1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
|
/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkOnce.h"
#include "SkThreadPool.h"
#include "Test.h"
#include "TestClassDef.h"
static void add_five(int* x) {
*x += 5;
}
DEF_TEST(SkOnce_Singlethreaded, r) {
int x = 0;
SK_DECLARE_STATIC_ONCE(once);
// No matter how many times we do this, x will be 5.
SkOnce(&once, add_five, &x);
SkOnce(&once, add_five, &x);
SkOnce(&once, add_five, &x);
SkOnce(&once, add_five, &x);
SkOnce(&once, add_five, &x);
REPORTER_ASSERT(r, 5 == x);
}
static void add_six(int* x) {
*x += 6;
}
class Racer : public SkRunnable {
public:
SkOnceFlag* once;
int* ptr;
virtual void run() SK_OVERRIDE {
SkOnce(once, add_six, ptr);
}
};
DEF_TEST(SkOnce_Multithreaded, r) {
const int kTasks = 16, kThreads = 4;
// Make a bunch of tasks that will race to be the first to add six to x.
Racer racers[kTasks];
SK_DECLARE_STATIC_ONCE(once);
int x = 0;
for (int i = 0; i < kTasks; i++) {
racers[i].once = &once;
racers[i].ptr = &x;
}
// Let them race.
SkThreadPool pool(kThreads);
for (int i = 0; i < kTasks; i++) {
pool.add(&racers[i]);
}
pool.wait();
// Only one should have done the +=.
REPORTER_ASSERT(r, 6 == x);
}
|