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
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
//===------- state-queue.cu - NVPTX OpenMP GPU State Queue ------- CUDA -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.txt for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the implementation of a queue to hand out OpenMP state
// objects to teams of one or more kernels.
//
// Reference:
// Thomas R.W. Scogland and Wu-chun Feng. 2015.
// Design and Evaluation of Scalable Concurrent Queues for Many-Core
// Architectures. International Conference on Performance Engineering.
//
//===----------------------------------------------------------------------===//
#include "state-queue.h"
template <typename ElementType, uint32_t SIZE>
INLINE uint32_t omptarget_nvptx_Queue<ElementType, SIZE>::ENQUEUE_TICKET() {
return atomicAdd((unsigned int *)&tail, 1);
}
template <typename ElementType, uint32_t SIZE>
INLINE uint32_t omptarget_nvptx_Queue<ElementType, SIZE>::DEQUEUE_TICKET() {
return atomicAdd((unsigned int *)&head, 1);
}
template <typename ElementType, uint32_t SIZE>
INLINE uint32_t omptarget_nvptx_Queue<ElementType, SIZE>::ID(uint32_t ticket) {
return (ticket / SIZE) * 2;
}
template <typename ElementType, uint32_t SIZE>
INLINE bool omptarget_nvptx_Queue<ElementType, SIZE>::IsServing(uint32_t slot,
uint32_t id) {
return atomicAdd((unsigned int *)&ids[slot], 0) == id;
}
template <typename ElementType, uint32_t SIZE>
INLINE void
omptarget_nvptx_Queue<ElementType, SIZE>::PushElement(uint32_t slot,
ElementType *element) {
atomicExch((unsigned long long *)&elementQueue[slot],
(unsigned long long)element);
}
template <typename ElementType, uint32_t SIZE>
INLINE ElementType *
omptarget_nvptx_Queue<ElementType, SIZE>::PopElement(uint32_t slot) {
return (ElementType *)atomicAdd((unsigned long long *)&elementQueue[slot],
(unsigned long long)0);
}
template <typename ElementType, uint32_t SIZE>
INLINE void omptarget_nvptx_Queue<ElementType, SIZE>::DoneServing(uint32_t slot,
uint32_t id) {
atomicExch((unsigned int *)&ids[slot], (id + 1) % MAX_ID);
}
template <typename ElementType, uint32_t SIZE>
INLINE void
omptarget_nvptx_Queue<ElementType, SIZE>::Enqueue(ElementType *element) {
uint32_t ticket = ENQUEUE_TICKET();
uint32_t slot = ticket % SIZE;
uint32_t id = ID(ticket) + 1;
while (!IsServing(slot, id))
;
PushElement(slot, element);
DoneServing(slot, id);
}
template <typename ElementType, uint32_t SIZE>
INLINE ElementType *omptarget_nvptx_Queue<ElementType, SIZE>::Dequeue() {
uint32_t ticket = DEQUEUE_TICKET();
uint32_t slot = ticket % SIZE;
uint32_t id = ID(ticket);
while (!IsServing(slot, id))
;
ElementType *element = PopElement(slot);
// This is to populate the queue because of the lack of GPU constructors.
if (element == 0)
element = &elements[slot];
DoneServing(slot, id);
return element;
}
|
