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Diffstat (limited to 'nuttx/sched/group_join.c')
-rw-r--r-- | nuttx/sched/group_join.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/nuttx/sched/group_join.c b/nuttx/sched/group_join.c new file mode 100644 index 000000000..987c1ba87 --- /dev/null +++ b/nuttx/sched/group_join.c @@ -0,0 +1,107 @@ +/***************************************************************************** + * sched/group_join.c + * + * Copyright (C) 2013 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 <assert.h> +#include <debug.h> + +#include "os_internal.h" + +#ifdef HAVE_TASK_GROUP + +/***************************************************************************** + * Pre-processor Definitions + *****************************************************************************/ + +/***************************************************************************** + * Private Types + *****************************************************************************/ + +/***************************************************************************** + * Private Data + *****************************************************************************/ + +/***************************************************************************** + * Private Functions + *****************************************************************************/ + +/***************************************************************************** + * Public Functions + *****************************************************************************/ + +/***************************************************************************** + * Name: group_join + * + * Description: + * Copy the group structure reference from one TCB to another, incrementing + * the refrence count on the group. This function is called when a pthread + * is produced within the task group so that the pthread can share the + * resources of the task group. + * + * Parameters: + * tcb - The TCB of the new "child" task that need to join the group. + * + * Return Value: + * None + * + * Assumptions: + * - The parent task from which the group will be inherited is the task at + * the thead of the ready to run list. + * - Called during thread creation in a safe context. No special precautions + * are required here. + * + *****************************************************************************/ + +void group_join(FAR _TCB *tcb) +{ + FAR _TCB *ptcb = (FAR _TCB *)g_readytorun.head; + + DEBUGASSERT(ptcb && tcb && ptcb->group && !tcb->group); + + /* Copy the group reference from the parent to the child, incrementing the + * reference count. + */ + + tcb->group = ptcb->group; + ptcb->group->tg_crefs++; +} + +#endif /* HAVE_TASK_GROUP */ |