/* Up the semaphore's count and release any thread waiting at the head of the
* queue. The count is saturated to the value of the 'max' parameter specified
* in 'semaphore_init'. */
void semaphore_release(struct semaphore *s)
{
unsigned int result = THREAD_NONE;
int oldlevel = disable_irq_save();
corelock_lock(&s->cl);
struct thread_entry *thread = WQ_THREAD_FIRST(&s->queue);
if(LIKELY(thread != NULL))
{
/* a thread was queued - wake it up and keep count at 0 */
KERNEL_ASSERT(s->count == 0,
"semaphore_release->threads queued but count=%d!\n", s->count);
result = wakeup_thread(thread, WAKEUP_DEFAULT);
}
else
{
int count = s->count;
if(count < s->max)
{
/* nothing waiting - up it */
s->count = count + 1;
}
}
corelock_unlock(&s->cl);
restore_irq(oldlevel);
#if defined(HAVE_PRIORITY_SCHEDULING) && defined(is_thread_context)
/* No thread switch if not thread context */
if((result & THREAD_SWITCH) && is_thread_context())
switch_thread();
#endif
(void)result;
}
static int kbd_irq( int nIrqNum, void* pData, SysCallRegs_s* psRegs )
{
int nCode;
int nEFlg;
int n;
nCode = inb_p( 0x60 );
nEFlg = cli();
n = inb_p( 0x61 );
outb_p( n | 0x80, 0x61 );
outb_p( n & ~0x80, 0x61 );
nCode = ConvertKeyCode( nCode );
if ( 0 != nCode )
{
g_sVolume.zBuffer[ atomic_inc_and_read( &g_sVolume.nInPos ) & 0xff ] = nCode;
atomic_inc( &g_sVolume.nBytesReceived );
if ( -1 != g_sVolume.hWaitThread ) {
wakeup_thread( g_sVolume.hWaitThread, false );
}
}
put_cpu_flags( nEFlg );
return( 0 );
}
/* Puts the specified return value in the waiting thread's return value
* and wakes the thread.
*
* A sender should be confirmed to exist before calling which makes it
* more efficent to reject the majority of cases that don't need this
* called.
*/
static void queue_release_sender(struct thread_entry * volatile * sender,
intptr_t retval)
{
struct thread_entry *thread = *sender;
*sender = NULL; /* Clear slot. */
#ifdef HAVE_WAKEUP_EXT_CB
thread->wakeup_ext_cb = NULL; /* Clear callback. */
#endif
thread->retval = retval; /* Assign thread-local return value. */
*thread->bqp = thread; /* Move blocking queue head to thread since
wakeup_thread wakes the first thread in
the list. */
wakeup_thread(thread->bqp);
}
static int kbd_write( void* pNode, void* pCookie, off_t nPosition, const void* pBuffer, size_t nSize )
{
int i;
for ( i = 0 ; i < nSize ; ++i )
{
g_sVolume.zBuffer[ atomic_inc_and_read( &g_sVolume.nInPos ) & 0xff ] = ((char *)pBuffer)[i];
atomic_inc( &g_sVolume.nBytesReceived );
if ( -1 != g_sVolume.hWaitThread )
{
wakeup_thread( g_sVolume.hWaitThread, false );
}
}
return(nSize);
}
unsigned int thread_queue_wake(struct thread_entry **list)
{
unsigned int result = THREAD_NONE;
for (;;)
{
unsigned int rc = wakeup_thread(list);
if (rc == THREAD_NONE)
break;
result |= rc;
}
return result;
}
/* Release ownership of a mutex object - only owning thread must call this */
void mutex_unlock(struct mutex *m)
{
/* unlocker not being the owner is an unlocking violation */
KERNEL_ASSERT(m->blocker.thread == __running_self_entry(),
"mutex_unlock->wrong thread (%s != %s)\n",
m->blocker.thread->name,
__running_self_entry()->name);
if(m->recursion > 0)
{
/* this thread still owns lock */
m->recursion--;
return;
}
/* lock out other cores */
corelock_lock(&m->cl);
/* transfer to next queued thread if any */
struct thread_entry *thread = WQ_THREAD_FIRST(&m->queue);
if(LIKELY(thread == NULL))
{
/* no threads waiting - open the lock */
m->blocker.thread = NULL;
corelock_unlock(&m->cl);
return;
}
const int oldlevel = disable_irq_save();
/* Tranfer of owning thread is handled in the wakeup protocol
* if priorities are enabled otherwise just set it from the
* queue head. */
#ifndef HAVE_PRIORITY_SCHEDULING
m->blocker.thread = thread;
#endif
unsigned int result = wakeup_thread(thread, WAKEUP_TRANSFER);
restore_irq(oldlevel);
corelock_unlock(&m->cl);
#ifdef HAVE_PRIORITY_SCHEDULING
if(result & THREAD_SWITCH)
switch_thread();
#endif
(void)result;
}
acpi_status
acpi_os_execute(
u32 priority,
acpi_osd_exec_callback function,
void *context)
{
acpi_status status = AE_OK;
struct acpi_os_dpc *dpc;
thread_id id;
ACPI_FUNCTION_TRACE ("os_queue_for_execution");
ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Scheduling function [%p(%p)] for deferred execution.\n", function, context));
if (!function)
return_ACPI_STATUS (AE_BAD_PARAMETER);
/*
* Allocate/initialize DPC structure. Note that this memory will be
* freed by the callee. The kernel handles the tq_struct list in a
* way that allows us to also free its memory inside the callee.
* Because we may want to schedule several tasks with different
* parameters we can't use the approach some kernel code uses of
* having a static tq_struct.
* We can save time and code by allocating the DPC and tq_structs
* from the same memory.
*/
dpc = kmalloc(sizeof(struct acpi_os_dpc), MEMF_KERNEL | MEMF_CLEAR );
if (!dpc)
return_ACPI_STATUS (AE_NO_MEMORY);
dpc->function = function;
dpc->context = context;
id = spawn_kernel_thread( "acpi_task", acpi_os_execute_deferred,
0, 4096, dpc );
wakeup_thread( id, false );
return_ACPI_STATUS ( status );
}
