b48009644f
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5610 42af7a65-404d-4744-a932-0658087f49c3
188 lines
6.5 KiB
C
188 lines
6.5 KiB
C
/****************************************************************************
|
|
* arch/hc/src/common/up_reprioritizertr.c
|
|
*
|
|
* Copyright (C) 2010, 2013 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <gnutt@nuttx.org>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* 3. Neither the name NuttX nor the names of its contributors may be
|
|
* used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
#include <stdint.h>
|
|
#include <stdbool.h>
|
|
#include <sched.h>
|
|
#include <debug.h>
|
|
#include <nuttx/arch.h>
|
|
|
|
#include "os_internal.h"
|
|
#include "up_internal.h"
|
|
|
|
/****************************************************************************
|
|
* Pre-processor Definitions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Data
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: up_reprioritize_rtr
|
|
*
|
|
* Description:
|
|
* Called when the priority of a running or
|
|
* ready-to-run task changes and the reprioritization will
|
|
* cause a context switch. Two cases:
|
|
*
|
|
* 1) The priority of the currently running task drops and the next
|
|
* task in the ready to run list has priority.
|
|
* 2) An idle, ready to run task's priority has been raised above the
|
|
* the priority of the current, running task and it now has the
|
|
* priority.
|
|
*
|
|
* Inputs:
|
|
* tcb: The TCB of the task that has been reprioritized
|
|
* priority: The new task priority
|
|
*
|
|
****************************************************************************/
|
|
|
|
void up_reprioritize_rtr(struct tcb_s *tcb, uint8_t priority)
|
|
{
|
|
/* Verify that the caller is sane */
|
|
|
|
if (tcb->task_state < FIRST_READY_TO_RUN_STATE ||
|
|
tcb->task_state > LAST_READY_TO_RUN_STATE
|
|
#if SCHED_PRIORITY_MIN > 0
|
|
|| priority < SCHED_PRIORITY_MIN
|
|
#endif
|
|
#if SCHED_PRIORITY_MAX < UINT8_MAX
|
|
|| priority > SCHED_PRIORITY_MAX
|
|
#endif
|
|
)
|
|
{
|
|
PANIC(OSERR_BADREPRIORITIZESTATE);
|
|
}
|
|
else
|
|
{
|
|
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
|
|
bool switch_needed;
|
|
|
|
slldbg("TCB=%p PRI=%d\n", tcb, priority);
|
|
|
|
/* Remove the tcb task from the ready-to-run list.
|
|
* sched_removereadytorun will return true if we just
|
|
* remove the head of the ready to run list.
|
|
*/
|
|
|
|
switch_needed = sched_removereadytorun(tcb);
|
|
|
|
/* Setup up the new task priority */
|
|
|
|
tcb->sched_priority = (uint8_t)priority;
|
|
|
|
/* Return the task to the specified blocked task list.
|
|
* sched_addreadytorun will return true if the task was
|
|
* added to the new list. We will need to perform a context
|
|
* switch only if the EXCLUSIVE or of the two calls is non-zero
|
|
* (i.e., one and only one the calls changes the head of the
|
|
* ready-to-run list).
|
|
*/
|
|
|
|
switch_needed ^= sched_addreadytorun(tcb);
|
|
|
|
/* Now, perform the context switch if one is needed */
|
|
|
|
if (switch_needed)
|
|
{
|
|
/* If we are going to do a context switch, then now is the right
|
|
* time to add any pending tasks back into the ready-to-run list.
|
|
* task list now
|
|
*/
|
|
|
|
if (g_pendingtasks.head)
|
|
{
|
|
sched_mergepending();
|
|
}
|
|
|
|
/* Are we in an interrupt handler? */
|
|
|
|
if (current_regs)
|
|
{
|
|
/* Yes, then we have to do things differently.
|
|
* Just copy the current_regs into the OLD rtcb.
|
|
*/
|
|
|
|
up_savestate(rtcb->xcp.regs);
|
|
|
|
/* Restore the exception context of the rtcb at the (new) head
|
|
* of the g_readytorun task list.
|
|
*/
|
|
|
|
rtcb = (struct tcb_s*)g_readytorun.head;
|
|
slldbg("New Active Task TCB=%p\n", rtcb);
|
|
|
|
/* Then switch contexts */
|
|
|
|
up_restorestate(rtcb->xcp.regs);
|
|
}
|
|
|
|
/* Copy the exception context into the TCB at the (old) head of the
|
|
* g_readytorun Task list. if up_saveusercontext returns a non-zero
|
|
* value, then this is really the previously running task restarting!
|
|
*/
|
|
|
|
else if (!up_saveusercontext(rtcb->xcp.regs))
|
|
{
|
|
/* Restore the exception context of the rtcb at the (new) head
|
|
* of the g_readytorun task list.
|
|
*/
|
|
|
|
rtcb = (struct tcb_s*)g_readytorun.head;
|
|
slldbg("New Active Task TCB=%p\n", rtcb);
|
|
|
|
/* Then switch contexts */
|
|
|
|
up_fullcontextrestore(rtcb->xcp.regs);
|
|
}
|
|
}
|
|
}
|
|
}
|