diff options
author | Joel Sherrill <joel.sherrill@OARcorp.com> | 2006-09-07 18:07:53 +0000 |
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committer | Joel Sherrill <joel.sherrill@OARcorp.com> | 2006-09-07 18:07:53 +0000 |
commit | 03ef051fb5b77ab0010818a0de805b01ba9b59ab (patch) | |
tree | 64bf156abe3913a993a7e92c94b6b00222276d00 | |
parent | 77e75c79ab2adfd44de441a09464b0ae4eb306b5 (diff) |
2006-09-07 Ken Peters <ken.peters@jpl.nasa.gov>
PR 1171/doc
* timer.t: Correct documentation for rtems_timer_initiate_server.
-rw-r--r-- | doc/user/ChangeLog | 5 | ||||
-rw-r--r-- | doc/user/timer.t | 10 |
2 files changed, 12 insertions, 3 deletions
diff --git a/doc/user/ChangeLog b/doc/user/ChangeLog index d0070e9857..9adb590e6a 100644 --- a/doc/user/ChangeLog +++ b/doc/user/ChangeLog @@ -1,3 +1,8 @@ +2006-09-07 Ken Peters <ken.peters@jpl.nasa.gov> + + PR 1171/doc + * timer.t: Correct documentation for rtems_timer_initiate_server. + 2004-11-05 Joel Sherrill <joel@OARcorp.com> PR 706/doc diff --git a/doc/user/timer.t b/doc/user/timer.t index 421fc4f032..88c59d7306 100644 --- a/doc/user/timer.t +++ b/doc/user/timer.t @@ -60,7 +60,8 @@ sometimes referred to as a "keep alive" or a "deadman" timer. The Timer Server task is responsible for executing the timer service routines associated with all task-based timers. This task executes at a priority higher than any RTEMS application -task and thus can be viewed logically as the lowest priority interrupt. +task, and is created non-preemptible, and thus can be viewed logically as +the lowest priority interrupt. By providing a mechanism where timer service routines execute in task rather than interrupt space, the application is @@ -70,7 +71,9 @@ can be configured to have a floating point context in which case it would be save to perform floating point operations from a task-based timer. Most of the time, executing floating point instructions from an interrupt service routine -is not considered safe. +is not considered safe. However, since the Timer Server task +is non-preemptible, only directives allowed from an ISR can be +called in the timer service routine. The Timer Server is designed to remain blocked until a task-based timer fires. This reduces the execution overhead @@ -512,7 +515,8 @@ preempted. @findex rtems_timer_initiate_server @example rtems_status_code rtems_timer_initiate_server( - unsigned32 stack_size, + rtems_unsigned32 priority, + rtems_unsigned32 stack_size, rtems_attribute attribute_set ) ); |