CUTLASS: semaphore.h Source File

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semaphore.h
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29 #pragma once
30
31 #include "cutlass/cutlass.h"
32
33 #include "cutlass/aligned_buffer.h"
34 #include "cutlass/array.h"
35
36 #include "cutlass/numeric_types.h"
37 #include "cutlass/matrix_shape.h"
38
39 #include "cutlass/gemm/gemm.h"
40
42
43 namespace cutlass {
44
46
48 class Semaphore {
49 public:
50
51 int *lock;
52 bool wait_thread;
53 int state;
54
55 public:
56
58 CUTLASS_HOST_DEVICE
59 Semaphore(int *lock_, int thread_id):
60 lock(lock_),
61 wait_thread(thread_id < 0 || thread_id == 0),
62 state(-1) {
63
64 }
65
67 CUTLASS_DEVICE
68 void fetch() {
69
70 asm volatile ("ld.global.cg.s32 %0, [%1];\n" : "=r"(state) : "l"(lock));
71 }
72
74 CUTLASS_DEVICE
75 int get_state() const {
76 return state;
77 }
78
80 CUTLASS_DEVICE
81 void wait(int status = 0) {
82
83 if (wait_thread) {
84 while (state != status) {
85
86 fetch();
87
88 __syncwarp(0x01);
89
90 };
91 }
92
93 __syncthreads();
94 }
95
97 CUTLASS_DEVICE
98 void release(int status = 0) {
99 __syncthreads();
100
101 if (wait_thread) {
102
103 asm volatile ("st.global.cg.s32 [%0], %1;\n" : : "l"(lock), "r"(status));
104 }
105 }
106 };
107
109
110 } // namespace cutlass
111
cutlass
Definition: aligned_buffer.h:35
gemm.h
Defines common types used for all GEMM-like operators.
cutlass::Semaphore::Semaphore
CUTLASS_HOST_DEVICE Semaphore(int *lock_, int thread_id)
Implements a semaphore to wait for a flag to reach a given value.
Definition: semaphore.h:59
cutlass::Semaphore::fetch
CUTLASS_DEVICE void fetch()
Permit fetching the synchronization mechanism early.
Definition: semaphore.h:68
array.h
Statically sized array of elements that accommodates all CUTLASS-supported numeric types and is safe ...
matrix_shape.h
Defines a Shape template for matrix tiles.
cutlass::Semaphore::get_state
CUTLASS_DEVICE int get_state() const
Gets the internal state.
Definition: semaphore.h:75
cutlass::Semaphore::wait_thread
bool wait_thread
Definition: semaphore.h:52
aligned_buffer.h
AlignedBuffer is a container for trivially copyable elements suitable for use in unions and shared me...
CUTLASS_HOST_DEVICE
#define CUTLASS_HOST_DEVICE
Definition: cutlass.h:89
numeric_types.h
Top-level include for all CUTLASS numeric types.
cutlass::Semaphore
CTA-wide semaphore for inter-CTA synchronization.
Definition: semaphore.h:48
cutlass::Semaphore::release
CUTLASS_DEVICE void release(int status=0)
Updates the lock with the given result.
Definition: semaphore.h:98
cutlass::Semaphore::wait
CUTLASS_DEVICE void wait(int status=0)
Waits until the semaphore is equal to the given value.
Definition: semaphore.h:81
cutlass.h
Basic include for CUTLASS.
cutlass::Semaphore::state
int state
Definition: semaphore.h:53
cutlass::Semaphore::lock
int * lock
Definition: semaphore.h:51