mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-07-06 11:18:30 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Use *NSYNC for POSIX threads locking APIs

Browse source 
Condition variables, barriers, and r/w locks now work very well.
This commit is contained in:
Justine Tunney 2022-09-11 11:02:07 -07:00
parent 3de35e196c
commit b5cb71ab84
No known key found for this signature in database
GPG key ID: BE714B4575D6E328
197 changed files with 3734 additions and 3817 deletions
Download patch file Download diff file Expand all files Collapse all files

56
third_party/nsync/waiter_per_thread.c vendored Normal file
View file

@ -0,0 +1,56 @@
/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8 -*-│
│vi: set et ft=c ts=8 tw=8 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2016 Google Inc. │
│ │
│ Licensed under the Apache License, Version 2.0 (the "License"); │
│ you may not use this file except in compliance with the License. │
│ You may obtain a copy of the License at │
│ │
│ http://www.apache.org/licenses/LICENSE-2.0 │
│ │
│ Unless required by applicable law or agreed to in writing, software │
│ distributed under the License is distributed on an "AS IS" BASIS, │
│ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. │
│ See the License for the specific language governing permissions and │
│ limitations under the License. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "third_party/nsync/atomic.h"
#include "third_party/nsync/atomic.internal.h"
#include "third_party/nsync/common.internal.h"
#include "libc/thread/thread.h"
asm(".ident\t\"\\n\\n\
*NSYNC (Apache 2.0)\\n\
Copyright 2016 Google, Inc.\\n\
https://github.com/google/nsync\"");
// clang-format off
static pthread_key_t waiter_key;
static nsync_atomic_uint32_ pt_once;
static void do_once (nsync_atomic_uint32_ *ponce, void (*dest) (void *)) {
uint32_t o = ATM_LOAD_ACQ (ponce);
if (o != 2) {
while (o == 0 && !ATM_CAS_ACQ (ponce, 0, 1)) {
o = ATM_LOAD (ponce);
}
if (o == 0) {
pthread_key_create (&waiter_key, dest);
ATM_STORE_REL (ponce, 2);
}
while (ATM_LOAD_ACQ (ponce) != 2) {
nsync_yield_ ();
}
}
}
void *nsync_per_thread_waiter_ (void (*dest) (void *)) {
do_once (&pt_once, dest);
return (pthread_getspecific (waiter_key));
}
void nsync_set_per_thread_waiter_ (void *v, void (*dest) (void *)) {
do_once (&pt_once, dest);
pthread_setspecific (waiter_key, v);
}