| /*************************************************************************/ /*! |
| @File lock.h |
| @Title Locking interface |
| @Copyright Copyright (c) Imagination Technologies Ltd. All Rights Reserved |
| @Description Services internal locking interface |
| @License Dual MIT/GPLv2 |
| |
| The contents of this file are subject to the MIT license as set out below. |
| |
| Permission is hereby granted, free of charge, to any person obtaining a copy |
| of this software and associated documentation files (the "Software"), to deal |
| in the Software without restriction, including without limitation the rights |
| to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| copies of the Software, and to permit persons to whom the Software is |
| furnished to do so, subject to the following conditions: |
| |
| The above copyright notice and this permission notice shall be included in |
| all copies or substantial portions of the Software. |
| |
| Alternatively, the contents of this file may be used under the terms of |
| the GNU General Public License Version 2 ("GPL") in which case the provisions |
| of GPL are applicable instead of those above. |
| |
| If you wish to allow use of your version of this file only under the terms of |
| GPL, and not to allow others to use your version of this file under the terms |
| of the MIT license, indicate your decision by deleting the provisions above |
| and replace them with the notice and other provisions required by GPL as set |
| out in the file called "GPL-COPYING" included in this distribution. If you do |
| not delete the provisions above, a recipient may use your version of this file |
| under the terms of either the MIT license or GPL. |
| |
| This License is also included in this distribution in the file called |
| "MIT-COPYING". |
| |
| EXCEPT AS OTHERWISE STATED IN A NEGOTIATED AGREEMENT: (A) THE SOFTWARE IS |
| PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING |
| BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR |
| PURPOSE AND NONINFRINGEMENT; AND (B) IN NO EVENT SHALL THE AUTHORS OR |
| COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER |
| IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN |
| CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| */ /**************************************************************************/ |
| |
| #ifndef _LOCK_H_ |
| #define _LOCK_H_ |
| |
| /* In Linux kernel mode we are using the kernel mutex implementation directly |
| * with macros. This allows us to use the kernel lockdep feature for lock |
| * debugging. */ |
| #include "lock_types.h" |
| |
| #if defined(LINUX) && defined(__KERNEL__) |
| |
| #include "allocmem.h" |
| #include <asm/atomic.h> |
| |
| #define OSLockCreateNoStats(phLock, eLockType) ({ \ |
| PVRSRV_ERROR e = PVRSRV_ERROR_OUT_OF_MEMORY; \ |
| *(phLock) = OSAllocMemNoStats(sizeof(struct mutex)); \ |
| if (*(phLock)) { mutex_init(*(phLock)); e = PVRSRV_OK; }; \ |
| e;}) |
| #define OSLockCreate(phLock, eLockType) ({ \ |
| PVRSRV_ERROR e = PVRSRV_ERROR_OUT_OF_MEMORY; \ |
| *(phLock) = OSAllocMem(sizeof(struct mutex)); \ |
| if (*(phLock)) { mutex_init(*(phLock)); e = PVRSRV_OK; }; \ |
| e;}) |
| #define OSLockDestroy(hLock) ({mutex_destroy((hLock)); OSFreeMem((hLock)); PVRSRV_OK;}) |
| #define OSLockDestroyNoStats(hLock) ({mutex_destroy((hLock)); OSFreeMemNoStats((hLock)); PVRSRV_OK;}) |
| |
| #define OSLockAcquire(hLock) ({mutex_lock((hLock)); PVRSRV_OK;}) |
| #define OSLockAcquireNested(hLock, subclass) ({mutex_lock_nested((hLock), (subclass)); PVRSRV_OK;}) |
| #define OSLockRelease(hLock) ({mutex_unlock((hLock)); PVRSRV_OK;}) |
| |
| #define OSLockIsLocked(hLock) ((mutex_is_locked((hLock)) == 1) ? IMG_TRUE : IMG_FALSE) |
| #define OSTryLockAcquire(hLock) ((mutex_trylock(hLock) == 1) ? IMG_TRUE : IMG_FALSE) |
| |
| /* These _may_ be reordered or optimized away entirely by the compiler/hw */ |
| #define OSAtomicRead(pCounter) atomic_read(pCounter) |
| #define OSAtomicWrite(pCounter, i) atomic_set(pCounter, i) |
| |
| /* The following atomic operations, in addition to being SMP-safe, also |
| imply a memory barrier around the operation */ |
| #define OSAtomicIncrement(pCounter) atomic_inc_return(pCounter) |
| #define OSAtomicDecrement(pCounter) atomic_dec_return(pCounter) |
| #define OSAtomicCompareExchange(pCounter, oldv, newv) atomic_cmpxchg(pCounter,oldv,newv) |
| |
| #define OSAtomicAdd(pCounter, incr) atomic_add_return(incr,pCounter) |
| #define OSAtomicAddUnless(pCounter, incr, test) __atomic_add_unless(pCounter,incr,test) |
| |
| #define OSAtomicSubtract(pCounter, incr) atomic_add_return(-(incr),pCounter) |
| #define OSAtomicSubtractUnless(pCounter, incr, test) OSAtomicAddUnless(pCounter, -(incr), test) |
| |
| #else /* defined(LINUX) && defined(__KERNEL__) */ |
| |
| #include "img_types.h" |
| #include "pvrsrv_error.h" |
| |
| /**************************************************************************/ /*! |
| @Function OSLockCreate |
| @Description Creates an operating system lock object. |
| @Output phLock The created lock. |
| @Input eLockType The type of lock required. This may be: |
| LOCK_TYPE_PASSIVE - the lock will not be used |
| in interrupt context or |
| LOCK_TYPE_DISPATCH - the lock may be used |
| in interrupt context. |
| @Return PVRSRV_OK on success. PVRSRV_ERROR_OUT_OF_MEMORY if the driver |
| cannot allocate CPU memory needed for the lock. |
| PVRSRV_ERROR_INIT_FAILURE if the Operating System fails to |
| allocate the lock. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| PVRSRV_ERROR OSLockCreate(POS_LOCK *phLock, LOCK_TYPE eLockType); |
| #if defined(INTEGRITY_OS) |
| #define OSLockCreateNoStats OSLockCreate |
| #endif |
| |
| /**************************************************************************/ /*! |
| @Function OSLockDestroy |
| @Description Destroys an operating system lock object. |
| @Input hLock The lock to be destroyed. |
| @Return None. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| PVRSRV_ERROR OSLockDestroy(POS_LOCK hLock); |
| |
| #if defined(INTEGRITY_OS) |
| #define OSLockDestroyNoStats OSLockDestroy |
| #endif |
| /**************************************************************************/ /*! |
| @Function OSLockAcquire |
| @Description Acquires an operating system lock. |
| NB. This function must not return until the lock is acquired |
| (meaning the implementation should not timeout or return with |
| an error, as the caller will assume they have the lock). |
| @Input hLock The lock to be acquired. |
| @Return None. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| void OSLockAcquire(POS_LOCK hLock); |
| |
| /* Nested notation isn't used in UM or other OS's */ |
| /**************************************************************************/ /*! |
| @Function OSLockAcquireNested |
| @Description For operating systems other than Linux, this equates to an |
| OSLockAcquire() call. On Linux, this function wraps a call |
| to mutex_lock_nested(). This recognises the scenario where |
| there may be multiple subclasses within a particular class |
| of lock. In such cases, the order in which the locks belonging |
| these various subclasses are acquired is important and must be |
| validated. |
| @Input hLock The lock to be acquired. |
| @Input subclass The subclass of the lock. |
| @Return None. |
| */ /**************************************************************************/ |
| #define OSLockAcquireNested(hLock, subclass) OSLockAcquire((hLock)) |
| |
| /**************************************************************************/ /*! |
| @Function OSLockRelease |
| @Description Releases an operating system lock. |
| @Input hLock The lock to be released. |
| @Return None. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| void OSLockRelease(POS_LOCK hLock); |
| |
| /**************************************************************************/ /*! |
| @Function OSLockIsLocked |
| @Description Tests whether or not an operating system lock is currently |
| locked. |
| @Input hLock The lock to be tested. |
| @Return IMG_TRUE if locked, IMG_FALSE if not locked. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_BOOL OSLockIsLocked(POS_LOCK hLock); |
| |
| #if defined(LINUX) |
| |
| /* Use GCC intrinsics (read/write semantics consistent with kernel-side implementation) */ |
| #define OSAtomicRead(pCounter) (*(volatile int *)&(pCounter)->counter) |
| #define OSAtomicWrite(pCounter, i) ((pCounter)->counter = (IMG_INT) i) |
| #define OSAtomicIncrement(pCounter) __sync_add_and_fetch((&(pCounter)->counter), 1) |
| #define OSAtomicDecrement(pCounter) __sync_sub_and_fetch((&(pCounter)->counter), 1) |
| #define OSAtomicCompareExchange(pCounter, oldv, newv) \ |
| __sync_val_compare_and_swap((&(pCounter)->counter), oldv, newv) |
| |
| #define OSAtomicAdd(pCounter, incr) __sync_add_and_fetch((&(pCounter)->counter), incr) |
| #define OSAtomicAddUnless(pCounter, incr, test) ({ \ |
| int c; int old; \ |
| c = OSAtomicRead(pCounter); \ |
| while (1) { \ |
| if (c == (test)) break; \ |
| old = OSAtomicCompareExchange(pCounter, c, c+(incr)); \ |
| if (old == c) break; \ |
| c = old; \ |
| } c; }) |
| |
| #define OSAtomicSubtract(pCounter, incr) OSAtomicAdd(pCounter, -(incr)) |
| #define OSAtomicSubtractUnless(pCounter, incr, test) OSAtomicAddUnless(pCounter, -(incr), test) |
| |
| #else |
| |
| /* These _may_ be reordered or optimized away entirely by the compiler/hw */ |
| /*************************************************************************/ /*! |
| @Function OSAtomicRead |
| @Description Read the value of a variable atomically. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to read |
| @Return The value of the atomic variable |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicRead(ATOMIC_T *pCounter); |
| |
| /*************************************************************************/ /*! |
| @Function OSAtomicWrite |
| @Description Write the value of a variable atomically. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to be written to |
| @Input v The value to write |
| @Return None |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| void OSAtomicWrite(ATOMIC_T *pCounter, IMG_INT v); |
| |
| /* For the following atomic operations, in addition to being SMP-safe, |
| should also have a memory barrier around each operation */ |
| /*************************************************************************/ /*! |
| @Function OSAtomicIncrement |
| @Description Increment the value of a variable atomically. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to be incremented |
| @Return The new value of *pCounter. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicIncrement(ATOMIC_T *pCounter); |
| |
| /*************************************************************************/ /*! |
| @Function OSAtomicDecrement |
| @Description Decrement the value of a variable atomically. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to be decremented |
| @Return The new value of *pCounter. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicDecrement(ATOMIC_T *pCounter); |
| |
| /*************************************************************************/ /*! |
| @Function OSAtomicAdd |
| @Description Add a specified value to a variable atomically. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to add the value to |
| @Input v The value to be added |
| @Return The new value of *pCounter. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicAdd(ATOMIC_T *pCounter, IMG_INT v); |
| |
| /*************************************************************************/ /*! |
| @Function OSAtomicAddUnless |
| @Description Add a specified value to a variable atomically unless it |
| already equals a particular value. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to add the value to |
| @Input v The value to be added to 'pCounter' |
| @Input t The test value. If 'pCounter' equals this, |
| its value will not be adjusted |
| @Return The new value of *pCounter. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicAddUnless(ATOMIC_T *pCounter, IMG_INT v, IMG_INT t); |
| |
| /*************************************************************************/ /*! |
| @Function OSAtomicSubtract |
| @Description Subtract a specified value to a variable atomically. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to subtract the value from |
| @Input v The value to be subtracted |
| @Return The new value of *pCounter. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicSubtract(ATOMIC_T *pCounter, IMG_INT v); |
| |
| /*************************************************************************/ /*! |
| @Function OSAtomicSubtractUnless |
| @Description Subtract a specified value from a variable atomically unless |
| it already equals a particular value. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to subtract the value from |
| @Input v The value to be subtracted from 'pCounter' |
| @Input t The test value. If 'pCounter' equals this, |
| its value will not be adjusted |
| @Return The new value of *pCounter. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicSubtractUnless(ATOMIC_T *pCounter, IMG_INT v, IMG_INT t); |
| |
| /*************************************************************************/ /*! |
| @Function OSAtomicCompareExchange |
| @Description Set a variable to a given value only if it is currently |
| equal to a specified value. The whole operation must be atomic. |
| Atomic functions must be implemented in a manner that |
| is both symmetric multiprocessor (SMP) safe and has a memory |
| barrier around each operation. |
| @Input pCounter The atomic variable to be checked and |
| possibly updated |
| @Input oldv The value the atomic variable must have in |
| order to be modified |
| @Input newv The value to write to the atomic variable if |
| it equals 'oldv' |
| @Return The value of *pCounter after the function. |
| */ /**************************************************************************/ |
| IMG_INTERNAL |
| IMG_INT OSAtomicCompareExchange(ATOMIC_T *pCounter, IMG_INT oldv, IMG_INT newv); |
| |
| #endif /* defined(LINUX) */ |
| #endif /* defined(LINUX) && defined(__KERNEL__) */ |
| |
| #endif /* _LOCK_H_ */ |
