git/preload-index.c
Nguyễn Thái Ngọc Duy 6d2df284e7 dir.c: remove an implicit dependency on the_index in pathspec code
Make the match_patchspec API and friends take an index_state instead
of assuming the_index in dir.c. All external call sites are converted
blindly to keep the patch simple and retain current behavior.
Individual call sites may receive further updates to use the right
index instead of the_index.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 14:14:42 -07:00

124 lines
2.8 KiB
C

/*
* Copyright (C) 2008 Linus Torvalds
*/
#include "cache.h"
#include "pathspec.h"
#include "dir.h"
#include "fsmonitor.h"
#ifdef NO_PTHREADS
static void preload_index(struct index_state *index,
const struct pathspec *pathspec)
{
; /* nothing */
}
#else
#include <pthread.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 thread_data {
pthread_t pthread;
struct index_state *index;
struct pathspec pathspec;
int offset, nr;
};
static void *preload_thread(void *_data)
{
int 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;
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 (!ce_path_match(&the_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(ce);
} while (--nr > 0);
cache_def_clear(&cache);
return NULL;
}
static void preload_index(struct index_state *index,
const struct pathspec *pathspec)
{
int threads, i, work, offset;
struct thread_data data[MAX_PARALLEL];
uint64_t start = getnanotime();
if (!core_preload_index)
return;
threads = index->cache_nr / THREAD_COST;
if ((index->cache_nr > 1) && (threads < 2) && getenv("GIT_FORCE_PRELOAD_TEST"))
threads = 2;
if (threads < 2)
return;
if (threads > MAX_PARALLEL)
threads = MAX_PARALLEL;
offset = 0;
work = DIV_ROUND_UP(index->cache_nr, threads);
memset(&data, 0, sizeof(data));
for (i = 0; i < threads; i++) {
struct thread_data *p = data+i;
p->index = index;
if (pathspec)
copy_pathspec(&p->pathspec, pathspec);
p->offset = offset;
p->nr = work;
offset += work;
if (pthread_create(&p->pthread, NULL, preload_thread, p))
die("unable to create threaded lstat");
}
for (i = 0; i < threads; i++) {
struct thread_data *p = data+i;
if (pthread_join(p->pthread, NULL))
die("unable to join threaded lstat");
}
trace_performance_since(start, "preload index");
}
#endif
int read_index_preload(struct index_state *index,
const struct pathspec *pathspec)
{
int retval = read_index(index);
preload_index(index, pathspec);
return retval;
}