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Diffstat (limited to 'c/src/exec/score/src/threadstartmultitasking.c')
-rw-r--r-- | c/src/exec/score/src/threadstartmultitasking.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/c/src/exec/score/src/threadstartmultitasking.c b/c/src/exec/score/src/threadstartmultitasking.c new file mode 100644 index 0000000000..8c9baa70af --- /dev/null +++ b/c/src/exec/score/src/threadstartmultitasking.c @@ -0,0 +1,90 @@ +/* + * Thread Handler + * + * + * COPYRIGHT (c) 1989-1998. + * On-Line Applications Research Corporation (OAR). + * Copyright assigned to U.S. Government, 1994. + * + * The license and distribution terms for this file may be + * found in found in the file LICENSE in this distribution or at + * http://www.OARcorp.com/rtems/license.html. + * + * $Id$ + */ + +#include <rtems/system.h> +#include <rtems/score/apiext.h> +#include <rtems/score/context.h> +#include <rtems/score/interr.h> +#include <rtems/score/isr.h> +#include <rtems/score/object.h> +#include <rtems/score/priority.h> +#include <rtems/score/states.h> +#include <rtems/score/sysstate.h> +#include <rtems/score/thread.h> +#include <rtems/score/threadq.h> +#include <rtems/score/userext.h> +#include <rtems/score/wkspace.h> + +/*PAGE + * + * _Thread_Start_multitasking + * + * This kernel routine readies the requested thread, the thread chain + * is adjusted. A new heir thread may be selected. + * + * Input parameters: + * system_thread - pointer to system initialization thread control block + * idle_thread - pointer to idle thread control block + * + * Output parameters: NONE + * + * NOTE: This routine uses the "blocking" heir selection mechanism. + * This insures the correct heir after a thread restart. + * + * INTERRUPT LATENCY: + * ready chain + * select heir + */ + +void _Thread_Start_multitasking( void ) +{ + /* + * The system is now multitasking and completely initialized. + * This system thread now either "goes away" in a single processor + * system or "turns into" the server thread in an MP system. + */ + + _System_state_Set( SYSTEM_STATE_UP ); + + _Context_Switch_necessary = FALSE; + + _Thread_Executing = _Thread_Heir; + + /* + * Get the init task(s) running. + * + * Note: Thread_Dispatch() is normally used to dispatch threads. As + * part of its work, Thread_Dispatch() restores floating point + * state for the heir task. + * + * This code avoids Thread_Dispatch(), and so we have to restore + * (actually initialize) the floating point state "by hand". + * + * Ignore the CPU_USE_DEFERRED_FP_SWITCH because we must always + * switch in the first thread if it is FP. + */ + + +#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE ) + /* + * don't need to worry about saving BSP's floating point state + */ + + if ( _Thread_Heir->fp_context != NULL ) + _Context_Restore_fp( &_Thread_Heir->fp_context ); +#endif + + _Context_Switch( &_Thread_BSP_context, &_Thread_Heir->Registers ); +} |