Updated MSA file for EBC.
[mirror_edk2.git] / MdePkg / Library / BaseLib / SynchronizationMsc.c
CommitLineData
878ddf1f 1/** @file\r
2 Implementation of synchronization functions.\r
3\r
ef7baf58 4 Copyright (c) 2006 - 2007, Intel Corporation<BR>\r
878ddf1f 5 All rights reserved. This program and the accompanying materials\r
6 are licensed and made available under the terms and conditions of the BSD License\r
7 which accompanies this distribution. The full text of the license may be found at\r
8 http://opensource.org/licenses/bsd-license.php\r
9\r
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
12\r
ef7baf58 13 Module Name: SynchronizationMsc.c\r
878ddf1f 14\r
15**/\r
16\r
58251024 17#include "BaseLibInternals.h"\r
18\r
eb9603a0 19//\r
ef7baf58 20// Microsoft Visual Studio 7.1 Function Prototypes for read write barrier Intrinsics\r
eb9603a0 21//\r
ef7baf58 22void _ReadWriteBarrier (void);\r
23#pragma intrinsic(_ReadWriteBarrier)\r
24\r
25\r
46dd23b8 26#define SPIN_LOCK_RELEASED ((UINTN) 1)\r
27#define SPIN_LOCK_ACQUIRED ((UINTN) 2)\r
878ddf1f 28\r
878ddf1f 29/**\r
30 Retrieves the architecture specific spin lock alignment requirements for\r
31 optimal spin lock performance.\r
32\r
33 This function retrieves the spin lock alignment requirements for optimal\r
34 performance on a given CPU architecture. The spin lock alignment must be a\r
35 power of two and is returned by this function. If there are no alignment\r
36 requirements, then 1 must be returned. The spin lock synchronization\r
37 functions must function correctly if the spin lock size and alignment values\r
38 returned by this function are not used at all. These values are hints to the\r
39 consumers of the spin lock synchronization functions to obtain optimal spin\r
40 lock performance.\r
41\r
42 @return The architecture specific spin lock alignment.\r
43\r
44**/\r
45UINTN\r
46EFIAPI\r
47GetSpinLockProperties (\r
48 VOID\r
49 )\r
50{\r
51 // @bug May use a PCD entry to determine this alignment.\r
52 return 32;\r
53}\r
54\r
55/**\r
56 Initializes a spin lock to the released state and returns the spin lock.\r
57\r
58 This function initializes the spin lock specified by SpinLock to the released\r
59 state, and returns SpinLock. Optimal performance can be achieved by calling\r
60 GetSpinLockProperties() to determine the size and alignment requirements for\r
61 SpinLock.\r
62\r
63 If SpinLock is NULL, then ASSERT().\r
64\r
65 @param SpinLock A pointer to the spin lock to initialize to the released\r
66 state.\r
67\r
68 @return SpinLock\r
69\r
70**/\r
71SPIN_LOCK *\r
72EFIAPI\r
73InitializeSpinLock (\r
74 OUT SPIN_LOCK *SpinLock\r
75 )\r
76{\r
77 ASSERT (SpinLock != NULL);\r
ef7baf58 78\r
79 _ReadWriteBarrier();\r
27787243 80 *SpinLock = SPIN_LOCK_RELEASED;\r
ef7baf58 81 _ReadWriteBarrier();\r
82\r
878ddf1f 83 return SpinLock;\r
84}\r
85\r
86/**\r
87 Waits until a spin lock can be placed in the acquired state.\r
88\r
89 This function checks the state of the spin lock specified by SpinLock. If\r
90 SpinLock is in the released state, then this function places SpinLock in the\r
91 acquired state and returns SpinLock. Otherwise, this function waits\r
92 indefinitely for the spin lock to be released, and then places it in the\r
93 acquired state and returns SpinLock. All state transitions of SpinLock must\r
94 be performed using MP safe mechanisms.\r
95\r
96 If SpinLock is NULL, then ASSERT().\r
97 If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().\r
98 If PcdSpinLockTimeout is not zero, and SpinLock is can not be acquired in\r
99 PcdSpinLockTimeout microseconds, then ASSERT().\r
100\r
101 @param SpinLock A pointer to the spin lock to place in the acquired state.\r
102\r
103 @return SpinLock\r
104\r
105**/\r
106SPIN_LOCK *\r
107EFIAPI\r
108AcquireSpinLock (\r
109 IN OUT SPIN_LOCK *SpinLock\r
110 )\r
111{\r
112 UINT64 Tick;\r
113 UINT64 Start, End;\r
114 UINT64 Timeout;\r
115\r
116 Tick = 0;\r
117 Start = 0;\r
118 End = 0;\r
dc530c7b 119 if (PcdGet32 (PcdSpinLockTimeout) > 0) {\r
878ddf1f 120 Tick = GetPerformanceCounter ();\r
121 Timeout = DivU64x32 (\r
122 MultU64x32 (\r
123 GetPerformanceCounterProperties (&Start, &End),\r
dc530c7b 124 PcdGet32 (PcdSpinLockTimeout)\r
878ddf1f 125 ),\r
126 1000000\r
127 );\r
128 if (Start < End) {\r
129 Tick += Timeout;\r
130 } else {\r
131 Tick -= Timeout;\r
132 }\r
133 }\r
134\r
135 while (!AcquireSpinLockOrFail (SpinLock)) {\r
136 CpuPause ();\r
137 ASSERT ((Start < End) ^ (Tick <= GetPerformanceCounter ()));\r
138 }\r
139 return SpinLock;\r
140}\r
141\r
142/**\r
143 Attempts to place a spin lock in the acquired state.\r
144\r
145 This function checks the state of the spin lock specified by SpinLock. If\r
146 SpinLock is in the released state, then this function places SpinLock in the\r
147 acquired state and returns TRUE. Otherwise, FALSE is returned. All state\r
148 transitions of SpinLock must be performed using MP safe mechanisms.\r
149\r
150 If SpinLock is NULL, then ASSERT().\r
151 If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().\r
152\r
153 @param SpinLock A pointer to the spin lock to place in the acquired state.\r
154\r
155 @retval TRUE SpinLock was placed in the acquired state.\r
156 @retval FALSE SpinLock could not be acquired.\r
157\r
158**/\r
159BOOLEAN\r
160EFIAPI\r
161AcquireSpinLockOrFail (\r
162 IN OUT SPIN_LOCK *SpinLock\r
163 )\r
164{\r
a4e9aab9 165 SPIN_LOCK LockValue;\r
166 VOID *Result;\r
ef7baf58 167 \r
878ddf1f 168 ASSERT (SpinLock != NULL);\r
a4e9aab9 169\r
170 LockValue = *SpinLock;\r
171 ASSERT (LockValue == SPIN_LOCK_ACQUIRED || LockValue == SPIN_LOCK_RELEASED);\r
c9708ddd 172\r
ef7baf58 173 _ReadWriteBarrier ();\r
174 Result = InterlockedCompareExchangePointer (\r
878ddf1f 175 (VOID**)SpinLock,\r
176 (VOID*)SPIN_LOCK_RELEASED,\r
177 (VOID*)SPIN_LOCK_ACQUIRED\r
878ddf1f 178 );\r
ef7baf58 179\r
180 _ReadWriteBarrier ();\r
181 return (BOOLEAN) (Result == (VOID*) SPIN_LOCK_RELEASED);\r
878ddf1f 182}\r
183\r
184/**\r
185 Releases a spin lock.\r
186\r
187 This function places the spin lock specified by SpinLock in the release state\r
188 and returns SpinLock.\r
189\r
190 If SpinLock is NULL, then ASSERT().\r
191 If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().\r
192\r
193 @param SpinLock A pointer to the spin lock to release.\r
194\r
195 @return SpinLock\r
196\r
197**/\r
198SPIN_LOCK *\r
199EFIAPI\r
200ReleaseSpinLock (\r
201 IN OUT SPIN_LOCK *SpinLock\r
202 )\r
203{\r
a4e9aab9 204 SPIN_LOCK LockValue;\r
205\r
878ddf1f 206 ASSERT (SpinLock != NULL);\r
a4e9aab9 207\r
208 LockValue = *SpinLock;\r
209 ASSERT (LockValue == SPIN_LOCK_ACQUIRED || LockValue == SPIN_LOCK_RELEASED);\r
c9708ddd 210\r
ef7baf58 211 _ReadWriteBarrier ();\r
27787243 212 *SpinLock = SPIN_LOCK_RELEASED;\r
ef7baf58 213 _ReadWriteBarrier ();\r
214\r
878ddf1f 215 return SpinLock;\r
216}\r
217\r
218/**\r
219 Performs an atomic increment of an 32-bit unsigned integer.\r
220\r
221 Performs an atomic increment of the 32-bit unsigned integer specified by\r
222 Value and returns the incremented value. The increment operation must be\r
223 performed using MP safe mechanisms. The state of the return value is not\r
224 guaranteed to be MP safe.\r
225\r
226 If Value is NULL, then ASSERT().\r
227\r
228 @param Value A pointer to the 32-bit value to increment.\r
229\r
230 @return The incremented value.\r
231\r
232**/\r
233UINT32\r
234EFIAPI\r
235InterlockedIncrement (\r
236 IN UINT32 *Value\r
237 )\r
238{\r
239 ASSERT (Value != NULL);\r
240 return InternalSyncIncrement (Value);\r
241}\r
242\r
243/**\r
244 Performs an atomic decrement of an 32-bit unsigned integer.\r
245\r
246 Performs an atomic decrement of the 32-bit unsigned integer specified by\r
247 Value and returns the decremented value. The decrement operation must be\r
248 performed using MP safe mechanisms. The state of the return value is not\r
249 guaranteed to be MP safe.\r
250\r
251 If Value is NULL, then ASSERT().\r
252\r
253 @param Value A pointer to the 32-bit value to decrement.\r
254\r
255 @return The decremented value.\r
256\r
257**/\r
258UINT32\r
259EFIAPI\r
260InterlockedDecrement (\r
261 IN UINT32 *Value\r
262 )\r
263{\r
264 ASSERT (Value != NULL);\r
265 return InternalSyncDecrement (Value);\r
266}\r
267\r
268/**\r
269 Performs an atomic compare exchange operation on a 32-bit unsigned integer.\r
270\r
1ea5ca46 271 Performs an atomic compare exchange operation on the 32-bit unsigned integer\r
272 specified by Value. If Value is equal to CompareValue, then Value is set to \r
273 ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue,\r
274 then Value is returned. The compare exchange operation must be performed using \r
275 MP safe mechanisms.\r
276\r
277 If Value is NULL, then ASSERT().\r
278\r
878ddf1f 279 @param Value A pointer to the 32-bit value for the compare exchange\r
280 operation.\r
281 @param CompareValue 32-bit value used in compare operation.\r
282 @param ExchangeValue 32-bit value used in exchange operation.\r
283\r
284 @return The original *Value before exchange.\r
285\r
286**/\r
287UINT32\r
288EFIAPI\r
289InterlockedCompareExchange32 (\r
0ffa1286 290 IN OUT UINT32 *Value,\r
878ddf1f 291 IN UINT32 CompareValue,\r
292 IN UINT32 ExchangeValue\r
293 )\r
294{\r
295 ASSERT (Value != NULL);\r
296 return InternalSyncCompareExchange32 (Value, CompareValue, ExchangeValue);\r
297}\r
298\r
299/**\r
300 Performs an atomic compare exchange operation on a 64-bit unsigned integer.\r
301\r
1ea5ca46 302 Performs an atomic compare exchange operation on the 64-bit unsigned integer specified \r
303 by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and \r
304 CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. \r
305 The compare exchange operation must be performed using MP safe mechanisms.\r
306\r
307 If Value is NULL, then ASSERT().\r
308\r
878ddf1f 309 @param Value A pointer to the 64-bit value for the compare exchange\r
310 operation.\r
311 @param CompareValue 64-bit value used in compare operation.\r
312 @param ExchangeValue 64-bit value used in exchange operation.\r
313\r
314 @return The original *Value before exchange.\r
315\r
316**/\r
317UINT64\r
318EFIAPI\r
319InterlockedCompareExchange64 (\r
0ffa1286 320 IN OUT UINT64 *Value,\r
878ddf1f 321 IN UINT64 CompareValue,\r
322 IN UINT64 ExchangeValue\r
323 )\r
324{\r
325 ASSERT (Value != NULL);\r
326 return InternalSyncCompareExchange64 (Value, CompareValue, ExchangeValue);\r
327}\r
328\r
329/**\r
330 Performs an atomic compare exchange operation on a pointer value.\r
331\r
332 Performs an atomic compare exchange operation on the pointer value specified\r
333 by Value. If Value is equal to CompareValue, then Value is set to\r
334 ExchangeValue and CompareValue is returned. If Value is not equal to\r
335 CompareValue, then Value is returned. The compare exchange operation must be\r
336 performed using MP safe mechanisms.\r
337\r
338 If Value is NULL, then ASSERT().\r
339\r
340 @param Value A pointer to the pointer value for the compare exchange\r
341 operation.\r
342 @param CompareValue Pointer value used in compare operation.\r
343 @param ExchangeValue Pointer value used in exchange operation.\r
344\r
345**/\r
346VOID *\r
347EFIAPI\r
348InterlockedCompareExchangePointer (\r
0ffa1286 349 IN OUT VOID **Value,\r
878ddf1f 350 IN VOID *CompareValue,\r
351 IN VOID *ExchangeValue\r
352 )\r
353{\r
58251024 354 UINT8 SizeOfValue;\r
355\r
356 SizeOfValue = sizeof (*Value);\r
357\r
358 switch (SizeOfValue) {\r
878ddf1f 359 case sizeof (UINT32):\r
360 return (VOID*)(UINTN)InterlockedCompareExchange32 (\r
361 (UINT32*)Value,\r
362 (UINT32)(UINTN)CompareValue,\r
363 (UINT32)(UINTN)ExchangeValue\r
364 );\r
365 case sizeof (UINT64):\r
366 return (VOID*)(UINTN)InterlockedCompareExchange64 (\r
367 (UINT64*)Value,\r
368 (UINT64)(UINTN)CompareValue,\r
369 (UINT64)(UINTN)ExchangeValue\r
370 );\r
371 default:\r
372 ASSERT (FALSE);\r
373 return NULL;\r
374 }\r
375}\r