diff options
author | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2013-02-16 16:32:19 +0000 |
---|---|---|
committer | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2013-02-16 16:32:19 +0000 |
commit | b78eb3e4bbd9a44cb38e6cd5f7fdde4e22a183f4 (patch) | |
tree | 82e3a9b70e21bda79f4a26bf36dd755dcb4160a9 /nuttx/arch/arm/src/armv6-m/up_unblocktask.c | |
parent | 54c9fa75c9466f4676d12105dbf4026aeb92adb7 (diff) | |
download | px4-nuttx-b78eb3e4bbd9a44cb38e6cd5f7fdde4e22a183f4.tar.gz px4-nuttx-b78eb3e4bbd9a44cb38e6cd5f7fdde4e22a183f4.tar.bz2 px4-nuttx-b78eb3e4bbd9a44cb38e6cd5f7fdde4e22a183f4.zip |
First cut at support for Cortex-M0
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5655 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/arch/arm/src/armv6-m/up_unblocktask.c')
-rw-r--r-- | nuttx/arch/arm/src/armv6-m/up_unblocktask.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/armv6-m/up_unblocktask.c b/nuttx/arch/arm/src/armv6-m/up_unblocktask.c new file mode 100644 index 000000000..c496a8f43 --- /dev/null +++ b/nuttx/arch/arm/src/armv6-m/up_unblocktask.c @@ -0,0 +1,156 @@ +/**************************************************************************** + * arch/arm/src/armv6-m/up_unblocktask.c + * + * Copyright (C) 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 <sched.h> +#include <debug.h> +#include <nuttx/arch.h> + +#include "os_internal.h" +#include "clock_internal.h" +#include "up_internal.h" + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: up_unblock_task + * + * Description: + * A task is currently in an inactive task list but has been prepped to + * execute. Move the TCB to the ready-to-run list, restore its context, + * and start execution. + * + * Inputs: + * tcb: Refers to the tcb to be unblocked. This tcb is in one of the + * waiting tasks lists. It must be moved to the ready-to-run list and, + * if it is the highest priority ready to run taks, executed. + * + ****************************************************************************/ + +void up_unblock_task(struct tcb_s *tcb) +{ + /* Verify that the context switch can be performed */ + + if ((tcb->task_state < FIRST_BLOCKED_STATE) || + (tcb->task_state > LAST_BLOCKED_STATE)) + { + PANIC(OSERR_BADUNBLOCKSTATE); + } + else + { + struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head; + + /* Remove the task from the blocked task list */ + + sched_removeblocked(tcb); + + /* Reset its timeslice. This is only meaningful for round + * robin tasks but it doesn't here to do it for everything + */ + +#if CONFIG_RR_INTERVAL > 0 + tcb->timeslice = CONFIG_RR_INTERVAL / MSEC_PER_TICK; +#endif + + /* Add the task in the correct location in the prioritized + * g_readytorun task list + */ + + if (sched_addreadytorun(tcb)) + { + /* The currently active task has changed! We need to do + * a context switch to the new task. + * + * 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; + + /* Then switch contexts */ + + up_restorestate(rtcb->xcp.regs); + } + + /* No, then we will need to perform the user context switch */ + + else + { + /* Switch context to the context of the task at the head of the + * ready to run list. + */ + + struct tcb_s *nexttcb = (struct tcb_s*)g_readytorun.head; + up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs); + + /* up_switchcontext forces a context switch to the task at the + * head of the ready-to-run list. It does not 'return' in the + * normal sense. When it does return, it is because the blocked + * task is again ready to run and has execution priority. + */ + } + } + } +} |