9c89c16a7c
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3846 42af7a65-404d-4744-a932-0658087f49c3
209 lines
7.8 KiB
C
209 lines
7.8 KiB
C
/****************************************************************************
|
|
* arch/arm/src/armv7-m/up_schedulesigaction.c
|
|
*
|
|
* Copyright (C) 2009-2011 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
|
|
*
|
|
* 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 <sched.h>
|
|
#include <debug.h>
|
|
|
|
#include <nuttx/arch.h>
|
|
|
|
#include "psr.h"
|
|
#include "os_internal.h"
|
|
#include "up_internal.h"
|
|
#include "up_arch.h"
|
|
|
|
#ifndef CONFIG_DISABLE_SIGNALS
|
|
|
|
/****************************************************************************
|
|
* Pre-processor Definitions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Data
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: up_schedule_sigaction
|
|
*
|
|
* Description:
|
|
* This function is called by the OS when one or more
|
|
* signal handling actions have been queued for execution.
|
|
* The architecture specific code must configure things so
|
|
* that the 'igdeliver' callback is executed on the thread
|
|
* specified by 'tcb' as soon as possible.
|
|
*
|
|
* This function may be called from interrupt handling logic.
|
|
*
|
|
* This operation should not cause the task to be unblocked
|
|
* nor should it cause any immediate execution of sigdeliver.
|
|
* Typically, a few cases need to be considered:
|
|
*
|
|
* (1) This function may be called from an interrupt handler
|
|
* During interrupt processing, all xcptcontext structures
|
|
* should be valid for all tasks. That structure should
|
|
* be modified to invoke sigdeliver() either on return
|
|
* from (this) interrupt or on some subsequent context
|
|
* switch to the recipient task.
|
|
* (2) If not in an interrupt handler and the tcb is NOT
|
|
* the currently executing task, then again just modify
|
|
* the saved xcptcontext structure for the recipient
|
|
* task so it will invoke sigdeliver when that task is
|
|
* later resumed.
|
|
* (3) If not in an interrupt handler and the tcb IS the
|
|
* currently executing task -- just call the signal
|
|
* handler now.
|
|
*
|
|
****************************************************************************/
|
|
|
|
void up_schedule_sigaction(_TCB *tcb, sig_deliver_t sigdeliver)
|
|
{
|
|
/* Refuse to handle nested signal actions */
|
|
|
|
sdbg("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
|
|
|
|
if (!tcb->xcp.sigdeliver)
|
|
{
|
|
irqstate_t flags;
|
|
|
|
/* Make sure that interrupts are disabled */
|
|
|
|
flags = irqsave();
|
|
|
|
/* First, handle some special cases when the signal is
|
|
* being delivered to the currently executing task.
|
|
*/
|
|
|
|
sdbg("rtcb=0x%p current_regs=0x%p\n", g_readytorun.head, current_regs);
|
|
|
|
if (tcb == (_TCB*)g_readytorun.head)
|
|
{
|
|
/* CASE 1: We are not in an interrupt handler and
|
|
* a task is signalling itself for some reason.
|
|
*/
|
|
|
|
if (!current_regs)
|
|
{
|
|
/* In this case just deliver the signal now. */
|
|
|
|
sigdeliver(tcb);
|
|
}
|
|
|
|
/* CASE 2: We are in an interrupt handler AND the
|
|
* interrupted task is the same as the one that
|
|
* must receive the signal, then we will have to modify
|
|
* the return state as well as the state in the TCB.
|
|
*
|
|
* Hmmm... there looks like a latent bug here: The following
|
|
* logic would fail in the strange case where we are in an
|
|
* interrupt handler, the thread is signalling itself, but
|
|
* a context switch to another task has occurred so that
|
|
* current_regs does not refer to the thread at g_readytorun.head!
|
|
*/
|
|
|
|
else
|
|
{
|
|
/* Save the return lr and cpsr and one scratch register
|
|
* These will be restored by the signal trampoline after
|
|
* the signals have been delivered.
|
|
*/
|
|
|
|
tcb->xcp.sigdeliver = sigdeliver;
|
|
tcb->xcp.saved_pc = current_regs[REG_PC];
|
|
tcb->xcp.saved_primask = current_regs[REG_PRIMASK];
|
|
tcb->xcp.saved_xpsr = current_regs[REG_XPSR];
|
|
|
|
/* Then set up to vector to the trampoline with interrupts
|
|
* disabled
|
|
*/
|
|
|
|
current_regs[REG_PC] = (uint32_t)up_sigdeliver;
|
|
current_regs[REG_PRIMASK] = 1;
|
|
current_regs[REG_XPSR] = ARMV7M_XPSR_T;
|
|
|
|
/* And make sure that the saved context in the TCB
|
|
* is the same as the interrupt return context.
|
|
*/
|
|
|
|
up_savestate(tcb->xcp.regs);
|
|
}
|
|
}
|
|
|
|
/* Otherwise, we are (1) signaling a task is not running
|
|
* from an interrupt handler or (2) we are not in an
|
|
* interrupt handler and the running task is signalling
|
|
* some non-running task.
|
|
*/
|
|
|
|
else
|
|
{
|
|
/* Save the return lr and cpsr and one scratch register
|
|
* These will be restored by the signal trampoline after
|
|
* the signals have been delivered.
|
|
*/
|
|
|
|
tcb->xcp.sigdeliver = sigdeliver;
|
|
tcb->xcp.saved_pc = tcb->xcp.regs[REG_PC];
|
|
tcb->xcp.saved_primask = tcb->xcp.regs[REG_PRIMASK];
|
|
tcb->xcp.saved_xpsr = tcb->xcp.regs[REG_XPSR];
|
|
|
|
/* Then set up to vector to the trampoline with interrupts
|
|
* disabled
|
|
*/
|
|
|
|
tcb->xcp.regs[REG_PC] = (uint32_t)up_sigdeliver;
|
|
tcb->xcp.regs[REG_PRIMASK] = 1;
|
|
tcb->xcp.regs[REG_XPSR] = ARMV7M_XPSR_T;
|
|
}
|
|
|
|
irqrestore(flags);
|
|
}
|
|
}
|
|
|
|
#endif /* !CONFIG_DISABLE_SIGNALS */
|