KernelLand/Kernel/workqueue.c

   1 /*
   2  * Acess2 Kernel
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * workqueue.c
   6  * - Worker FIFO Queue (Single Consumer, Interrupt Producer)
   7  */
   8 #include <acess.h>
   9 #include <workqueue.h>
  10 #include <threads_int.h>
  11
  12 #define QUEUENEXT(ptr)  (*( (void**)(ptr) + Queue->NextOffset/sizeof(void*) ))
  13
  14 // === CODE ===
  15 void Workqueue_Init(tWorkqueue *Queue, const char *Name, size_t NextOfset)
  16 {
  17         Queue->Name = Name;
  18         Queue->NextOffset = NextOfset;
  19 }
  20
  21 void *Workqueue_GetWork(tWorkqueue *Queue)
  22 {
  23         for( ;; )
  24         {
  25                 // Check for work
  26                 SHORTLOCK(&Queue->Protector);
  27                 if(Queue->Head)
  28                 {
  29                         void *ret = Queue->Head;
  30                         Queue->Head = QUEUENEXT( ret );
  31                         if(Queue->Tail == ret)
  32                                 Queue->Tail = NULL;
  33                         SHORTREL(&Queue->Protector);
  34                         return ret;
  35                 }
  36
  37                 Threads_int_Sleep(THREAD_STAT_QUEUESLEEP,
  38                         Queue, 0,
  39                         &Queue->Sleeper, NULL, &Queue->Protector);
  40         }
  41 }
  42
  43 void Workqueue_AddWork(tWorkqueue *Queue, void *Ptr)
  44 {
  45         SHORTLOCK(&Queue->Protector);
  46
  47         if( Queue->Tail )
  48                 QUEUENEXT(Queue->Tail) = Ptr;
  49         else
  50                 Queue->Head = Ptr;
  51         Queue->Tail = Ptr;
  52         QUEUENEXT(Ptr) = NULL;
  53
  54         if( Queue->Sleeper )
  55         {
  56                 if( Queue->Sleeper->Status != THREAD_STAT_ACTIVE )
  57                         Threads_AddActive(Queue->Sleeper);
  58                 Queue->Sleeper = NULL;
  59         }
  60         SHORTREL(&Queue->Protector);
  61 }