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author | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2013-01-25 19:15:05 +0000 |
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committer | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2013-01-25 19:15:05 +0000 |
commit | 80904539e63681b2dca74e3978effb17f0c071b0 (patch) | |
tree | eb49c2f705d2255cc6f05a7ee433aa87472c8a88 /nuttx/sched/group_create.c | |
parent | e95efd5d2a08dcb62c8c635089e4fe146965db45 (diff) | |
download | px4-firmware-80904539e63681b2dca74e3978effb17f0c071b0.tar.gz px4-firmware-80904539e63681b2dca74e3978effb17f0c071b0.tar.bz2 px4-firmware-80904539e63681b2dca74e3978effb17f0c071b0.zip |
Add logic to keep track of members of a task group
git-svn-id: http://svn.code.sf.net/p/nuttx/code/trunk@5563 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/sched/group_create.c')
-rw-r--r-- | nuttx/sched/group_create.c | 74 |
1 files changed, 62 insertions, 12 deletions
diff --git a/nuttx/sched/group_create.c b/nuttx/sched/group_create.c index d036b9084..4612ae8c5 100644 --- a/nuttx/sched/group_create.c +++ b/nuttx/sched/group_create.c @@ -1,5 +1,5 @@ /***************************************************************************** - * sched/group_create.c + * sched/group_allocate.c * * Copyright (C) 2013 Gregory Nutt. All rights reserved. * Author: Gregory Nutt <gnutt@nuttx.org> @@ -51,6 +51,9 @@ /***************************************************************************** * Pre-processor Definitions *****************************************************************************/ +/* Is this worth making a configuration option? */ + +#define GROUP_INITIAL_MEMBERS 4 /***************************************************************************** * Private Types @@ -69,11 +72,16 @@ *****************************************************************************/ /***************************************************************************** - * Name: group_create + * Name: group_allocate * * Description: - * Create and initialize a new task group structure for the specified TCB. - * This function is called as part of the task creation sequence. + * Create and a new task group structure for the specified TCB. This + * function is called as part of the task creation sequence. The structure + * allocated and zered, but otherwise uninitialized. The full creation + * of the group of a two step process: (1) First, this function allocates + * group structure early in the task creation sequence in order to provide a + * group container, then (2) group_initialize() is called to set up the + * group membership. * * Parameters: * tcb - The tcb in need of the task group. @@ -87,24 +95,66 @@ * *****************************************************************************/ -int group_create(FAR _TCB *tcb) +int group_allocate(FAR _TCB *tcb) { + DEBUGASSERT(tcb && !tcb->group); + + /* Allocate the group structure and assign it to the TCB */ + + tcb->group = (FAR struct task_group_s *)kzalloc(sizeof(struct task_group_s)); + return tcb->group ? OK : -ENOMEM; +} + +/***************************************************************************** + * Name: group_initialize + * + * Description: + * Add the task as the initial member of the group. The full creation of + * the group of a two step process: (1) First, this group structure is + * allocated by group_allocate() early in the task creation sequence, then + * (2) this function is called to set up the initial group membership. + * + * Parameters: + * tcb - The tcb in need of the task group. + * + * Return Value: + * 0 (OK) on success; a negated errno value on failure. + * + * Assumptions: + * Called during task creation in a safe context. No special precautions + * are required here. + * + *****************************************************************************/ + +int group_initialize(FAR _TCB *tcb) +{ +#ifdef HAVE_GROUP_MEMBERS FAR struct task_group_s *group; - DEBUGASSERT(tcb && !tcb->group); + DEBUGASSERT(tcb && tcb->group); + group = tcb->group; - /* Allocate the group structure */ + /* Allocate space to hold GROUP_INITIAL_MEMBERS members of the group */ - group = (FAR struct task_group_s *)kzalloc(sizeof(struct task_group_s)); - if (!group) + group->tg_members = (FAR pid_t *)kmalloc(GROUP_INITIAL_MEMBERS*sizeof(pid_t)); + if (!group->tg_members) { + free(group); return -ENOMEM; } - /* Initialize the group structure and assign it to the tcb */ + /* Assign the PID of this new task as a member of the group*/ + + group->tg_members[0] = tcb->pid; + + /* Initialize the non-zero elements of group structure and assign it to + * the tcb. + */ + + group->tg_mxmembers = GROUP_INITIAL_MEMBERS; /* Number of members in allocation */ +#endif - group->tg_crefs = 1; - tcb->group = group; + group->tg_nmembers = 1; /* Number of members in the group */ return OK; } |