Add task init and signal scheduling logic

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3338 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 139 insertions, 0 deletions

diff --git a/nuttx/arch/x86/src/i486/up_sigdeliver.c b/nuttx/arch/x86/src/i486/up_sigdeliver.c
new file mode 100644
index 000000000..839943bcc
--- /dev/null
+++ b/nuttx/arch/x86/src/i486/up_sigdeliver.c
@@ -0,0 +1,139 @@
+/****************************************************************************
+ * arch/x86/src/i486/up_sigdeliver.c
+ *
+ *   Copyright (C) 2010 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/irq.h>
+#include <nuttx/arch.h>
+#include <arch/board/board.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_sigdeliver
+ *
+ * Description:
+ *   This is the a signal handling trampoline.  When a signal action was
+ *   posted.  The task context was mucked with and forced to branch to this
+ *   location with interrupts disabled.
+ *
+ ****************************************************************************/
+
+void up_sigdeliver(void)
+{
+  _TCB  *rtcb = (_TCB*)g_readytorun.head;
+  uint32_t regs[XCPTCONTEXT_REGS];
+  sig_deliver_t sigdeliver;
+
+  /* Save the errno.  This must be preserved throughout the signal handling
+   * so that the user code final gets the correct errno value (probably
+   * EINTR).
+   */
+
+  int saved_errno = rtcb->pterrno;
+
+  up_ledon(LED_SIGNAL);
+
+  sdbg("rtcb=%p sigdeliver=%p sigpendactionq.head=%p\n",
+        rtcb, rtcb->xcp.sigdeliver, rtcb->sigpendactionq.head);
+  ASSERT(rtcb->xcp.sigdeliver != NULL);
+
+  /* Save the real return state on the stack. */
+
+  up_copystate(regs, rtcb->xcp.regs);
+  regs[REG_PC]         = rtcb->xcp.saved_pc;
+  regs[REG_FLAGS]      = rtcb->xcp.saved_flags;
+
+  /* Get a local copy of the sigdeliver function pointer. we do this so that
+   * we can nullify the sigdeliver function pointer in the TCB and accept
+   * more signal deliveries while processing the current pending signals.
+   */
+
+  sigdeliver           = rtcb->xcp.sigdeliver;
+  rtcb->xcp.sigdeliver = NULL;
+
+  /* Then restore the task interrupt state */
+
+  irqrestore(regs[REG_FLAGS]);
+
+  /* Deliver the signals */
+
+  sigdeliver(rtcb);
+
+  /* Output any debug messages BEFORE restoring errno (because they may
+   * alter errno), then disable interrupts again and restore the original
+   * errno that is needed by the user logic (it is probably EINTR).
+   */
+
+  sdbg("Resuming\n");
+  (void)irqsave();
+  rtcb->pterrno = saved_errno;
+
+  /* Then restore the correct state for this thread of execution. */
+
+  up_ledoff(LED_SIGNAL);
+  up_fullcontextrestore(regs);
+}
+
+#endif /* !CONFIG_DISABLE_SIGNALS */
+