ecos: packages/kernel/current/src/sched/sched.cxx annotate

annotate packages/kernel/current/src/sched/sched.cxx @ 115:6ed91473a1cd ecos-sw-2000-08-21

Merge from eCos master repository on 2000-08-21-22:40:54-BST

author	jlarmour
date	Fri, 25 Aug 2000 17:32:38 +0000
parents	59d97b6ba612
children	0ec04793409a

rev	line source
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	1 //==========================================================================
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	2 //
2 443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	3 // sched/sched.cxx
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	4 //
2 443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	5 // Scheduler class implementations
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	6 //
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	7 //==========================================================================
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	8 //####COPYRIGHTBEGIN####
64 c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	9 //
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	10 // -------------------------------------------
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	11 // The contents of this file are subject to the Red Hat eCos Public License
66 bf00f99aec69 Merge from eCos master repository on 2000-02-02-19:16:44-GMT jlarmour parents: 64 diff changeset	12 // Version 1.1 (the "License"); you may not use this file except in
64 c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	13 // compliance with the License. You may obtain a copy of the License at
66 bf00f99aec69 Merge from eCos master repository on 2000-02-02-19:16:44-GMT jlarmour parents: 64 diff changeset	14 // http://www.redhat.com/
64 c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	15 //
66 bf00f99aec69 Merge from eCos master repository on 2000-02-02-19:16:44-GMT jlarmour parents: 64 diff changeset	16 // Software distributed under the License is distributed on an "AS IS"
64 c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	17 // basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	18 // License for the specific language governing rights and limitations under
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	19 // the License.
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	20 //
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	21 // The Original Code is eCos - Embedded Configurable Operating System,
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	22 // released September 30, 1998.
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	23 //
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	24 // The Initial Developer of the Original Code is Red Hat.
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	25 // Portions created by Red Hat are
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	26 // Copyright (C) 1998, 1999, 2000 Red Hat, Inc.
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	27 // All Rights Reserved.
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	28 // -------------------------------------------
c38311975d4f Merge from eCos master repository on 2000-01-28-04:28:11-GMT jlarmour parents: 62 diff changeset	29 //
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	30 //####COPYRIGHTEND####
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	31 //==========================================================================
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	32 //#####DESCRIPTIONBEGIN####
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	33 //
2 443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	34 // Author(s): nickg
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	35 // Contributors: nickg
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	36 // Date: 1997-09-15
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	37 // Purpose: Scheduler class implementation
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	38 // Description: This file contains the definitions of the scheduler class
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	39 // member functions that are common to all scheduler
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	40 // implementations.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	41 //
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	42 //####DESCRIPTIONEND####
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	43 //
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	44 //==========================================================================
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	45
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	46 #include <pkgconf/kernel.h>
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	47
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	48 #include <cyg/kernel/ktypes.h> // base kernel types
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	49 #include <cyg/infra/cyg_trac.h> // tracing macros
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	50 #include <cyg/infra/cyg_ass.h> // assertion macros
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	51 #include <cyg/kernel/instrmnt.h> // instrumentation
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	52
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	53 #include <cyg/kernel/sched.hxx> // our header
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	54
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	55 #include <cyg/kernel/thread.hxx> // thread classes
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	56 #include <cyg/kernel/intr.hxx> // Interrupt interface
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	57
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	58 #include <cyg/hal/hal_arch.h> // Architecture specific definitions
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	59
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	60 #include <cyg/kernel/thread.inl> // thread inlines
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	61 #include <cyg/kernel/sched.inl> // scheduler inlines
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	62
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	63 //-------------------------------------------------------------------------
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	64 // Some local tracing control - a default.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	65 #ifdef CYGDBG_USE_TRACING
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	66 # if !defined( CYGDBG_INFRA_DEBUG_TRACE_ASSERT_SIMPLE ) && \
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	67 !defined( CYGDBG_INFRA_DEBUG_TRACE_ASSERT_FANCY )
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	68 // ie. not a tracing implementation that takes a long time to output
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	69
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	70 # ifndef CYGDBG_KERNEL_TRACE_UNLOCK_INNER
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	71 # define CYGDBG_KERNEL_TRACE_UNLOCK_INNER
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	72 # endif // control not already defined
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	73
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	74 # endif // trace implementation not ..._SIMPLE && not ..._FANCY
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	75 #endif // CYGDBG_USE_TRACING
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	76
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	77 // -------------------------------------------------------------------------
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	78 // Static Cyg_Scheduler class members
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	79
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	80 // We start with sched_lock at 1 so that any kernel code we
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	81 // call during initialization will not try to reschedule.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	82
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	83 volatile cyg_ucount32 Cyg_Scheduler_Base::sched_lock = 1;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	84
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	85 Cyg_Thread *Cyg_Scheduler_Base::current_thread = NULL;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	86
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	87 cyg_bool Cyg_Scheduler_Base::need_reschedule = false;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	88
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	89 Cyg_Scheduler Cyg_Scheduler::scheduler CYG_INIT_PRIORITY( SCHEDULER );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	90
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	91 cyg_ucount32 Cyg_Scheduler_Base::thread_switches = 0;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	92
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	93 // -------------------------------------------------------------------------
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	94 // Scheduler unlock function.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	95
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	96 // This is only called when the lock is to be zeroed and there is the
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	97 // potential for real work to be done. Other cases are handled in
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	98 // Cyg_Scheduler::unlock() which is an inline. The new_lock argument
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	99 // contains the value that the scheduler lock should have after this
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	100 // function has completed. If it is zero then the lock is being
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	101 // released and some extra work (running ASRs, checking for DSRs) is
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	102 // done before returning. If it is non-zero then it must equal the
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	103 // current value of the lock, and is used to indicate that we want to
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	104 // reacquire the scheduler lock before returning. This latter option
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	105 // only makes any sense if the current thread is no longer runnable,
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	106 // otherwise this function will do nothing.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	107
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	108 void Cyg_Scheduler::unlock_inner( cyg_ucount32 new_lock )
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	109 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	110 #ifdef CYGDBG_KERNEL_TRACE_UNLOCK_INNER
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	111 CYG_REPORT_FUNCTION();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	112 #endif
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	113
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	114 // This assert must be outside the loop because running DSRs can make
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	115 // it fail if the current thread that was about to sleep is awoken by
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	116 // the DSR! Going round the loop to run new DSRs does the same.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	117 CYG_ASSERT( (new_lock == 0) \|\|
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	118 (current_thread->state != Cyg_Thread::RUNNING \|\|
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	119 need_reschedule) ,
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	120 "Unnecessary call to unlock_inner()" );
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	121
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	122 do {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	123
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	124 CYG_PRECONDITION( new_lock==0 ? sched_lock == 1 : sched_lock == new_lock,
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	125 "sched_lock not at expected value" );
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	126
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	127 #ifdef CYGIMP_KERNEL_INTERRUPTS_DSRS
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	128
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	129 // Call any pending DSRs. Do this here to ensure that any
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	130 // threads that get awakened are properly scheduled.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	131
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	132 if( Cyg_Interrupt::DSRs_pending() )
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	133 Cyg_Interrupt::call_pending_DSRs();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	134 #endif
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	135
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	136 Cyg_Thread *current = current_thread;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	137
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	138 CYG_ASSERTCLASS( current, "Bad current thread" );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	139
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	140 // If the current thread is going to sleep, or someone
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	141 // wants a reschedule, choose another thread to run
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	142
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	143 if( current->state != Cyg_Thread::RUNNING \|\| need_reschedule ) {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	144
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	145 CYG_INSTRUMENT_SCHED(RESCHEDULE,0,0);
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	146
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	147 // Get the next thread to run from scheduler
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	148 Cyg_Thread *next = scheduler.schedule();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	149
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	150 CYG_CHECK_DATA_PTR( next, "Invalid next thread pointer");
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	151 CYG_ASSERTCLASS( next, "Bad next thread" );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	152
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	153 if( current != next )
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	154 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	155
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	156 CYG_INSTRUMENT_THREAD(SWITCH,current,next);
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	157
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	158 // Count this thread switch
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	159 thread_switches++;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	160
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	161 // Switch contexts
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	162 HAL_THREAD_SWITCH_CONTEXT( &current->stack_ptr,
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	163 &next->stack_ptr );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	164
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	165 // Worry here about possible compiler
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	166 // optimizations across the above call that may try to
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	167 // propogate common subexpresions. We would end up
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	168 // with the expression from one thread in its
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	169 // successor. This is only a worry if we do not save
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	170 // and restore the complete register set. We need a
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	171 // way of marking functions that return into a
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	172 // different context. A temporary fix would be to
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	173 // disable CSE (-fdisable-cse) in the compiler.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	174
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	175 // We return here only when the current thread is
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	176 // rescheduled. There is a bit of housekeeping to do
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	177 // here before we are allowed to go on our way.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	178
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	179 CYG_CHECK_DATA_PTR( current, "Invalid current thread pointer");
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	180 CYG_ASSERTCLASS( current, "Bad current thread" );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	181
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	182 current_thread = current; // restore current thread pointer
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	183
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	184 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	185
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	186 #ifdef CYGSEM_KERNEL_SCHED_TIMESLICE
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	187 // Reset the timeslice counter so that this thread gets a full
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	188 // quantum.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	189 reset_timeslice_count();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	190 #endif
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	191
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	192 need_reschedule = false; // finished rescheduling
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	193 }
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	194
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	195 if( new_lock == 0 )
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	196 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	197
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	198 #ifdef CYGSEM_KERNEL_SCHED_ASR_SUPPORT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	199
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	200 // Check whether the ASR is pending and not inhibited. If
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	201 // we can call it, then transfer this info to a local
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	202 // variable (call_asr) and clear the pending flag. Note
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	203 // that we only do this if the scheduler lock is about to
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	204 // be zeroed. In any other circumstance we are not
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	205 // unlocking.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	206
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	207 cyg_bool call_asr = false;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	208
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	209 if( !current->asr_inhibit && current->asr_pending )
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	210 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	211 call_asr = true;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	212 current->asr_pending = false;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	213 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	214 #endif
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	215
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	216 HAL_REORDER_BARRIER(); // Make sure everything above has happened
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	217 // by this point
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	218 sched_lock = 0; // Clear the lock
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	219 HAL_REORDER_BARRIER();
2 443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	220
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	221 #ifdef CYGIMP_KERNEL_INTERRUPTS_DSRS
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	222
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	223 // Now check whether any DSRs got posted during the thread
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	224 // switch and if so, go around again. Making this test after
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	225 // the lock has been zeroed avoids a race condition in which
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	226 // a DSR could have been posted during a reschedule, but would
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	227 // not be run until the _next_ time we release the sched lock.
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	228
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	229 if( Cyg_Interrupt::DSRs_pending() ) {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	230 sched_lock = 1; // reclaim the lock
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	231 continue; // go back to head of loop
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	232 }
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	233
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	234 #endif
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	235 // Otherwise the lock is zero, we can return.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	236
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	237 CYG_POSTCONDITION( sched_lock == 0, "sched_lock not zero" );
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	238
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	239 #ifdef CYGSEM_KERNEL_SCHED_ASR_SUPPORT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	240 // If the test within the sched_lock indicating that the ASR
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	241 // be called was true, call it here. Calling the ASR must be
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	242 // the very last thing we do here, since it must run as close
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	243 // to "user" state as possible.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	244
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	245 if( call_asr ) current->asr(current->asr_data);
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	246 #endif
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	247
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	248 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	249 else
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	250 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	251 // If new_lock is non-zero then we restore the sched_lock to
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	252 // the value given.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	253
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	254 HAL_REORDER_BARRIER();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	255
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	256 sched_lock = new_lock;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	257
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	258 HAL_REORDER_BARRIER();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	259 }
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	260
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	261 #ifdef CYGDBG_KERNEL_TRACE_UNLOCK_INNER
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	262 CYG_REPORT_RETURN();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	263 #endif
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	264 return;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	265
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	266 } while( 1 );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	267
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	268 CYG_FAIL( "Should not be executed" );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	269 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	270
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	271 // -------------------------------------------------------------------------
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	272 // Start the scheduler. This is called after the initial threads have been
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	273 // created to start scheduling.
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	274
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	275 void Cyg_Scheduler::start()
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	276 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	277 CYG_REPORT_FUNCTION();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	278
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	279 // Get the first thread to run from scheduler
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	280 register Cyg_Thread *next = scheduler.schedule();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	281
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	282 CYG_ASSERTCLASS( next, "Bad initial thread" );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	283
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	284 need_reschedule = false; // finished rescheduling
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	285 current_thread = next; // restore current thread pointer
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	286
2 443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	287 #ifdef CYGVAR_KERNEL_COUNTERS_CLOCK
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	288 // Reference the real time clock. This ensures that at least one
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	289 // reference to the kernel_clock.o object exists, without which
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	290 // the object will not be included while linking.
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	291 CYG_REFERENCE_OBJECT( Cyg_Clock::real_time_clock );
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	292 #endif
443894e2e912 Block commit of eCos version 1.2.1 jlarmour parents: 0 diff changeset	293
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	294 // Let the interrupts go
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	295 Cyg_Interrupt::enable_interrupts();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	296
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	297 HAL_THREAD_LOAD_CONTEXT( &next->stack_ptr );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	298
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	299 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	300
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	301 // -------------------------------------------------------------------------
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	302 // Consistency checker
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	303
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	304 #ifdef CYGDBG_USE_ASSERTS
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	305
78 59d97b6ba612 Merge from eCos master repository on 2000-03-28-19:50:47-BST jlarmour parents: 66 diff changeset	306 cyg_bool Cyg_Scheduler::check_this( cyg_assert_class_zeal zeal) const
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	307 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	308 CYG_REPORT_FUNCTION();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	309
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	310 // check that we have a non-NULL pointer first
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	311 if( this == NULL ) return false;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	312
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	313 switch( zeal )
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	314 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	315 case cyg_system_test:
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	316 case cyg_extreme:
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	317 case cyg_thorough:
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	318 if( !current_thread->check_this(zeal) ) return false;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	319 case cyg_quick:
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	320 case cyg_trivial:
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	321 case cyg_none:
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	322 default:
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	323 break;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	324 };
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	325
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	326 return true;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	327 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	328
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	329 #endif
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	330
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	331 //==========================================================================
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	332 // SchedThread members
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	333
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	334 // -------------------------------------------------------------------------
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	335 // Static data members
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	336
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	337 #ifdef CYGSEM_KERNEL_SCHED_ASR_SUPPORT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	338
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	339 # ifdef CYGSEM_KERNEL_SCHED_ASR_GLOBAL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	340 Cyg_ASR *Cyg_SchedThread::asr = &Cyg_SchedThread::asr_default;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	341 # endif
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	342
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	343 # ifdef CYGSEM_KERNEL_SCHED_ASR_DATA_GLOBAL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	344 CYG_ADDRWORD Cyg_SchedThread::asr_data = 0;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	345 # endif
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	346
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	347 #endif // CYGSEM_KERNEL_SCHED_ASR_SUPPORT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	348
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	349 // -------------------------------------------------------------------------
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	350 // Constructor
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	351
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	352 Cyg_SchedThread::Cyg_SchedThread(Cyg_Thread *thread, CYG_ADDRWORD sched_info)
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	353 : Cyg_SchedThread_Implementation(sched_info)
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	354 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	355 CYG_REPORT_FUNCTION();
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	356
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	357 queue = NULL;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	358
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	359 if( Cyg_Scheduler::current_thread == NULL )
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	360 Cyg_Scheduler::current_thread = thread;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	361
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	362 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	363
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	364 mutex_count = 0;
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	365
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	366 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_SIMPLE
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	367
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	368 priority_inherited = false;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	369
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	370 #endif
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	371 #endif
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	372
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	373 #ifdef CYGSEM_KERNEL_SCHED_ASR_SUPPORT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	374
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	375 asr_inhibit = false;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	376 asr_pending = false;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	377
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	378 #ifndef CYGSEM_KERNEL_SCHED_ASR_GLOBAL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	379 asr = asr_default;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	380 #endif
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	381 #ifdef CYGSEM_KERNEL_SCHED_ASR_DATA_GLOBAL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	382 asr_data = NULL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	383 #endif
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	384
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	385 #endif
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	386 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	387
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	388 // -------------------------------------------------------------------------
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	389 // ASR support functions
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	390
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	391 #ifdef CYGSEM_KERNEL_SCHED_ASR_SUPPORT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	392
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	393 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	394 // Set ASR
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	395 // Install a new ASR, returning the old one.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	396
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	397 void Cyg_SchedThread::set_asr( Cyg_ASR *new_asr, CYG_ADDRWORD new_data,
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	398 Cyg_ASR *old_asr, CYG_ADDRWORD old_data)
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	399 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	400 CYG_REPORT_FUNCTION();
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	401
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	402 // Do this with the scheduler locked...
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	403 Cyg_Scheduler::lock();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	404
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	405 if( old_asr != NULL ) *old_asr = asr;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	406 if( old_data != NULL ) *old_data = asr_data;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	407
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	408 // If new_asr is NULL, do not change the ASR,
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	409 // but only change the data.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	410 if( new_asr != NULL ) asr = new_asr;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	411 asr_data = new_data;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	412
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	413 Cyg_Scheduler::unlock();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	414 }
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	415
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	416 // -------------------------------------------------------------------------
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	417 // Clear ASR
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	418
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	419 void Cyg_SchedThread::clear_asr()
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	420 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	421 CYG_REPORT_FUNCTION();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	422
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	423 // Do this with the scheduler locked...
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	424 Cyg_Scheduler::lock();
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	425
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	426 // Reset ASR to default.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	427 asr = asr_default;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	428 asr_data = 0;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	429
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	430 Cyg_Scheduler::unlock();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	431 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	432
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	433 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	434 // Default ASR function.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	435 // having this avoids our having to worry about ever seeing a NULL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	436 // pointer as the ASR function.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	437
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	438 void Cyg_SchedThread::asr_default(CYG_ADDRWORD data)
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	439 {
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	440 CYG_REPORT_FUNCTION();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	441
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	442 data=data;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	443 return;
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	444 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	445
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	446 #endif
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	447
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	448 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	449 // Generic priority protocol support
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	450
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	451 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	452
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	453 void Cyg_SchedThread::set_inherited_priority( cyg_priority pri, Cyg_Thread *thread )
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	454 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	455 CYG_REPORT_FUNCTION();
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	456
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	457 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_SIMPLE
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	458
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	459 // This is the comon code for priority inheritance and ceiling
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	460 // protocols. This implementation provides a simplified version of
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	461 // the protocol.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	462
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	463 Cyg_Thread *self = CYG_CLASSFROMBASE(Cyg_Thread,
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	464 Cyg_SchedThread,
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	465 this);
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	466
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	467 CYG_ASSERT( mutex_count > 0, "Non-positive mutex count");
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	468
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	469 // Compare with current priority in case thread has already
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	470 // inherited - for relay case below.
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	471 if( pri < priority )
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	472 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	473 cyg_priority mypri = priority;
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	474 cyg_bool already_inherited = priority_inherited;
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	475
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	476 // If this is first inheritance, copy the old pri
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	477 // and set inherited flag. We clear it before setting the
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	478 // pri since set_priority() is inheritance aware.
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	479 // This is called with the sched locked, so no race conditions.
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	480
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	481 priority_inherited = false; // so that set_prio DTRT
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	482
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	483 self->set_priority( pri );
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	484
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	485 if( !already_inherited )
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	486 original_priority = mypri;
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	487
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	488 priority_inherited = true; // regardless, because it is now
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	489
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	490 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	491
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	492 #endif
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	493 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	494
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	495 void Cyg_SchedThread::relay_inherited_priority( Cyg_Thread ex_owner, Cyg_ThreadQueue pqueue)
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	496 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	497 CYG_REPORT_FUNCTION();
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	498
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	499 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_SIMPLE
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	500
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	501 // A simple implementation of priority inheritance.
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	502 // At its simplest, this member does nothing.
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	503
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	504 // If there is anyone else waiting, then the new owner inherits from
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	505 // the current one, since that is a maxima of the others waiting.
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	506 // (It's worth not doing if there's nobody waiting to prevent
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	507 // unneccessary priority skew.) This could be viewed as a discovered
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	508 // priority ceiling.
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	509
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	510 if ( !pqueue->empty() )
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	511 set_inherited_priority( ex_owner->get_current_priority(), ex_owner );
62 7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	512
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	513 #endif
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	514 }
7a6ac9edc838 Merge from eCos master repository on 2000-01-24-19:43:49-GMT jlarmour parents: 2 diff changeset	515
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	516 void Cyg_SchedThread::clear_inherited_priority()
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	517 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	518 CYG_REPORT_FUNCTION();
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	519
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	520 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_SIMPLE
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	521
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	522 // A simple implementation of priority inheritance/ceiling
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	523 // protocols. The simplification in this algorithm is that we do
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	524 // not reduce our priority until we have freed all mutexes
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	525 // claimed. Hence we can continue to run at an artificially high
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	526 // priority even when we should not. However, since nested
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	527 // mutexes are rare, the thread we have inherited from is likely
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	528 // to be locking the same mutexes we are, and mutex claim periods
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	529 // should be very short, the performance difference between this
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	530 // and a more complex algorithm should be negligible. The most
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	531 // important advantage of this algorithm is that it is fast and
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	532 // deterministic.
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	533
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	534 Cyg_Thread *self = CYG_CLASSFROMBASE(Cyg_Thread,
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	535 Cyg_SchedThread,
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	536 this);
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	537
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	538 CYG_ASSERT( mutex_count >= 0, "Non-positive mutex count");
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	539
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	540 if( mutex_count == 0 && priority_inherited )
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	541 {
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	542 priority_inherited = false;
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	543
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	544 // Only make an effort if the priority must change
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	545 if( priority < original_priority )
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	546 self->set_priority( original_priority );
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	547
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	548 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	549
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	550 #endif
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	551 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	552
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	553 #endif // CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	554
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	555 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	556 // Priority inheritance support.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	557
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	558 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_INHERIT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	559
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	560 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	561 // Inherit the priority of the provided thread if it
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	562 // has a higher priority than ours.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	563
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	564 void Cyg_SchedThread::inherit_priority( Cyg_Thread *thread)
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	565 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	566 CYG_REPORT_FUNCTION();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	567
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	568 Cyg_Thread *self = CYG_CLASSFROMBASE(Cyg_Thread,
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	569 Cyg_SchedThread,
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	570 this);
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	571
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	572 CYG_ASSERT( mutex_count > 0, "Non-positive mutex count");
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	573 CYG_ASSERT( self != thread, "Trying to inherit from self!");
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	574
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	575 self->set_inherited_priority( thread->get_current_priority(), thread );
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	576
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	577 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	578
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	579 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	580 // Inherit the priority of the ex-owner thread or from the queue if it
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	581 // has a higher priority than ours.
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	582
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	583 void Cyg_SchedThread::relay_priority( Cyg_Thread ex_owner, Cyg_ThreadQueue pqueue)
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	584 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	585 CYG_REPORT_FUNCTION();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	586
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	587 relay_inherited_priority( ex_owner, pqueue );
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	588 }
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	589
115 6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	590 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	591 // Lose a priority inheritance
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	592
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	593 void Cyg_SchedThread::disinherit_priority()
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	594 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	595 CYG_REPORT_FUNCTION();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	596
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	597 CYG_ASSERT( mutex_count >= 0, "Non-positive mutex count");
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	598
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	599 clear_inherited_priority();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	600 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	601
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	602 #endif // CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_INHERIT
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	603
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	604 // -------------------------------------------------------------------------
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	605 // Priority ceiling support
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	606
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	607 #ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_CEILING
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	608
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	609 void Cyg_SchedThread::set_priority_ceiling( cyg_priority pri )
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	610 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	611 CYG_REPORT_FUNCTION();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	612
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	613 CYG_ASSERT( mutex_count > 0, "Non-positive mutex count");
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	614
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	615 set_inherited_priority( pri );
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	616
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	617 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	618
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	619 void Cyg_SchedThread::clear_priority_ceiling( )
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	620 {
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	621 CYG_REPORT_FUNCTION();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	622
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	623 CYG_ASSERT( mutex_count >= 0, "Non-positive mutex count");
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	624
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	625 clear_inherited_priority();
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	626 }
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	627
6ed91473a1cd Merge from eCos master repository on 2000-08-21-22:40:54-BST jlarmour parents: 78 diff changeset	628 #endif // CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_CEILING
0 3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	629
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	630 // -------------------------------------------------------------------------
3111d98ba7b3 Initial commit of eCos version 1.1 jlarmour parents: diff changeset	631 // EOF sched/sched.cxx

Mercurial > ecos

annotate packages/kernel/current/src/sched/sched.cxx @ 115:6ed91473a1cd ecos-sw-2000-08-21