mirror of
https://github.com/yuzu-emu/unicorn.git
synced 2024-12-24 01:25:40 +00:00
394 lines
9.7 KiB
C
394 lines
9.7 KiB
C
/*
|
|
* Win32 implementation for mutex/cond/thread functions
|
|
*
|
|
* Copyright Red Hat, Inc. 2010
|
|
*
|
|
* Author:
|
|
* Paolo Bonzini <pbonzini@redhat.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2 or later.
|
|
* See the COPYING file in the top-level directory.
|
|
*
|
|
*/
|
|
#include "qemu-common.h"
|
|
#include "qemu/thread.h"
|
|
#include <process.h>
|
|
#include <assert.h>
|
|
#include <limits.h>
|
|
|
|
#include "uc_priv.h"
|
|
|
|
|
|
static void error_exit(int err, const char *msg)
|
|
{
|
|
char *pstr;
|
|
|
|
FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ALLOCATE_BUFFER,
|
|
NULL, err, 0, (LPTSTR)&pstr, 2, NULL);
|
|
fprintf(stderr, "qemu: %s: %s\n", msg, pstr);
|
|
LocalFree(pstr);
|
|
//abort();
|
|
}
|
|
|
|
void qemu_mutex_init(QemuMutex *mutex)
|
|
{
|
|
mutex->owner = 0;
|
|
InitializeCriticalSection(&mutex->lock);
|
|
}
|
|
|
|
void qemu_mutex_destroy(QemuMutex *mutex)
|
|
{
|
|
assert(mutex->owner == 0);
|
|
DeleteCriticalSection(&mutex->lock);
|
|
}
|
|
|
|
void qemu_mutex_lock(QemuMutex *mutex)
|
|
{
|
|
EnterCriticalSection(&mutex->lock);
|
|
|
|
/* Win32 CRITICAL_SECTIONs are recursive. Assert that we're not
|
|
* using them as such.
|
|
*/
|
|
assert(mutex->owner == 0);
|
|
mutex->owner = GetCurrentThreadId();
|
|
}
|
|
|
|
int qemu_mutex_trylock(QemuMutex *mutex)
|
|
{
|
|
int owned;
|
|
|
|
owned = TryEnterCriticalSection(&mutex->lock);
|
|
if (owned) {
|
|
assert(mutex->owner == 0);
|
|
mutex->owner = GetCurrentThreadId();
|
|
}
|
|
return !owned;
|
|
}
|
|
|
|
void qemu_mutex_unlock(QemuMutex *mutex)
|
|
{
|
|
assert(mutex->owner == GetCurrentThreadId());
|
|
mutex->owner = 0;
|
|
LeaveCriticalSection(&mutex->lock);
|
|
}
|
|
|
|
void qemu_cond_init(QemuCond *cond)
|
|
{
|
|
memset(cond, 0, sizeof(*cond));
|
|
|
|
cond->sema = CreateSemaphore(NULL, 0, LONG_MAX, NULL);
|
|
if (!cond->sema) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
cond->continue_event = CreateEvent(NULL, /* security */
|
|
FALSE, /* auto-reset */
|
|
FALSE, /* not signaled */
|
|
NULL); /* name */
|
|
if (!cond->continue_event) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
}
|
|
|
|
void qemu_cond_destroy(QemuCond *cond)
|
|
{
|
|
BOOL result;
|
|
result = CloseHandle(cond->continue_event);
|
|
if (!result) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
cond->continue_event = 0;
|
|
result = CloseHandle(cond->sema);
|
|
if (!result) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
cond->sema = 0;
|
|
}
|
|
|
|
void qemu_cond_signal(QemuCond *cond)
|
|
{
|
|
DWORD result;
|
|
|
|
/*
|
|
* Signal only when there are waiters. cond->waiters is
|
|
* incremented by pthread_cond_wait under the external lock,
|
|
* so we are safe about that.
|
|
*/
|
|
if (cond->waiters == 0) {
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Waiting threads decrement it outside the external lock, but
|
|
* only if another thread is executing pthread_cond_broadcast and
|
|
* has the mutex. So, it also cannot be decremented concurrently
|
|
* with this particular access.
|
|
*/
|
|
cond->target = cond->waiters - 1;
|
|
result = SignalObjectAndWait(cond->sema, cond->continue_event,
|
|
INFINITE, FALSE);
|
|
if (result == WAIT_ABANDONED || result == WAIT_FAILED) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
}
|
|
|
|
void qemu_cond_broadcast(QemuCond *cond)
|
|
{
|
|
BOOLEAN result;
|
|
/*
|
|
* As in pthread_cond_signal, access to cond->waiters and
|
|
* cond->target is locked via the external mutex.
|
|
*/
|
|
if (cond->waiters == 0) {
|
|
return;
|
|
}
|
|
|
|
cond->target = 0;
|
|
result = ReleaseSemaphore(cond->sema, cond->waiters, NULL);
|
|
if (!result) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
|
|
/*
|
|
* At this point all waiters continue. Each one takes its
|
|
* slice of the semaphore. Now it's our turn to wait: Since
|
|
* the external mutex is held, no thread can leave cond_wait,
|
|
* yet. For this reason, we can be sure that no thread gets
|
|
* a chance to eat *more* than one slice. OTOH, it means
|
|
* that the last waiter must send us a wake-up.
|
|
*/
|
|
WaitForSingleObject(cond->continue_event, INFINITE);
|
|
}
|
|
|
|
void qemu_cond_wait(QemuCond *cond, QemuMutex *mutex)
|
|
{
|
|
/*
|
|
* This access is protected under the mutex.
|
|
*/
|
|
cond->waiters++;
|
|
|
|
/*
|
|
* Unlock external mutex and wait for signal.
|
|
* NOTE: we've held mutex locked long enough to increment
|
|
* waiters count above, so there's no problem with
|
|
* leaving mutex unlocked before we wait on semaphore.
|
|
*/
|
|
qemu_mutex_unlock(mutex);
|
|
WaitForSingleObject(cond->sema, INFINITE);
|
|
|
|
/* Now waiters must rendez-vous with the signaling thread and
|
|
* let it continue. For cond_broadcast this has heavy contention
|
|
* and triggers thundering herd. So goes life.
|
|
*
|
|
* Decrease waiters count. The mutex is not taken, so we have
|
|
* to do this atomically.
|
|
*
|
|
* All waiters contend for the mutex at the end of this function
|
|
* until the signaling thread relinquishes it. To ensure
|
|
* each waiter consumes exactly one slice of the semaphore,
|
|
* the signaling thread stops until it is told by the last
|
|
* waiter that it can go on.
|
|
*/
|
|
if (InterlockedDecrement(&cond->waiters) == cond->target) {
|
|
SetEvent(cond->continue_event);
|
|
}
|
|
|
|
qemu_mutex_lock(mutex);
|
|
}
|
|
|
|
void qemu_sem_init(QemuSemaphore *sem, int init)
|
|
{
|
|
/* Manual reset. */
|
|
sem->sema = CreateSemaphore(NULL, init, LONG_MAX, NULL);
|
|
}
|
|
|
|
void qemu_sem_destroy(QemuSemaphore *sem)
|
|
{
|
|
CloseHandle(sem->sema);
|
|
}
|
|
|
|
void qemu_sem_post(QemuSemaphore *sem)
|
|
{
|
|
ReleaseSemaphore(sem->sema, 1, NULL);
|
|
}
|
|
|
|
int qemu_sem_timedwait(QemuSemaphore *sem, int ms)
|
|
{
|
|
int rc = WaitForSingleObject(sem->sema, ms);
|
|
if (rc == WAIT_OBJECT_0) {
|
|
return 0;
|
|
}
|
|
if (rc != WAIT_TIMEOUT) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
void qemu_sem_wait(QemuSemaphore *sem)
|
|
{
|
|
if (WaitForSingleObject(sem->sema, INFINITE) != WAIT_OBJECT_0) {
|
|
error_exit(GetLastError(), __func__);
|
|
}
|
|
}
|
|
|
|
void qemu_event_init(QemuEvent *ev, bool init)
|
|
{
|
|
/* Manual reset. */
|
|
ev->event = CreateEvent(NULL, TRUE, init, NULL);
|
|
}
|
|
|
|
void qemu_event_destroy(QemuEvent *ev)
|
|
{
|
|
CloseHandle(ev->event);
|
|
}
|
|
|
|
void qemu_event_set(QemuEvent *ev)
|
|
{
|
|
SetEvent(ev->event);
|
|
}
|
|
|
|
void qemu_event_reset(QemuEvent *ev)
|
|
{
|
|
ResetEvent(ev->event);
|
|
}
|
|
|
|
void qemu_event_wait(QemuEvent *ev)
|
|
{
|
|
WaitForSingleObject(ev->event, INFINITE);
|
|
}
|
|
|
|
struct QemuThreadData {
|
|
/* Passed to win32_start_routine. */
|
|
void *(*start_routine)(void *);
|
|
void *arg;
|
|
short mode;
|
|
|
|
/* Only used for joinable threads. */
|
|
bool exited;
|
|
void *ret;
|
|
CRITICAL_SECTION cs;
|
|
struct uc_struct *uc;
|
|
};
|
|
|
|
static unsigned __stdcall win32_start_routine(void *arg)
|
|
{
|
|
QemuThreadData *data = (QemuThreadData *) arg;
|
|
void *(*start_routine)(void *) = data->start_routine;
|
|
void *thread_arg = data->arg;
|
|
|
|
if (data->mode == QEMU_THREAD_DETACHED) {
|
|
g_free(data);
|
|
data = NULL;
|
|
}
|
|
qemu_thread_exit(data->uc, start_routine(thread_arg));
|
|
abort();
|
|
}
|
|
|
|
void qemu_thread_exit(struct uc_struct *uc, void *arg)
|
|
{
|
|
QemuThreadData *data = uc->qemu_thread_data;
|
|
|
|
if (data) {
|
|
assert(data->mode != QEMU_THREAD_DETACHED);
|
|
data->ret = arg;
|
|
EnterCriticalSection(&data->cs);
|
|
data->exited = true;
|
|
LeaveCriticalSection(&data->cs);
|
|
}
|
|
_endthreadex(0);
|
|
}
|
|
|
|
void *qemu_thread_join(QemuThread *thread)
|
|
{
|
|
QemuThreadData *data;
|
|
void *ret;
|
|
HANDLE handle;
|
|
|
|
data = thread->data;
|
|
if (!data) {
|
|
return NULL;
|
|
}
|
|
/*
|
|
* Because multiple copies of the QemuThread can exist via
|
|
* qemu_thread_get_self, we need to store a value that cannot
|
|
* leak there. The simplest, non racy way is to store the TID,
|
|
* discard the handle that _beginthreadex gives back, and
|
|
* get another copy of the handle here.
|
|
*/
|
|
handle = qemu_thread_get_handle(thread);
|
|
if (handle) {
|
|
WaitForSingleObject(handle, INFINITE);
|
|
CloseHandle(handle);
|
|
}
|
|
ret = data->ret;
|
|
assert(data->mode != QEMU_THREAD_DETACHED);
|
|
DeleteCriticalSection(&data->cs);
|
|
g_free(data);
|
|
return ret;
|
|
}
|
|
|
|
int qemu_thread_create(struct uc_struct *uc, QemuThread *thread, const char *name,
|
|
void *(*start_routine)(void *),
|
|
void *arg, int mode)
|
|
{
|
|
HANDLE hThread;
|
|
struct QemuThreadData *data;
|
|
|
|
data = g_malloc(sizeof *data);
|
|
data->start_routine = start_routine;
|
|
data->arg = arg;
|
|
data->mode = mode;
|
|
data->exited = false;
|
|
data->uc = uc;
|
|
|
|
uc->qemu_thread_data = data;
|
|
|
|
if (data->mode != QEMU_THREAD_DETACHED) {
|
|
InitializeCriticalSection(&data->cs);
|
|
}
|
|
|
|
hThread = (HANDLE) _beginthreadex(NULL, 0, win32_start_routine,
|
|
data, 0, &thread->tid);
|
|
if (!hThread) {
|
|
error_exit(GetLastError(), __func__);
|
|
return -1;
|
|
}
|
|
|
|
CloseHandle(hThread);
|
|
thread->data = (mode == QEMU_THREAD_DETACHED) ? NULL : data;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void qemu_thread_get_self(struct uc_struct *uc, QemuThread *thread)
|
|
{
|
|
thread->data = uc->qemu_thread_data;
|
|
thread->tid = GetCurrentThreadId();
|
|
}
|
|
|
|
HANDLE qemu_thread_get_handle(QemuThread *thread)
|
|
{
|
|
QemuThreadData *data;
|
|
HANDLE handle;
|
|
|
|
data = thread->data;
|
|
if (!data) {
|
|
return NULL;
|
|
}
|
|
|
|
assert(data->mode != QEMU_THREAD_DETACHED);
|
|
EnterCriticalSection(&data->cs);
|
|
if (!data->exited) {
|
|
handle = OpenThread(SYNCHRONIZE | THREAD_SUSPEND_RESUME, FALSE,
|
|
thread->tid);
|
|
} else {
|
|
handle = NULL;
|
|
}
|
|
LeaveCriticalSection(&data->cs);
|
|
return handle;
|
|
}
|
|
|
|
bool qemu_thread_is_self(QemuThread *thread)
|
|
{
|
|
return GetCurrentThreadId() == thread->tid;
|
|
}
|