alf_task_depends

NAME

alf_task_depends_on - Describes a relationship between two tasks.

SYNOPSIS

int alf_task_depends_on (alf_task_handle_t task_handle_dependent, alf_task_handle_t task_handle);

Parameters
`task_handle_dependent [IN]`	The handle to the dependent task
`task_handle [IN]`	The handle to a task

DESCRIPTION

This function describes a relationship between two tasks. The task specified by task_handle_dependent cannot be scheduled to run until the task specified by task_handle has run to finish normally. When this API is called, task_handle must not be an explicitly destroyed task. An error is reported if it is the case. If the task associated with task_handle is destroyed before normal completion, the task_handle_dependent is also destroyed because its dependency can no longer be satisfied.

If task A depends on task B, a call to alf_task_wait (A_handle) effectively enforces a wait on task B as well. A duplicate dependency is handled silently and not treated as an error.

Note: This function can only be called before any work blocks are enqueued to the task_handle_dependent and before the task_handle_dependent is finalized. For the task_handle, these constraint is not applicable.

Whenever a situation occurs that is not permitted, the function returns ALF_ERR_PERM.

RETURN VALUE

0	Success
less than 0	Errors occurred: `ALF_ERR_BADF`: Invalid task handle. `ALF_ERR_PERM`: The API call is not permitted at the current context. For example, the dependency cannot be set because of the current state of the task. `ALF_ERR_GENERIC`: Generic internal errors.