| 1 | /* |
| 2 | * Copyright (C) 2008 Linus Torvalds |
| 3 | */ |
| 4 | |
| 5 | #define DISABLE_SIGN_COMPARE_WARNINGS |
| 6 | |
| 7 | #include "git-compat-util.h" |
| 8 | #include "pathspec.h" |
| 9 | #include "dir.h" |
| 10 | #include "environment.h" |
| 11 | #include "fsmonitor.h" |
| 12 | #include "gettext.h" |
| 13 | #include "parse.h" |
| 14 | #include "preload-index.h" |
| 15 | #include "progress.h" |
| 16 | #include "read-cache.h" |
| 17 | #include "thread-utils.h" |
| 18 | #include "repository.h" |
| 19 | #include "symlinks.h" |
| 20 | #include "trace2.h" |
| 21 | #include "config.h" |
| 22 | |
| 23 | /* |
| 24 | * Mostly randomly chosen maximum thread counts: we |
| 25 | * cap the parallelism to 20 threads, and we want |
| 26 | * to have at least 500 lstat's per thread for it to |
| 27 | * be worth starting a thread. |
| 28 | */ |
| 29 | #define MAX_PARALLEL (20) |
| 30 | #define THREAD_COST (500) |
| 31 | |
| 32 | struct progress_data { |
| 33 | unsigned long n; |
| 34 | struct progress *progress; |
| 35 | pthread_mutex_t mutex; |
| 36 | }; |
| 37 | |
| 38 | struct thread_data { |
| 39 | pthread_t pthread; |
| 40 | struct index_state *index; |
| 41 | struct pathspec pathspec; |
| 42 | struct progress_data *progress; |
| 43 | int offset, nr; |
| 44 | int t2_nr_lstat; |
| 45 | }; |
| 46 | |
| 47 | static void *preload_thread(void *_data) |
| 48 | { |
| 49 | int nr, last_nr; |
| 50 | struct thread_data *p = _data; |
| 51 | struct index_state *index = p->index; |
| 52 | struct cache_entry **cep = index->cache + p->offset; |
| 53 | struct cache_def cache = CACHE_DEF_INIT; |
| 54 | |
| 55 | nr = p->nr; |
| 56 | if (nr + p->offset > index->cache_nr) |
| 57 | nr = index->cache_nr - p->offset; |
| 58 | last_nr = nr; |
| 59 | |
| 60 | do { |
| 61 | struct cache_entry *ce = *cep++; |
| 62 | struct stat st; |
| 63 | |
| 64 | if (ce_stage(ce)) |
| 65 | continue; |
| 66 | if (S_ISGITLINK(ce->ce_mode)) |
| 67 | continue; |
| 68 | if (ce_uptodate(ce)) |
| 69 | continue; |
| 70 | if (ce_skip_worktree(ce)) |
| 71 | continue; |
| 72 | if (ce->ce_flags & CE_FSMONITOR_VALID) |
| 73 | continue; |
| 74 | if (p->progress && !(nr & 31)) { |
| 75 | struct progress_data *pd = p->progress; |
| 76 | |
| 77 | pthread_mutex_lock(&pd->mutex); |
| 78 | pd->n += last_nr - nr; |
| 79 | display_progress(pd->progress, pd->n); |
| 80 | pthread_mutex_unlock(&pd->mutex); |
| 81 | last_nr = nr; |
| 82 | } |
| 83 | if (!ce_path_match(index, ce, &p->pathspec, NULL)) |
| 84 | continue; |
| 85 | if (threaded_has_symlink_leading_path(&cache, ce->name, ce_namelen(ce))) |
| 86 | continue; |
| 87 | p->t2_nr_lstat++; |
| 88 | if (lstat(ce->name, &st)) |
| 89 | continue; |
| 90 | if (ie_match_stat(index, ce, &st, CE_MATCH_RACY_IS_DIRTY|CE_MATCH_IGNORE_FSMONITOR)) |
| 91 | continue; |
| 92 | ce_mark_uptodate(ce); |
| 93 | mark_fsmonitor_valid(index, ce); |
| 94 | } while (--nr > 0); |
| 95 | if (p->progress) { |
| 96 | struct progress_data *pd = p->progress; |
| 97 | |
| 98 | pthread_mutex_lock(&pd->mutex); |
| 99 | display_progress(pd->progress, pd->n + last_nr); |
| 100 | pthread_mutex_unlock(&pd->mutex); |
| 101 | } |
| 102 | cache_def_clear(&cache); |
| 103 | return NULL; |
| 104 | } |
| 105 | |
| 106 | void preload_index(struct index_state *index, |
| 107 | const struct pathspec *pathspec, |
| 108 | unsigned int refresh_flags) |
| 109 | { |
| 110 | int threads, i, work, offset; |
| 111 | struct thread_data data[MAX_PARALLEL]; |
| 112 | struct progress_data pd; |
| 113 | int t2_sum_lstat = 0; |
| 114 | int core_preload_index = 1; |
| 115 | |
| 116 | repo_config_get_bool(index->repo, "core.preloadindex", &core_preload_index); |
| 117 | |
| 118 | if (!HAVE_THREADS || !core_preload_index) |
| 119 | return; |
| 120 | |
| 121 | threads = index->cache_nr / THREAD_COST; |
| 122 | if ((index->cache_nr > 1) && (threads < 2) && git_env_bool("GIT_TEST_PRELOAD_INDEX", 0)) |
| 123 | threads = 2; |
| 124 | if (threads < 2) |
| 125 | return; |
| 126 | |
| 127 | trace2_region_enter("index", "preload", NULL); |
| 128 | |
| 129 | trace_performance_enter(); |
| 130 | if (threads > MAX_PARALLEL) |
| 131 | threads = MAX_PARALLEL; |
| 132 | offset = 0; |
| 133 | work = DIV_ROUND_UP(index->cache_nr, threads); |
| 134 | memset(&data, 0, sizeof(data)); |
| 135 | |
| 136 | memset(&pd, 0, sizeof(pd)); |
| 137 | if (refresh_flags & REFRESH_PROGRESS && isatty(2)) { |
| 138 | pd.progress = start_delayed_progress(index->repo, |
| 139 | _("Refreshing index"), |
| 140 | index->cache_nr); |
| 141 | pthread_mutex_init(&pd.mutex, NULL); |
| 142 | } |
| 143 | |
| 144 | for (i = 0; i < threads; i++) { |
| 145 | struct thread_data *p = data+i; |
| 146 | int err; |
| 147 | |
| 148 | p->index = index; |
| 149 | if (pathspec) |
| 150 | copy_pathspec(&p->pathspec, pathspec); |
| 151 | p->offset = offset; |
| 152 | p->nr = work; |
| 153 | if (pd.progress) |
| 154 | p->progress = &pd; |
| 155 | offset += work; |
| 156 | err = pthread_create(&p->pthread, NULL, preload_thread, p); |
| 157 | |
| 158 | if (err) |
| 159 | die(_("unable to create threaded lstat: %s"), strerror(err)); |
| 160 | } |
| 161 | for (i = 0; i < threads; i++) { |
| 162 | struct thread_data *p = data+i; |
| 163 | if (pthread_join(p->pthread, NULL)) |
| 164 | die("unable to join threaded lstat"); |
| 165 | t2_sum_lstat += p->t2_nr_lstat; |
| 166 | } |
| 167 | stop_progress(&pd.progress); |
| 168 | |
| 169 | if (pathspec) { |
| 170 | /* earlier we made deep copies for each thread to work with */ |
| 171 | for (i = 0; i < threads; i++) |
| 172 | clear_pathspec(&data[i].pathspec); |
| 173 | } |
| 174 | |
| 175 | trace_performance_leave("preload index"); |
| 176 | |
| 177 | trace2_data_intmax("index", NULL, "preload/sum_lstat", t2_sum_lstat); |
| 178 | trace2_region_leave("index", "preload", NULL); |
| 179 | } |
| 180 | |
| 181 | int repo_read_index_preload(struct repository *repo, |
| 182 | const struct pathspec *pathspec, |
| 183 | unsigned int refresh_flags) |
| 184 | { |
| 185 | int retval = repo_read_index(repo); |
| 186 | |
| 187 | preload_index(repo->index, pathspec, refresh_flags); |
| 188 | return retval; |
| 189 | } |