Decoupling work queue data structures. This is part of the preparation to support multiple low-priority worker threads

6 files changed, 194 insertions, 43 deletions

diff --git a/nuttx/libc/wqueue/work_cancel.c b/nuttx/libc/wqueue/work_cancel.c
index d3bcd0608..9484918c5 100644
--- a/nuttx/libc/wqueue/work_cancel.c
+++ b/nuttx/libc/wqueue/work_cancel.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/wqueue/work_cancel.c
  *
- *   Copyright (C) 2009-2010, 2012-2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009-2010, 2012-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -42,11 +42,12 @@
 #include <queue.h>
 #include <assert.h>
 #include <errno.h>
-#include <debug.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/wqueue.h>
 
+#include "wqueue/wqueue.h"
+
 #ifdef CONFIG_SCHED_WORKQUEUE
 
 /****************************************************************************
@@ -74,7 +75,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: work_cancel
+ * Name: work_qcancel
  *
  * Description:
  *   Cancel previously queued work.  This removes work from the work queue.
@@ -90,16 +91,16 @@
  *   reported:
  *
  *   -ENOENT - There is no such work queued.
+ *   -EINVAL - An invalid work queue was specified
  *
  ****************************************************************************/
 
-int work_cancel(int qid, FAR struct work_s *work)
+int work_qcancel(FAR struct wqueue_s *wqueue, FAR struct work_s *work)
 {
-  FAR struct wqueue_s *wqueue = &g_work[qid];
   irqstate_t flags;
   int ret = -ENOENT;
 
-  DEBUGASSERT(work != NULL && (unsigned)qid < NWORKERS);
+  DEBUGASSERT(work != NULL);
 
   /* Cancelling the work is simply a matter of removing the work structure
    * from the work queue.  This must be done with interrupts disabled because
@@ -115,7 +116,7 @@ int work_cancel(int qid, FAR struct work_s *work)
       DEBUGASSERT(work->dq.blink || (FAR dq_entry_t *)work == wqueue->q.head);
 
       /* Remove the entry from the work queue and make sure that it is
-       * mark as availalbe (i.e., the worker field is nullified).
+       * mark as available (i.e., the worker field is nullified).
        */
 
       dq_rem((FAR dq_entry_t *)work, &wqueue->q);
@@ -127,4 +128,39 @@ int work_cancel(int qid, FAR struct work_s *work)
   return ret;
 }
 
+/****************************************************************************
+ * Name: work_cancel
+ *
+ * Description:
+ *   Cancel previously queued user-mode work.  This removes work from the
+ *   user mode work queue.  After work has been cancelled, it may be re-queue
+ *   by calling work_queue() again.
+ *
+ * Input parameters:
+ *   qid    - The work queue ID (must be USRWORK)
+ *   work   - The previously queue work structure to cancel
+ *
+ * Returned Value:
+ *   Zero (OK) on success, a negated errno on failure.  This error may be
+ *   reported:
+ *
+ *   -ENOENT - There is no such work queued.
+ *
+ ****************************************************************************/
+
+#if defined(CONFIG_SCHED_USRWORK) && !defined(__KERNEL__)
+
+int work_cancel(int qid, FAR struct work_s *work)
+{
+  if (qid == USRWORK)
+    {
+      return work_qcancel(&g_usrwork, work);
+    }
+  else
+    {
+      return -EINVAL;
+    }
+}
+
+#endif /* CONFIG_SCHED_USRWORK && !__KERNEL__ */
 #endif /* CONFIG_SCHED_WORKQUEUE */
diff --git a/nuttx/libc/wqueue/work_process.c b/nuttx/libc/wqueue/work_process.c
index fb0ecfaa8..5171d6ff0 100644
--- a/nuttx/libc/wqueue/work_process.c
+++ b/nuttx/libc/wqueue/work_process.c
@@ -62,30 +62,6 @@
  * Public Data
  ****************************************************************************/
 
-/* The state of each work queue. */
-
-#ifdef CONFIG_BUILD_PROTECTED
-
-  /* Play some games in the kernel mode build to assure that different
-   * naming is used for the global work queue data structures.  This may
-   * not be necessary but it safer.
-   *
-   * In this case g_work is #define'd to be either g_kernelwork or
-   * g_usrwork in include/nuttx/wqueue.h
-   */
-
-#  ifdef __KERNEL__
-struct wqueue_s g_kernelwork[NWORKERS];
-#  else
-struct wqueue_s g_usrwork[NWORKERS];
-#  endif
-
-#else /* CONFIG_BUILD_PROTECTED */
-
-struct wqueue_s g_work[NWORKERS];
-
-#endif /* CONFIG_BUILD_PROTECTED */
-
 /****************************************************************************
  * Private Data
  ****************************************************************************/
diff --git a/nuttx/libc/wqueue/work_queue.c b/nuttx/libc/wqueue/work_queue.c
index c85f564e5..edfbb166e 100644
--- a/nuttx/libc/wqueue/work_queue.c
+++ b/nuttx/libc/wqueue/work_queue.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/wqueue/work_queue.c
  *
- *   Copyright (C) 2009-2011, 2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009-2011, 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -43,12 +43,13 @@
 #include <queue.h>
 #include <assert.h>
 #include <errno.h>
-#include <debug.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/clock.h>
 #include <nuttx/wqueue.h>
 
+#include "wqueue/wqueue.h"
+
 #ifdef CONFIG_SCHED_WORKQUEUE
 
 /****************************************************************************
@@ -76,7 +77,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: work_queue
+ * Name: work_qqueue
  *
  * Description:
  *   Queue work to be performed at a later time.  All queued work will be
@@ -104,13 +105,12 @@
  *
  ****************************************************************************/
 
-int work_queue(int qid, FAR struct work_s *work, worker_t worker,
-               FAR void *arg, uint32_t delay)
+int work_qqueue(FAR struct wqueue_s *wqueue, FAR struct work_s *work,
+                worker_t worker, FAR void *arg, uint32_t delay)
 {
-  FAR struct wqueue_s *wqueue = &g_work[qid];
   irqstate_t flags;
 
-  DEBUGASSERT(work != NULL && (unsigned)qid < NWORKERS);
+  DEBUGASSERT(work != NULL);
 
   /* First, initialize the work structure */
 
@@ -133,4 +133,49 @@ int work_queue(int qid, FAR struct work_s *work, worker_t worker,
   return OK;
 }
 
+/****************************************************************************
+ * Name: work_queue
+ *
+ * Description:
+ *   Queue user-mode work to be performed at a later time.  All queued work
+ *   will be performed on the worker thread of of execution (not the caller's).
+ *
+ *   The work structure is allocated by caller, but completely managed by
+ *   the work queue logic.  The caller should never modify the contents of
+ *   the work queue structure; the caller should not call work_queue()
+ *   again until either (1) the previous work has been performed and removed
+ *   from the queue, or (2) work_cancel() has been called to cancel the work
+ *   and remove it from the work queue.
+ *
+ * Input parameters:
+ *   qid    - The work queue ID (index)
+ *   work   - The work structure to queue
+ *   worker - The worker callback to be invoked.  The callback will invoked
+ *            on the worker thread of execution.
+ *   arg    - The argument that will be passed to the workder callback when
+ *            int is invoked.
+ *   delay  - Delay (in clock ticks) from the time queue until the worker
+ *            is invoked. Zero means to perform the work immediately.
+ *
+ * Returned Value:
+ *   Zero on success, a negated errno on failure
+ *
+ ****************************************************************************/
+
+#if defined(CONFIG_SCHED_USRWORK) && !defined(__KERNEL__)
+
+int work_queue(int qid, FAR struct work_s *work, worker_t worker,
+               FAR void *arg, uint32_t delay)
+{
+  if (qid == USRWORK)
+    {
+      return work_qqueue(&g_usrwork, work, worker, arg, delay);
+    }
+  else
+    {
+      return -EINVAL;
+    }
+}
+
+#endif /* CONFIG_SCHED_USRWORK && !__KERNEL__ */
 #endif /* CONFIG_SCHED_WORKQUEUE */
diff --git a/nuttx/libc/wqueue/work_signal.c b/nuttx/libc/wqueue/work_signal.c
index d7459cb97..2d6b9e238 100644
--- a/nuttx/libc/wqueue/work_signal.c
+++ b/nuttx/libc/wqueue/work_signal.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/wqueue/work_signal.c
  *
- *   Copyright (C) 2009-2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -40,10 +40,11 @@
 #include <nuttx/config.h>
 
 #include <signal.h>
-#include <assert.h>
 
 #include <nuttx/wqueue.h>
 
+#include "wqueue/wqueue.h"
+
 #ifdef CONFIG_SCHED_WORKQUEUE
 
 /****************************************************************************
@@ -85,10 +86,28 @@
  *
  ****************************************************************************/
 
+#if defined(CONFIG_SCHED_USRWORK) && !defined(__KERNEL__)
+
 int work_signal(int qid)
 {
-  DEBUGASSERT((unsigned)qid < NWORKERS);
-  return kill(g_work[qid].pid, SIGWORK);
+  int ret;
+
+  if (qid == USRWORK)
+    {
+      /* Signal the worker thread */
+
+      ret = kill(g_usrwork.pid, SIGWORK);
+      if (ret < 0)
+        {
+          int errcode = errno;
+          return -errcode;
+        }
+    }
+  else
+    {
+      return -EINVAL;
+    }
 }
 
+#endif /* CONFIG_SCHED_USRWORK && !__KERNEL__ */
 #endif /* CONFIG_SCHED_WORKQUEUE */
diff --git a/nuttx/libc/wqueue/work_usrthread.c b/nuttx/libc/wqueue/work_usrthread.c
index b836e27ca..f46924a06 100644
--- a/nuttx/libc/wqueue/work_usrthread.c
+++ b/nuttx/libc/wqueue/work_usrthread.c
@@ -48,6 +48,10 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
+/* The state of the user mode work queue. */
+
+extern struct wqueue_s g_usrwork;
+
 /****************************************************************************
  * Private Type Declarations
  ****************************************************************************/
@@ -93,7 +97,7 @@ int work_usrthread(int argc, char *argv[])
        * we process items in the work list.
        */
 
-      work_process(&g_work[USRWORK]);
+      work_process(&g_usrwork);
     }
 
   return OK; /* To keep some compilers happy */
diff --git a/nuttx/libc/wqueue/wqueue.h b/nuttx/libc/wqueue/wqueue.h
new file mode 100644
index 000000000..9f6d2dde5
--- /dev/null
+++ b/nuttx/libc/wqueue/wqueue.h
@@ -0,0 +1,71 @@
+/****************************************************************************
+ * sched/libc/wqueue.h
+ *
+ *   Copyright (C) 2014 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.
+ *
+ ****************************************************************************/
+
+#ifndef __LIBC_WQUEUE_WQUEUE_H
+#define __LIBC_WQUEUE_WQUEUE_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#ifdef CONFIG_SCHED_WORKQUEUE
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Type Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#if defined(CONFIG_SCHED_USRWORK) && !defined(__KERNEL__)
+
+/* The state of the user mode work queue */
+
+extern struct wqueue_s g_usrwork;
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#endif /* CONFIG_SCHED_WORKQUEUE */
+#endif /* __LIBC_WQUEUE_WQUEUE_H */