2 * Copyright (C) 2008 Linus Torvalds
11 static void preload_index(struct index_state *index,
12 const struct pathspec *pathspec)
21 * Mostly randomly chosen maximum thread counts: we
22 * cap the parallelism to 20 threads, and we want
23 * to have at least 500 lstat's per thread for it to
24 * be worth starting a thread.
26 #define MAX_PARALLEL (20)
27 #define THREAD_COST (500)
31 struct index_state *index;
32 struct pathspec pathspec;
36 static void *preload_thread(void *_data)
39 struct thread_data *p = _data;
40 struct index_state *index = p->index;
41 struct cache_entry **cep = index->cache + p->offset;
42 struct cache_def cache = CACHE_DEF_INIT;
45 if (nr + p->offset > index->cache_nr)
46 nr = index->cache_nr - p->offset;
49 struct cache_entry *ce = *cep++;
54 if (S_ISGITLINK(ce->ce_mode))
58 if (ce_skip_worktree(ce))
60 if (ce->ce_flags & CE_FSMONITOR_VALID)
62 if (!ce_path_match(index, ce, &p->pathspec, NULL))
64 if (threaded_has_symlink_leading_path(&cache, ce->name, ce_namelen(ce)))
66 if (lstat(ce->name, &st))
68 if (ie_match_stat(index, ce, &st, CE_MATCH_RACY_IS_DIRTY|CE_MATCH_IGNORE_FSMONITOR))
71 mark_fsmonitor_valid(ce);
73 cache_def_clear(&cache);
77 static void preload_index(struct index_state *index,
78 const struct pathspec *pathspec)
80 int threads, i, work, offset;
81 struct thread_data data[MAX_PARALLEL];
83 if (!core_preload_index)
86 threads = index->cache_nr / THREAD_COST;
87 if ((index->cache_nr > 1) && (threads < 2) && git_env_bool("GIT_TEST_PRELOAD_INDEX", 0))
91 trace_performance_enter();
92 if (threads > MAX_PARALLEL)
93 threads = MAX_PARALLEL;
95 work = DIV_ROUND_UP(index->cache_nr, threads);
96 memset(&data, 0, sizeof(data));
97 for (i = 0; i < threads; i++) {
98 struct thread_data *p = data+i;
101 copy_pathspec(&p->pathspec, pathspec);
105 if (pthread_create(&p->pthread, NULL, preload_thread, p))
106 die("unable to create threaded lstat");
108 for (i = 0; i < threads; i++) {
109 struct thread_data *p = data+i;
110 if (pthread_join(p->pthread, NULL))
111 die("unable to join threaded lstat");
113 trace_performance_leave("preload index");
117 int read_index_preload(struct index_state *index,
118 const struct pathspec *pathspec)
120 int retval = read_index(index);
122 preload_index(index, pathspec);