diff options
Diffstat (limited to 'preload-index.c')
| -rw-r--r-- | preload-index.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/preload-index.c b/preload-index.c new file mode 100644 index 0000000..ed6eaa4 --- /dev/null +++ b/preload-index.c @@ -0,0 +1,158 @@ +/* + * Copyright (C) 2008 Linus Torvalds + */ +#include "cache.h" +#include "pathspec.h" +#include "dir.h" +#include "fsmonitor.h" +#include "config.h" +#include "progress.h" +#include "thread-utils.h" +#include "repository.h" + +/* + * Mostly randomly chosen maximum thread counts: we + * cap the parallelism to 20 threads, and we want + * to have at least 500 lstat's per thread for it to + * be worth starting a thread. + */ +#define MAX_PARALLEL (20) +#define THREAD_COST (500) + +struct progress_data { + unsigned long n; + struct progress *progress; + pthread_mutex_t mutex; +}; + +struct thread_data { + pthread_t pthread; + struct index_state *index; + struct pathspec pathspec; + struct progress_data *progress; + int offset, nr; +}; + +static void *preload_thread(void *_data) +{ + int nr, last_nr; + struct thread_data *p = _data; + struct index_state *index = p->index; + struct cache_entry **cep = index->cache + p->offset; + struct cache_def cache = CACHE_DEF_INIT; + + nr = p->nr; + if (nr + p->offset > index->cache_nr) + nr = index->cache_nr - p->offset; + last_nr = nr; + + do { + struct cache_entry *ce = *cep++; + struct stat st; + + if (ce_stage(ce)) + continue; + if (S_ISGITLINK(ce->ce_mode)) + continue; + if (ce_uptodate(ce)) + continue; + if (ce_skip_worktree(ce)) + continue; + if (ce->ce_flags & CE_FSMONITOR_VALID) + continue; + if (p->progress && !(nr & 31)) { + struct progress_data *pd = p->progress; + + pthread_mutex_lock(&pd->mutex); + pd->n += last_nr - nr; + display_progress(pd->progress, pd->n); + pthread_mutex_unlock(&pd->mutex); + last_nr = nr; + } + if (!ce_path_match(index, ce, &p->pathspec, NULL)) + continue; + if (threaded_has_symlink_leading_path(&cache, ce->name, ce_namelen(ce))) + continue; + if (lstat(ce->name, &st)) + continue; + if (ie_match_stat(index, ce, &st, CE_MATCH_RACY_IS_DIRTY|CE_MATCH_IGNORE_FSMONITOR)) + continue; + ce_mark_uptodate(ce); + mark_fsmonitor_valid(index, ce); + } while (--nr > 0); + if (p->progress) { + struct progress_data *pd = p->progress; + + pthread_mutex_lock(&pd->mutex); + display_progress(pd->progress, pd->n + last_nr); + pthread_mutex_unlock(&pd->mutex); + } + cache_def_clear(&cache); + return NULL; +} + +void preload_index(struct index_state *index, + const struct pathspec *pathspec, + unsigned int refresh_flags) +{ + int threads, i, work, offset; + struct thread_data data[MAX_PARALLEL]; + struct progress_data pd; + + if (!HAVE_THREADS || !core_preload_index) + return; + + threads = index->cache_nr / THREAD_COST; + if ((index->cache_nr > 1) && (threads < 2) && git_env_bool("GIT_TEST_PRELOAD_INDEX", 0)) + threads = 2; + if (threads < 2) + return; + trace_performance_enter(); + if (threads > MAX_PARALLEL) + threads = MAX_PARALLEL; + offset = 0; + work = DIV_ROUND_UP(index->cache_nr, threads); + memset(&data, 0, sizeof(data)); + + memset(&pd, 0, sizeof(pd)); + if (refresh_flags & REFRESH_PROGRESS && isatty(2)) { + pd.progress = start_delayed_progress(_("Refreshing index"), index->cache_nr); + pthread_mutex_init(&pd.mutex, NULL); + } + + for (i = 0; i < threads; i++) { + struct thread_data *p = data+i; + int err; + + p->index = index; + if (pathspec) + copy_pathspec(&p->pathspec, pathspec); + p->offset = offset; + p->nr = work; + if (pd.progress) + p->progress = &pd; + offset += work; + err = pthread_create(&p->pthread, NULL, preload_thread, p); + + if (err) + die(_("unable to create threaded lstat: %s"), strerror(err)); + } + for (i = 0; i < threads; i++) { + struct thread_data *p = data+i; + if (pthread_join(p->pthread, NULL)) + die("unable to join threaded lstat"); + } + stop_progress(&pd.progress); + + trace_performance_leave("preload index"); +} + +int repo_read_index_preload(struct repository *repo, + const struct pathspec *pathspec, + unsigned int refresh_flags) +{ + int retval = repo_read_index(repo); + + preload_index(repo->index, pathspec, refresh_flags); + return retval; +} |