1 files changed, 114 insertions, 0 deletions
diff --git a/nuttx/sched/sched_free.c b/nuttx/sched/sched_free.c
new file mode 100644
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+/************************************************************************
+ * sched/sched_free.c
+ *
+ *   Copyright (C) 2007, 2009 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 <queue.h>
+#include <assert.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/arch.h>
+#include <nuttx/wqueue.h>
+#include "os_internal.h"
+
+/************************************************************************
+ * Definitions
+ ************************************************************************/
+
+/************************************************************************
+ * Private Type Declarations
+ ************************************************************************/
+
+/************************************************************************
+ * Global Variables
+ ************************************************************************/
+
+/************************************************************************
+ * Private Variables
+ ************************************************************************/
+
+/************************************************************************
+ * Private Function Prototypes
+ ************************************************************************/
+
+/************************************************************************
+ * Public Functions
+ ************************************************************************/
+
+/************************************************************************
+ * Name: sched_free
+ *
+ * Description:
+ *   This function performs deallocations that the operating system may
+ *   need to make.  This special interface to free is used to handling
+ *   corner cases where the operating system may have to perform
+ *   deallocations from within an interrupt handler.
+ *
+ ************************************************************************/
+
+void sched_free(FAR void *address)
+{
+  /* Check if this is an attempt to deallocate memory from an exception
+   * handler.  If this function is called from the IDLE task, then we
+   * must have exclusive access to the memory manager to do this.
+   */
+
+  if (up_interrupt_context() || kmm_trysemaphore() != 0)
+    {
+      /* Yes.. Delay the deallocation until a more appropriate time. */
+
+      irqstate_t saved_state = irqsave();
+      sq_addlast((FAR sq_entry_t*)address, (sq_queue_t*)&g_delayeddeallocations);
+
+      /* Signal the worker thread that is has some clean up to do */
+
+#ifdef CONFIG_SCHED_WORKQUEUE
+      work_signal();
+#endif
+      irqrestore(saved_state);
+    }
+  else
+    {
+      /* No.. just deallocate the memory now. */
+
+      kfree(address);
+      kmm_givesemaphore();
+    }
+}
+