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Diffstat (limited to 'nuttx/sched/mq_waitirq.c')
| -rw-r--r-- | nuttx/sched/mq_waitirq.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/nuttx/sched/mq_waitirq.c b/nuttx/sched/mq_waitirq.c new file mode 100644 index 000000000..94a15df3c --- /dev/null +++ b/nuttx/sched/mq_waitirq.c @@ -0,0 +1,172 @@ +/**************************************************************************** + * sched/mq_waitirq.c + * + * Copyright (C) 2007-2009, 2011 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 <errno.h> + +#include <nuttx/arch.h> +#include <nuttx/mqueue.h> + +#include "os_internal.h" + +/**************************************************************************** + * Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Type Declarations + ****************************************************************************/ + +/**************************************************************************** + * Global Variables + ****************************************************************************/ + +/**************************************************************************** + * Private Variables + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: sem_waitirq + * + * Description: + * This function is called when a signal or a timeout is received by a + * task that is waiting on a message queue -- either for a queue to + * becoming not full (on mq_send) or not empty (on mq_receive). + * + * Parameters: + * wtcb - A pointer to the TCB of the task that is waiting on a message + * queue, but has received a signal instead. + * + * Return Value: + * None + * + * Assumptions: + * + ****************************************************************************/ + +void mq_waitirq(FAR _TCB *wtcb, int errcode) +{ + FAR msgq_t *msgq; + irqstate_t saved_state; + + /* Disable interrupts. This is necessary because an interrupt handler may + * attempt to send a message while we are doing this. + */ + + saved_state = irqsave(); + + /* It is possible that an interrupt/context switch beat us to the punch and + * already changed the task's state. NOTE: The operations within the if + * are safe because interrupts are always disabled with the msgwaitq, + * nwaitnotempty, and nwaitnotfull fields are modified. + */ + + if (wtcb->task_state == TSTATE_WAIT_MQNOTEMPTY || + wtcb->task_state == TSTATE_WAIT_MQNOTFULL) + { + /* Get the message queue associated with the waiter from the TCB */ + + msgq = wtcb->msgwaitq; +#ifdef CONFIG_DEBUG + if (!msgq) + { + /* In these states there must always be an associated message queue */ + + PANIC((uint32_t)OSERR_MQNOWAITER); + } +#endif + wtcb->msgwaitq = NULL; + + /* Decrement the count of waiters and cancel the wait */ + + if (wtcb->task_state == TSTATE_WAIT_MQNOTEMPTY) + { +#ifdef CONFIG_DEBUG + if (msgq->nwaitnotempty <= 0) + { + /* This state, there should be a positive, non-zero waiter + * count. + */ + + PANIC((uint32_t)OSERR_MQNONEMPTYCOUNT); + + } +#endif + msgq->nwaitnotempty--; + } + else + { +#ifdef CONFIG_DEBUG + if (msgq->nwaitnotfull <= 0) + { + /* This state, there should be a positive, non-zero waiter + * count. + */ + + PANIC((uint32_t)OSERR_MQNOTFULLCOUNT); + + } +#endif + msgq->nwaitnotfull--; + } + + /* Mark the errno value for the thread. */ + + wtcb->pterrno = errcode; + + /* Restart the task. */ + + up_unblock_task(wtcb); + } + + /* Interrupts may now be enabled. */ + + irqrestore(saved_state); +} + |