Thread synchronization--user mode thread synchronization--interlocked implementation

1 thread synchronization is divided into thread synchronization in user mode and thread synchronization of kernel objects. 2 3 Of course, thread synchronization in user mode is faster than kernel mode, but functions are also4 5  6 7 8 //1. Using Atomic access: Interlocked series functions, about interlocked series functions, what I need to know is that they execute extremely fast9 Ten //(1) The first is the InterlockedExchangeAdd brothers function, One //The first parameter, Addend, represents the address of the operand, A //The second parameter, value, represents the added value, and if you want to subtract, pass a negative number -  - LONG InterlockedExchangeAdd ( theLONGvolatile*Addend, - LONG Value); -  - LONG InterlockedExchangeAdd64 ( +LONG64volatile*Addend, - LONG64 Value); + //(2) There are 3 other interlocked functions A  at LONG InterlockedExchange ( -LONGvolatile*Target, - LONG Value); -  - Longlong InterlockedExchange64 ( -LONG64volatile*Target, in LONG64 Value); -  to PVOID InterlockedExchangePointer ( +PVOIDvolatile*Target, - PVOID Value); the  * //InterlockedExchange and InterlockedExchangePointer $ //The current value of the memory address pointed to by the first parameter is replaced atomically with the value specified by the second parameter .Panax Notoginseng  - //(3) The last other interlocked Exchange function the Plong InterlockedCompareExchange ( +LONGvolatile*Destination, A LONG Exchange, the LONG Comperand); +  - Plong Interlockedcompareexchangepointer ( $PVOIDvolatile*Destination, $ PVOID Exchange, - PVOID Comperand); - //pseudo code for function execution the { - if(Destination = =Comperand)Wuyi { theDestination =Exchange; - } Wu } - //The function compares the current value destination with the parameter comparand, if the two values are the same, About //then the function modifies *destination to exchange, otherwise the Destination value is unchanged. $  - //InterlockedExchange and its useful when implementing a rotary lock - //The following shows the rotation lock -BOOL G_fresourceinuse =FALSE; A voidFunc1 () + { the     //waiting to receive resources -      while(InterlockedExchange (&g_fresourceinuse,true) = =TRUE) $Sleep (0); the  the     //Receive Resources the  the     //we do not need to receive resources -InterlockedExchange (&g_fresourceinuse,false); in } the   the  About  the#include"windows.h" the#include"iostream" the using namespacestd; + LongG_x =0 ; -  the //defining thread Functions 1Bayi DWORD WINAPI threadfunone (PVOID pvparam); the  the //Defining thread Functions 2 - DWORD WINAPI threadfuntwo (PVOID pvparam); -  the intMain () the { the     //Create thread 1 theHANDLE Hthreadone = CreateThread (NULL,0, Threadfunone,0,0, NULL); - CloseHandle (hthreadone); the  the     //Create thread 2 theHANDLE hthreadtwo = CreateThread (NULL,0, Threadfuntwo,0,0, NULL);94 CloseHandle (hthreadtwo); the  the     //let the main thread hang first to make sure that the other threads perform the completion theSleep (10000); 98cout<<g_x<<Endl; About     return 0 ; - }101 102 DWORD WINAPI threadfunone (PVOID pvparam)103 {104InterlockedExchangeAdd (&g_x,1) ; the     return 0;106 }107 108 DWORD WINAPI threadfuntwo (PVOID pvparam)109 { theInterlockedExchangeAdd (&g_x,1) ;111     return 0; the }113   the  theLimit, so we should consider thread synchronization in user mode first when using thread synchronization