->copy_on_queue) { 86 oe->cur_alloc_size -= event->header.size; 87 free(event); 88 } 89 } 90 91 #define MAX_SAMPLE_BUFFER (64 * 1024 / sizeof(struct ordered_event)) 92 static struct ordered_event *alloc_event(struct ordered_events *oe, 93 union perf_event *event) 94 { 95 struct list_head *cache = &oe->cache; 96 struct ordered_event *new = NULL; 97 union perf_event *new_event; 98 99 new_event = dup_event(oe, event); 100 if (!new_event) 101 return NULL; 102 103 if (!list_empty(cache)) { 104 new = list_entry(cache->next, struct ordered_event, list); 105 list_del(&new->list); 106 } else if (oe->buffer) { 107 new = oe->buffer + oe->buffer_idx; 108 if (++oe->buffer_idx == MAX_SAMPLE_BUFFER) 109 oe->buffer = NULL; 110 } else if (oe->cur_alloc_size < oe->max_alloc_size) { 111 size_t size = MAX_SAMPLE_BUFFER * sizeof(*new); 112 113 oe->buffer = malloc(size); 114 if (!oe->buffer) { 115 free_dup_event(oe, new_event); 116 return NULL; 117 } 118 119 pr("alloc size %" PRIu64 "B (+%zu), max %" PRIu64 "B\n", 120 oe->cur_alloc_size, size, oe->max_alloc_size); 121 122 oe->cur_alloc_size += size; 123 list_add(&oe->buffer->list, &oe->to_free); 124 125 /* First entry is abused to maintain the to_free list. */ 126 oe->buffer_idx = 2; 127 new = oe->buffer + 1; 128 } else { 129 pr("allocation limit reached %" PRIu64 "B\n", oe->max_alloc_size); 130 } 131 132 new->event = new_event; 133 return new; 134 } 135 136 static struct ordered_event * 137 ordered_events__new_event(struct ordered_events *oe, u64 timestamp, 138 union perf_event *event) 139 { 140 struct ordered_event *new; 141 142 new = alloc_event(oe, event); 143 if (new) { 144 new->timestamp = timestamp; 145 queue_event(oe, new); 146 } 147 148 return new; 149 } 150 151 void ordered_events__delete(struct ordered_events *oe, struct ordered_event *event) 152 { 153 list_move(&event->list, &oe->cache); 154 oe->nr_events--; 155 free_dup_event(oe, event->event); 156 event->event = NULL; 157 } 158 159 int ordered_events__queue(struct ordered_events *oe, union perf_event *event, 160 u64 timestamp, u64 file_offset) 161 { 162 struct ordered_event *oevent; 163 164 if (!timestamp || timestamp == ~0ULL) 165 return -ETIME; 166 167 if (timestamp < oe->last_flush) { 168 pr_oe_time(timestamp, "out of order event\n"); 169 pr_oe_time(oe->last_flush, "last flush, last_flush_type %d\n", 170 oe->last_flush_type); 171 172 oe->nr_unordered_events++; 173 } 174 175 oevent = ordered_events__new_event(oe, timestamp, event); 176 if (!oevent) { 177 ordered_events__flush(oe, OE_FLUSH__HALF); 178 oevent = ordered_events__new_event(oe, timestamp, event); 179 } 180 181 if (!oevent) 182 return -ENOMEM; 183 184 oevent->file_offset = file_offset; 185 return 0; 186 } 187 188 static int __ordered_events__flush(struct ordered_events *oe) 189 { 190 struct list_head *head = &oe->events; 191 struct ordered_event *tmp, *iter; 192 u64 limit = oe->next_flush; 193 u64 last_ts = oe->last ? oe->last->timestamp : 0ULL; 194 bool show_progress = limit == ULLONG_MAX; 195 struct ui_progress prog; 196 int ret; 197 198 if (!limit) 199 return 0; 200 201 if (show_progress) 202 ui_progress__init(&prog, oe->nr_events, "Processing time ordered events..."); 203 204 list_for_each_entry_safe(iter, tmp, head, list) { 205 if (session_done()) 206 return 0; 207 208 if (iter->timestamp > limit) 209 break; 210 ret = oe->deliver(oe, iter); 211 if (ret) 212 return ret; 213 214 ordered_events__delete(oe, iter); 215 oe->last_flush = iter->timestamp; 216 217 if (show_progress) 218 ui_progress__update(&prog, 1); 219 } 220 221 if (list_empty(head)) 222 oe->last = NULL; 223 else if (last_ts <= limit) 224 oe->last = list_entry(head->prev, struct ordered_event, list); 225 226 if (show_progress) 227 ui_progress__finish(); 228 229 return 0; 230 } 231 232 int ordered_events__flush(struct ordered_events *oe, enum oe_flush how) 233 { 234 static const char * const str[] = { 235 "NONE", 236 "FINAL", 237 "ROUND", 238 "HALF ", 239 }; 240 int err; 241 242 if (oe->nr_events == 0) 243 return 0; 244 245 switch (how) { 246 case OE_FLUSH__FINAL: 247 oe->next_flush = ULLONG_MAX; 248 break; 249 250 case OE_FLUSH__HALF: 251 { 252 struct ordered_event *first, *last; 253 struct list_head *head = &oe->events; 254 255 first = list_entry(head->next, struct ordered_event, list); 256 last = oe->last; 257 258 /* Warn if we are called before any event got allocated. */ 259 if (WARN_ONCE(!last || list_empty(head), "empty queue")) 260 return 0; 261 262 oe->next_flush = first->timestamp; 263 oe->next_flush += (last->timestamp - first->timestamp) / 2; 264 break; 265 } 266 267 case OE_FLUSH__ROUND: 268 case OE_FLUSH__NONE: 269 default: 270 break; 271 }; 272 273 pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush PRE %s, nr_events %u\n", 274 str[how], oe->nr_events); 275 pr_oe_time(oe->max_timestamp, "max_timestamp\n"); 276 277 err = __ordered_events__flush(oe); 278 279 if (!err) { 280 if (how == OE_FLUSH__ROUND) 281 oe->next_flush = oe->max_timestamp; 282 283 oe->last_flush_type = how; 284 } 285 286 pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush POST %s, nr_events %u\n", 287 str[how], oe->nr_events); 288 pr_oe_time(oe->last_flush, "last_flush\n"); 289 290 return err; 291 } 292 293 void ordered_events__init(struct ordered_events *oe, ordered_events__deliver_t deliver) 294 { 295 INIT_LIST_HEAD(&oe->events); 296 INIT_LIST_HEAD(&oe->cache); 297 INIT_LIST_HEAD(&oe->to_free); 298 oe->max_alloc_size = (u64) -1; 299 oe->cur_alloc_size = 0; 300 oe->deliver = deliver; 301 } 302 303 void ordered_events__free(struct ordered_events *oe) 304 { 305 while (!list_empty(&oe->to_free)) { 306 struct ordered_event *event; 307 308 event = list_entry(oe->to_free.next, struct ordered_event, list); 309 list_del(&event->list); 310 free_dup_event(oe, event->event); 311 free(event); 312 } 313 } 314 315 void ordered_events__reinit(struct ordered_events *oe) 316 { 317 ordered_events__deliver_t old_deliver = oe->deliver; 318 319 ordered_events__free(oe); 320 memset(oe, '\0', sizeof(*oe)); 321 ordered_events__init(oe, old_deliver); 322 } 323