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Commit | Line | Data |
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96872bc2 LT |
1 | /* |
2 | * name-hash.c | |
3 | * | |
4 | * Hashing names in the index state | |
5 | * | |
6 | * Copyright (C) 2008 Linus Torvalds | |
7 | */ | |
96872bc2 | 8 | #include "cache.h" |
07642942 | 9 | #include "thread-utils.h" |
96872bc2 | 10 | |
2092678c | 11 | struct dir_entry { |
e05881a4 | 12 | struct hashmap_entry ent; |
2092678c | 13 | struct dir_entry *parent; |
2092678c KB |
14 | int nr; |
15 | unsigned int namelen; | |
41284eb0 | 16 | char name[FLEX_ARRAY]; |
2092678c KB |
17 | }; |
18 | ||
7663cdc8 | 19 | static int dir_entry_cmp(const void *unused_cmp_data, |
56a14ea7 SB |
20 | const void *entry, |
21 | const void *entry_or_key, | |
22 | const void *keydata) | |
e05881a4 | 23 | { |
56a14ea7 SB |
24 | const struct dir_entry *e1 = entry; |
25 | const struct dir_entry *e2 = entry_or_key; | |
26 | const char *name = keydata; | |
27 | ||
41284eb0 DT |
28 | return e1->namelen != e2->namelen || strncasecmp(e1->name, |
29 | name ? name : e2->name, e1->namelen); | |
e05881a4 KB |
30 | } |
31 | ||
846df809 JH |
32 | static struct dir_entry *find_dir_entry__hash(struct index_state *istate, |
33 | const char *name, unsigned int namelen, unsigned int hash) | |
2092678c | 34 | { |
e05881a4 | 35 | struct dir_entry key; |
846df809 | 36 | hashmap_entry_init(&key, hash); |
e05881a4 KB |
37 | key.namelen = namelen; |
38 | return hashmap_get(&istate->dir_hash, &key, name); | |
2092678c KB |
39 | } |
40 | ||
846df809 JH |
41 | static struct dir_entry *find_dir_entry(struct index_state *istate, |
42 | const char *name, unsigned int namelen) | |
43 | { | |
44 | return find_dir_entry__hash(istate, name, namelen, memihash(name, namelen)); | |
45 | } | |
46 | ||
2092678c KB |
47 | static struct dir_entry *hash_dir_entry(struct index_state *istate, |
48 | struct cache_entry *ce, int namelen) | |
5102c617 JJ |
49 | { |
50 | /* | |
51 | * Throw each directory component in the hash for quick lookup | |
d28eec26 | 52 | * during a git status. Directory components are stored without their |
5102c617 | 53 | * closing slash. Despite submodules being a directory, they never |
d28eec26 | 54 | * reach this point, because they are stored |
2092678c | 55 | * in index_state.name_hash (as ordinary cache_entries). |
5102c617 | 56 | */ |
2092678c KB |
57 | struct dir_entry *dir; |
58 | ||
59 | /* get length of parent directory */ | |
60 | while (namelen > 0 && !is_dir_sep(ce->name[namelen - 1])) | |
61 | namelen--; | |
62 | if (namelen <= 0) | |
63 | return NULL; | |
d28eec26 | 64 | namelen--; |
2092678c KB |
65 | |
66 | /* lookup existing entry for that directory */ | |
67 | dir = find_dir_entry(istate, ce->name, namelen); | |
68 | if (!dir) { | |
69 | /* not found, create it and add to hash table */ | |
96ffc06f | 70 | FLEX_ALLOC_MEM(dir, name, ce->name, namelen); |
e05881a4 | 71 | hashmap_entry_init(dir, memihash(ce->name, namelen)); |
2092678c | 72 | dir->namelen = namelen; |
e05881a4 | 73 | hashmap_add(&istate->dir_hash, dir); |
2092678c KB |
74 | |
75 | /* recursively add missing parent directories */ | |
d28eec26 | 76 | dir->parent = hash_dir_entry(istate, ce, namelen); |
5102c617 | 77 | } |
2092678c KB |
78 | return dir; |
79 | } | |
80 | ||
81 | static void add_dir_entry(struct index_state *istate, struct cache_entry *ce) | |
82 | { | |
83 | /* Add reference to the directory entry (and parents if 0). */ | |
84 | struct dir_entry *dir = hash_dir_entry(istate, ce, ce_namelen(ce)); | |
85 | while (dir && !(dir->nr++)) | |
86 | dir = dir->parent; | |
87 | } | |
88 | ||
89 | static void remove_dir_entry(struct index_state *istate, struct cache_entry *ce) | |
90 | { | |
91 | /* | |
1c8cca19 KB |
92 | * Release reference to the directory entry. If 0, remove and continue |
93 | * with parent directory. | |
2092678c KB |
94 | */ |
95 | struct dir_entry *dir = hash_dir_entry(istate, ce, ce_namelen(ce)); | |
1c8cca19 KB |
96 | while (dir && !(--dir->nr)) { |
97 | struct dir_entry *parent = dir->parent; | |
98 | hashmap_remove(&istate->dir_hash, dir, NULL); | |
99 | free(dir); | |
100 | dir = parent; | |
101 | } | |
5102c617 JJ |
102 | } |
103 | ||
96872bc2 LT |
104 | static void hash_index_entry(struct index_state *istate, struct cache_entry *ce) |
105 | { | |
96872bc2 LT |
106 | if (ce->ce_flags & CE_HASHED) |
107 | return; | |
108 | ce->ce_flags |= CE_HASHED; | |
8b013788 KB |
109 | hashmap_entry_init(ce, memihash(ce->name, ce_namelen(ce))); |
110 | hashmap_add(&istate->name_hash, ce); | |
5102c617 | 111 | |
419a597f | 112 | if (ignore_case) |
2092678c | 113 | add_dir_entry(istate, ce); |
96872bc2 LT |
114 | } |
115 | ||
7663cdc8 | 116 | static int cache_entry_cmp(const void *unused_cmp_data, |
56a14ea7 SB |
117 | const void *entry, |
118 | const void *entry_or_key, | |
7663cdc8 | 119 | const void *remove) |
419a597f | 120 | { |
56a14ea7 SB |
121 | const struct cache_entry *ce1 = entry; |
122 | const struct cache_entry *ce2 = entry_or_key; | |
419a597f KB |
123 | /* |
124 | * For remove_name_hash, find the exact entry (pointer equality); for | |
7b359ea6 | 125 | * index_file_exists, find all entries with matching hash code and |
419a597f KB |
126 | * decide whether the entry matches in same_name. |
127 | */ | |
128 | return remove ? !(ce1 == ce2) : 0; | |
129 | } | |
130 | ||
846df809 JH |
131 | static int lazy_try_threaded = 1; |
132 | static int lazy_nr_dir_threads; | |
133 | ||
846df809 JH |
134 | /* |
135 | * Set a minimum number of cache_entries that we will handle per | |
136 | * thread and use that to decide how many threads to run (upto | |
137 | * the number on the system). | |
138 | * | |
139 | * For guidance setting the lower per-thread bound, see: | |
140 | * t/helper/test-lazy-init-name-hash --analyze | |
141 | */ | |
142 | #define LAZY_THREAD_COST (2000) | |
143 | ||
144 | /* | |
145 | * We use n mutexes to guard n partitions of the "istate->dir_hash" | |
146 | * hashtable. Since "find" and "insert" operations will hash to a | |
147 | * particular bucket and modify/search a single chain, we can say | |
148 | * that "all chains mod n" are guarded by the same mutex -- rather | |
149 | * than having a single mutex to guard the entire table. (This does | |
150 | * require that we disable "rehashing" on the hashtable.) | |
151 | * | |
152 | * So, a larger value here decreases the probability of a collision | |
153 | * and the time that each thread must wait for the mutex. | |
154 | */ | |
155 | #define LAZY_MAX_MUTEX (32) | |
156 | ||
157 | static pthread_mutex_t *lazy_dir_mutex_array; | |
158 | ||
159 | /* | |
160 | * An array of lazy_entry items is used by the n threads in | |
161 | * the directory parse (first) phase to (lock-free) store the | |
162 | * intermediate results. These values are then referenced by | |
163 | * the 2 threads in the second phase. | |
164 | */ | |
165 | struct lazy_entry { | |
166 | struct dir_entry *dir; | |
167 | unsigned int hash_dir; | |
168 | unsigned int hash_name; | |
169 | }; | |
170 | ||
171 | /* | |
172 | * Decide if we want to use threads (if available) to load | |
173 | * the hash tables. We set "lazy_nr_dir_threads" to zero when | |
174 | * it is not worth it. | |
175 | */ | |
176 | static int lookup_lazy_params(struct index_state *istate) | |
177 | { | |
178 | int nr_cpus; | |
179 | ||
180 | lazy_nr_dir_threads = 0; | |
181 | ||
182 | if (!lazy_try_threaded) | |
183 | return 0; | |
184 | ||
185 | /* | |
186 | * If we are respecting case, just use the original | |
187 | * code to build the "istate->name_hash". We don't | |
188 | * need the complexity here. | |
189 | */ | |
190 | if (!ignore_case) | |
191 | return 0; | |
192 | ||
193 | nr_cpus = online_cpus(); | |
194 | if (nr_cpus < 2) | |
195 | return 0; | |
196 | ||
197 | if (istate->cache_nr < 2 * LAZY_THREAD_COST) | |
198 | return 0; | |
96872bc2 | 199 | |
846df809 JH |
200 | if (istate->cache_nr < nr_cpus * LAZY_THREAD_COST) |
201 | nr_cpus = istate->cache_nr / LAZY_THREAD_COST; | |
202 | lazy_nr_dir_threads = nr_cpus; | |
203 | return lazy_nr_dir_threads; | |
204 | } | |
205 | ||
206 | /* | |
207 | * Initialize n mutexes for use when searching and inserting | |
208 | * into "istate->dir_hash". All "dir" threads are trying | |
209 | * to insert partial pathnames into the hash as they iterate | |
210 | * over their portions of the index, so lock contention is | |
211 | * high. | |
212 | * | |
213 | * However, the hashmap is going to put items into bucket | |
214 | * chains based on their hash values. Use that to create n | |
215 | * mutexes and lock on mutex[bucket(hash) % n]. This will | |
216 | * decrease the collision rate by (hopefully) by a factor of n. | |
217 | */ | |
218 | static void init_dir_mutex(void) | |
219 | { | |
220 | int j; | |
221 | ||
222 | lazy_dir_mutex_array = xcalloc(LAZY_MAX_MUTEX, sizeof(pthread_mutex_t)); | |
223 | ||
224 | for (j = 0; j < LAZY_MAX_MUTEX; j++) | |
225 | init_recursive_mutex(&lazy_dir_mutex_array[j]); | |
226 | } | |
227 | ||
228 | static void cleanup_dir_mutex(void) | |
229 | { | |
230 | int j; | |
231 | ||
232 | for (j = 0; j < LAZY_MAX_MUTEX; j++) | |
233 | pthread_mutex_destroy(&lazy_dir_mutex_array[j]); | |
234 | ||
235 | free(lazy_dir_mutex_array); | |
236 | } | |
237 | ||
238 | static void lock_dir_mutex(int j) | |
239 | { | |
240 | pthread_mutex_lock(&lazy_dir_mutex_array[j]); | |
241 | } | |
242 | ||
243 | static void unlock_dir_mutex(int j) | |
244 | { | |
245 | pthread_mutex_unlock(&lazy_dir_mutex_array[j]); | |
246 | } | |
247 | ||
248 | static inline int compute_dir_lock_nr( | |
249 | const struct hashmap *map, | |
250 | unsigned int hash) | |
251 | { | |
252 | return hashmap_bucket(map, hash) % LAZY_MAX_MUTEX; | |
253 | } | |
254 | ||
255 | static struct dir_entry *hash_dir_entry_with_parent_and_prefix( | |
256 | struct index_state *istate, | |
257 | struct dir_entry *parent, | |
258 | struct strbuf *prefix) | |
259 | { | |
260 | struct dir_entry *dir; | |
261 | unsigned int hash; | |
262 | int lock_nr; | |
263 | ||
264 | /* | |
265 | * Either we have a parent directory and path with slash(es) | |
266 | * or the directory is an immediate child of the root directory. | |
267 | */ | |
268 | assert((parent != NULL) ^ (strchr(prefix->buf, '/') == NULL)); | |
269 | ||
270 | if (parent) | |
271 | hash = memihash_cont(parent->ent.hash, | |
272 | prefix->buf + parent->namelen, | |
273 | prefix->len - parent->namelen); | |
274 | else | |
275 | hash = memihash(prefix->buf, prefix->len); | |
276 | ||
277 | lock_nr = compute_dir_lock_nr(&istate->dir_hash, hash); | |
278 | lock_dir_mutex(lock_nr); | |
279 | ||
280 | dir = find_dir_entry__hash(istate, prefix->buf, prefix->len, hash); | |
281 | if (!dir) { | |
282 | FLEX_ALLOC_MEM(dir, name, prefix->buf, prefix->len); | |
283 | hashmap_entry_init(dir, hash); | |
284 | dir->namelen = prefix->len; | |
285 | dir->parent = parent; | |
286 | hashmap_add(&istate->dir_hash, dir); | |
287 | ||
288 | if (parent) { | |
289 | unlock_dir_mutex(lock_nr); | |
290 | ||
291 | /* All I really need here is an InterlockedIncrement(&(parent->nr)) */ | |
292 | lock_nr = compute_dir_lock_nr(&istate->dir_hash, parent->ent.hash); | |
293 | lock_dir_mutex(lock_nr); | |
294 | parent->nr++; | |
295 | } | |
296 | } | |
297 | ||
298 | unlock_dir_mutex(lock_nr); | |
299 | ||
300 | return dir; | |
301 | } | |
302 | ||
303 | /* | |
304 | * handle_range_1() and handle_range_dir() are derived from | |
305 | * clear_ce_flags_1() and clear_ce_flags_dir() in unpack-trees.c | |
306 | * and handle the iteration over the entire array of index entries. | |
307 | * They use recursion for adjacent entries in the same parent | |
308 | * directory. | |
309 | */ | |
310 | static int handle_range_1( | |
311 | struct index_state *istate, | |
312 | int k_start, | |
313 | int k_end, | |
314 | struct dir_entry *parent, | |
315 | struct strbuf *prefix, | |
316 | struct lazy_entry *lazy_entries); | |
317 | ||
318 | static int handle_range_dir( | |
319 | struct index_state *istate, | |
320 | int k_start, | |
321 | int k_end, | |
322 | struct dir_entry *parent, | |
323 | struct strbuf *prefix, | |
324 | struct lazy_entry *lazy_entries, | |
325 | struct dir_entry **dir_new_out) | |
326 | { | |
327 | int rc, k; | |
328 | int input_prefix_len = prefix->len; | |
329 | struct dir_entry *dir_new; | |
330 | ||
331 | dir_new = hash_dir_entry_with_parent_and_prefix(istate, parent, prefix); | |
332 | ||
333 | strbuf_addch(prefix, '/'); | |
334 | ||
335 | /* | |
336 | * Scan forward in the index array for index entries having the same | |
337 | * path prefix (that are also in this directory). | |
338 | */ | |
2a1bd45b KW |
339 | if (k_start + 1 >= k_end) |
340 | k = k_end; | |
341 | else if (strncmp(istate->cache[k_start + 1]->name, prefix->buf, prefix->len) > 0) | |
846df809 JH |
342 | k = k_start + 1; |
343 | else if (strncmp(istate->cache[k_end - 1]->name, prefix->buf, prefix->len) == 0) | |
344 | k = k_end; | |
345 | else { | |
346 | int begin = k_start; | |
347 | int end = k_end; | |
348 | while (begin < end) { | |
349 | int mid = (begin + end) >> 1; | |
350 | int cmp = strncmp(istate->cache[mid]->name, prefix->buf, prefix->len); | |
351 | if (cmp == 0) /* mid has same prefix; look in second part */ | |
352 | begin = mid + 1; | |
353 | else if (cmp > 0) /* mid is past group; look in first part */ | |
354 | end = mid; | |
355 | else | |
356 | die("cache entry out of order"); | |
357 | } | |
358 | k = begin; | |
359 | } | |
360 | ||
361 | /* | |
362 | * Recurse and process what we can of this subset [k_start, k). | |
363 | */ | |
364 | rc = handle_range_1(istate, k_start, k, dir_new, prefix, lazy_entries); | |
365 | ||
366 | strbuf_setlen(prefix, input_prefix_len); | |
367 | ||
368 | *dir_new_out = dir_new; | |
369 | return rc; | |
370 | } | |
371 | ||
372 | static int handle_range_1( | |
373 | struct index_state *istate, | |
374 | int k_start, | |
375 | int k_end, | |
376 | struct dir_entry *parent, | |
377 | struct strbuf *prefix, | |
378 | struct lazy_entry *lazy_entries) | |
379 | { | |
380 | int input_prefix_len = prefix->len; | |
381 | int k = k_start; | |
382 | ||
383 | while (k < k_end) { | |
384 | struct cache_entry *ce_k = istate->cache[k]; | |
385 | const char *name, *slash; | |
386 | ||
387 | if (prefix->len && strncmp(ce_k->name, prefix->buf, prefix->len)) | |
388 | break; | |
389 | ||
390 | name = ce_k->name + prefix->len; | |
391 | slash = strchr(name, '/'); | |
392 | ||
393 | if (slash) { | |
394 | int len = slash - name; | |
395 | int processed; | |
396 | struct dir_entry *dir_new; | |
397 | ||
398 | strbuf_add(prefix, name, len); | |
399 | processed = handle_range_dir(istate, k, k_end, parent, prefix, lazy_entries, &dir_new); | |
400 | if (processed) { | |
401 | k += processed; | |
402 | strbuf_setlen(prefix, input_prefix_len); | |
403 | continue; | |
404 | } | |
405 | ||
406 | strbuf_addch(prefix, '/'); | |
407 | processed = handle_range_1(istate, k, k_end, dir_new, prefix, lazy_entries); | |
408 | k += processed; | |
409 | strbuf_setlen(prefix, input_prefix_len); | |
410 | continue; | |
411 | } | |
412 | ||
413 | /* | |
414 | * It is too expensive to take a lock to insert "ce_k" | |
415 | * into "istate->name_hash" and increment the ref-count | |
416 | * on the "parent" dir. So we defer actually updating | |
417 | * permanent data structures until phase 2 (where we | |
418 | * can change the locking requirements) and simply | |
419 | * accumulate our current results into the lazy_entries | |
420 | * data array). | |
421 | * | |
422 | * We do not need to lock the lazy_entries array because | |
423 | * we have exclusive access to the cells in the range | |
424 | * [k_start,k_end) that this thread was given. | |
425 | */ | |
426 | lazy_entries[k].dir = parent; | |
427 | if (parent) { | |
428 | lazy_entries[k].hash_name = memihash_cont( | |
429 | parent->ent.hash, | |
430 | ce_k->name + parent->namelen, | |
431 | ce_namelen(ce_k) - parent->namelen); | |
432 | lazy_entries[k].hash_dir = parent->ent.hash; | |
433 | } else { | |
434 | lazy_entries[k].hash_name = memihash(ce_k->name, ce_namelen(ce_k)); | |
435 | } | |
436 | ||
437 | k++; | |
438 | } | |
439 | ||
440 | return k - k_start; | |
441 | } | |
442 | ||
443 | struct lazy_dir_thread_data { | |
444 | pthread_t pthread; | |
445 | struct index_state *istate; | |
446 | struct lazy_entry *lazy_entries; | |
447 | int k_start; | |
448 | int k_end; | |
449 | }; | |
450 | ||
451 | static void *lazy_dir_thread_proc(void *_data) | |
452 | { | |
453 | struct lazy_dir_thread_data *d = _data; | |
454 | struct strbuf prefix = STRBUF_INIT; | |
455 | handle_range_1(d->istate, d->k_start, d->k_end, NULL, &prefix, d->lazy_entries); | |
456 | strbuf_release(&prefix); | |
457 | return NULL; | |
458 | } | |
459 | ||
460 | struct lazy_name_thread_data { | |
461 | pthread_t pthread; | |
462 | struct index_state *istate; | |
463 | struct lazy_entry *lazy_entries; | |
464 | }; | |
465 | ||
466 | static void *lazy_name_thread_proc(void *_data) | |
467 | { | |
468 | struct lazy_name_thread_data *d = _data; | |
469 | int k; | |
470 | ||
471 | for (k = 0; k < d->istate->cache_nr; k++) { | |
472 | struct cache_entry *ce_k = d->istate->cache[k]; | |
473 | ce_k->ce_flags |= CE_HASHED; | |
474 | hashmap_entry_init(ce_k, d->lazy_entries[k].hash_name); | |
475 | hashmap_add(&d->istate->name_hash, ce_k); | |
476 | } | |
477 | ||
478 | return NULL; | |
479 | } | |
480 | ||
481 | static inline void lazy_update_dir_ref_counts( | |
482 | struct index_state *istate, | |
483 | struct lazy_entry *lazy_entries) | |
484 | { | |
485 | int k; | |
486 | ||
487 | for (k = 0; k < istate->cache_nr; k++) { | |
488 | if (lazy_entries[k].dir) | |
489 | lazy_entries[k].dir->nr++; | |
490 | } | |
491 | } | |
492 | ||
493 | static void threaded_lazy_init_name_hash( | |
494 | struct index_state *istate) | |
495 | { | |
2179045f | 496 | int err; |
846df809 JH |
497 | int nr_each; |
498 | int k_start; | |
499 | int t; | |
500 | struct lazy_entry *lazy_entries; | |
501 | struct lazy_dir_thread_data *td_dir; | |
502 | struct lazy_name_thread_data *td_name; | |
503 | ||
07642942 NTND |
504 | if (!HAVE_THREADS) |
505 | return; | |
506 | ||
846df809 JH |
507 | k_start = 0; |
508 | nr_each = DIV_ROUND_UP(istate->cache_nr, lazy_nr_dir_threads); | |
509 | ||
510 | lazy_entries = xcalloc(istate->cache_nr, sizeof(struct lazy_entry)); | |
511 | td_dir = xcalloc(lazy_nr_dir_threads, sizeof(struct lazy_dir_thread_data)); | |
512 | td_name = xcalloc(1, sizeof(struct lazy_name_thread_data)); | |
513 | ||
514 | init_dir_mutex(); | |
515 | ||
516 | /* | |
517 | * Phase 1: | |
518 | * Build "istate->dir_hash" using n "dir" threads (and a read-only index). | |
519 | */ | |
520 | for (t = 0; t < lazy_nr_dir_threads; t++) { | |
521 | struct lazy_dir_thread_data *td_dir_t = td_dir + t; | |
522 | td_dir_t->istate = istate; | |
523 | td_dir_t->lazy_entries = lazy_entries; | |
524 | td_dir_t->k_start = k_start; | |
525 | k_start += nr_each; | |
526 | if (k_start > istate->cache_nr) | |
527 | k_start = istate->cache_nr; | |
528 | td_dir_t->k_end = k_start; | |
2179045f NTND |
529 | err = pthread_create(&td_dir_t->pthread, NULL, lazy_dir_thread_proc, td_dir_t); |
530 | if (err) | |
531 | die(_("unable to create lazy_dir thread: %s"), strerror(err)); | |
846df809 JH |
532 | } |
533 | for (t = 0; t < lazy_nr_dir_threads; t++) { | |
534 | struct lazy_dir_thread_data *td_dir_t = td_dir + t; | |
535 | if (pthread_join(td_dir_t->pthread, NULL)) | |
536 | die("unable to join lazy_dir_thread"); | |
537 | } | |
538 | ||
539 | /* | |
540 | * Phase 2: | |
541 | * Iterate over all index entries and add them to the "istate->name_hash" | |
542 | * using a single "name" background thread. | |
543 | * (Testing showed it wasn't worth running more than 1 thread for this.) | |
544 | * | |
545 | * Meanwhile, finish updating the parent directory ref-counts for each | |
546 | * index entry using the current thread. (This step is very fast and | |
547 | * doesn't need threading.) | |
548 | */ | |
549 | td_name->istate = istate; | |
550 | td_name->lazy_entries = lazy_entries; | |
2179045f NTND |
551 | err = pthread_create(&td_name->pthread, NULL, lazy_name_thread_proc, td_name); |
552 | if (err) | |
553 | die(_("unable to create lazy_name thread: %s"), strerror(err)); | |
846df809 JH |
554 | |
555 | lazy_update_dir_ref_counts(istate, lazy_entries); | |
556 | ||
2179045f NTND |
557 | err = pthread_join(td_name->pthread, NULL); |
558 | if (err) | |
559 | die(_("unable to join lazy_name thread: %s"), strerror(err)); | |
846df809 JH |
560 | |
561 | cleanup_dir_mutex(); | |
562 | ||
563 | free(td_name); | |
564 | free(td_dir); | |
565 | free(lazy_entries); | |
566 | } | |
567 | ||
846df809 JH |
568 | static void lazy_init_name_hash(struct index_state *istate) |
569 | { | |
ca54d9ba | 570 | |
96872bc2 LT |
571 | if (istate->name_hash_initialized) |
572 | return; | |
c46c406a | 573 | trace_performance_enter(); |
56a14ea7 SB |
574 | hashmap_init(&istate->name_hash, cache_entry_cmp, NULL, istate->cache_nr); |
575 | hashmap_init(&istate->dir_hash, dir_entry_cmp, NULL, istate->cache_nr); | |
846df809 JH |
576 | |
577 | if (lookup_lazy_params(istate)) { | |
8b604d19 JH |
578 | /* |
579 | * Disable item counting and automatic rehashing because | |
580 | * we do per-chain (mod n) locking rather than whole hashmap | |
581 | * locking and we need to prevent the table-size from changing | |
582 | * and bucket items from being redistributed. | |
583 | */ | |
584 | hashmap_disable_item_counting(&istate->dir_hash); | |
846df809 | 585 | threaded_lazy_init_name_hash(istate); |
8b604d19 | 586 | hashmap_enable_item_counting(&istate->dir_hash); |
846df809 JH |
587 | } else { |
588 | int nr; | |
589 | for (nr = 0; nr < istate->cache_nr; nr++) | |
590 | hash_index_entry(istate, istate->cache[nr]); | |
591 | } | |
592 | ||
96872bc2 | 593 | istate->name_hash_initialized = 1; |
c46c406a | 594 | trace_performance_leave("initialize name hash"); |
96872bc2 LT |
595 | } |
596 | ||
846df809 JH |
597 | /* |
598 | * A test routine for t/helper/ sources. | |
599 | * | |
600 | * Returns the number of threads used or 0 when | |
601 | * the non-threaded code path was used. | |
602 | * | |
603 | * Requesting threading WILL NOT override guards | |
604 | * in lookup_lazy_params(). | |
605 | */ | |
606 | int test_lazy_init_name_hash(struct index_state *istate, int try_threaded) | |
607 | { | |
608 | lazy_nr_dir_threads = 0; | |
609 | lazy_try_threaded = try_threaded; | |
610 | ||
611 | lazy_init_name_hash(istate); | |
612 | ||
613 | return lazy_nr_dir_threads; | |
614 | } | |
615 | ||
96872bc2 LT |
616 | void add_name_hash(struct index_state *istate, struct cache_entry *ce) |
617 | { | |
96872bc2 LT |
618 | if (istate->name_hash_initialized) |
619 | hash_index_entry(istate, ce); | |
620 | } | |
621 | ||
2092678c KB |
622 | void remove_name_hash(struct index_state *istate, struct cache_entry *ce) |
623 | { | |
419a597f KB |
624 | if (!istate->name_hash_initialized || !(ce->ce_flags & CE_HASHED)) |
625 | return; | |
626 | ce->ce_flags &= ~CE_HASHED; | |
627 | hashmap_remove(&istate->name_hash, ce, ce); | |
2092678c | 628 | |
419a597f KB |
629 | if (ignore_case) |
630 | remove_dir_entry(istate, ce); | |
2092678c KB |
631 | } |
632 | ||
cd2fef59 LT |
633 | static int slow_same_name(const char *name1, int len1, const char *name2, int len2) |
634 | { | |
635 | if (len1 != len2) | |
636 | return 0; | |
637 | ||
638 | while (len1) { | |
639 | unsigned char c1 = *name1++; | |
640 | unsigned char c2 = *name2++; | |
641 | len1--; | |
642 | if (c1 != c2) { | |
643 | c1 = toupper(c1); | |
644 | c2 = toupper(c2); | |
645 | if (c1 != c2) | |
646 | return 0; | |
647 | } | |
648 | } | |
649 | return 1; | |
650 | } | |
651 | ||
652 | static int same_name(const struct cache_entry *ce, const char *name, int namelen, int icase) | |
653 | { | |
654 | int len = ce_namelen(ce); | |
655 | ||
656 | /* | |
657 | * Always do exact compare, even if we want a case-ignoring comparison; | |
658 | * we do the quick exact one first, because it will be the common case. | |
659 | */ | |
be99ec97 | 660 | if (len == namelen && !memcmp(name, ce->name, len)) |
cd2fef59 LT |
661 | return 1; |
662 | ||
5102c617 JJ |
663 | if (!icase) |
664 | return 0; | |
665 | ||
2092678c | 666 | return slow_same_name(name, namelen, ce->name, len); |
cd2fef59 LT |
667 | } |
668 | ||
41284eb0 | 669 | int index_dir_exists(struct index_state *istate, const char *name, int namelen) |
db5360f3 | 670 | { |
db5360f3 ES |
671 | struct dir_entry *dir; |
672 | ||
673 | lazy_init_name_hash(istate); | |
674 | dir = find_dir_entry(istate, name, namelen); | |
41284eb0 DT |
675 | return dir && dir->nr; |
676 | } | |
db5360f3 | 677 | |
41284eb0 DT |
678 | void adjust_dirname_case(struct index_state *istate, char *name) |
679 | { | |
680 | const char *startPtr = name; | |
681 | const char *ptr = startPtr; | |
db5360f3 | 682 | |
41284eb0 DT |
683 | lazy_init_name_hash(istate); |
684 | while (*ptr) { | |
685 | while (*ptr && *ptr != '/') | |
686 | ptr++; | |
687 | ||
688 | if (*ptr == '/') { | |
689 | struct dir_entry *dir; | |
690 | ||
c95525e9 | 691 | dir = find_dir_entry(istate, name, ptr - name); |
41284eb0 DT |
692 | if (dir) { |
693 | memcpy((void *)startPtr, dir->name + (startPtr - name), ptr - startPtr); | |
c95525e9 | 694 | startPtr = ptr + 1; |
41284eb0 | 695 | } |
c95525e9 | 696 | ptr++; |
41284eb0 DT |
697 | } |
698 | } | |
db5360f3 ES |
699 | } |
700 | ||
701 | struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int icase) | |
96872bc2 | 702 | { |
96872bc2 LT |
703 | struct cache_entry *ce; |
704 | ||
705 | lazy_init_name_hash(istate); | |
96872bc2 | 706 | |
ab73a9d1 KB |
707 | ce = hashmap_get_from_hash(&istate->name_hash, |
708 | memihash(name, namelen), NULL); | |
96872bc2 | 709 | while (ce) { |
419a597f KB |
710 | if (same_name(ce, name, namelen, icase)) |
711 | return ce; | |
8b013788 | 712 | ce = hashmap_get_next(&istate->name_hash, ce); |
96872bc2 | 713 | } |
df292c79 | 714 | return NULL; |
96872bc2 | 715 | } |
2092678c | 716 | |
2092678c KB |
717 | void free_name_hash(struct index_state *istate) |
718 | { | |
719 | if (!istate->name_hash_initialized) | |
720 | return; | |
721 | istate->name_hash_initialized = 0; | |
2092678c | 722 | |
8b013788 | 723 | hashmap_free(&istate->name_hash, 0); |
e05881a4 | 724 | hashmap_free(&istate->dir_hash, 1); |
2092678c | 725 | } |