skia2/include/private/GrSingleOwner.h
joshualitt 1de610a528 Create debug only SkSingleOwner
This is so Gpu code can guard against improper multithreaded usage in
debug builds

TBR=bsalomon@google.com
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1555953004

Review URL: https://codereview.chromium.org/1555953004
2016-01-06 08:26:09 -08:00

53 lines
1.2 KiB
C++

/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrSingleOwner_DEFINED
#define GrSingleOwner_DEFINED
#include "SkTypes.h"
#ifdef SK_DEBUG
#include "SkMutex.h"
#include "SkThreadID.h"
// This is a debug tool to verify an object is only being used from one thread at a time.
class GrSingleOwner {
public:
GrSingleOwner() : fOwner(kIllegalThreadID), fReentranceCount(0) {}
struct AutoEnforce {
AutoEnforce(GrSingleOwner* so) : fSO(so) { fSO->enter(); }
~AutoEnforce() { fSO->exit(); }
GrSingleOwner* fSO;
};
private:
void enter() {
SkAutoMutexAcquire lock(fMutex);
SkThreadID self = SkGetThreadID();
SkASSERT(fOwner == self || fOwner == kIllegalThreadID);
fReentranceCount++;
fOwner = self;
}
void exit() {
SkAutoMutexAcquire lock(fMutex);
fReentranceCount--;
if (fReentranceCount == 0) {
fOwner = kIllegalThreadID;
}
}
SkMutex fMutex;
SkThreadID fOwner; // guarded by fMutex
int fReentranceCount; // guarded by fMutex
};
#endif
#endif