nested task lock/unlock in rtems?

[Chris Johns]

Smith, Gene wrote:
> Joel Sherrill <joel at OARcorp.com> wrote, On 1/11/2005 11:22 AM:
> 
>> Smith, Gene wrote:
>>
>>> Can rtems keep track of nested calls to disable/enable preemption?
>>>
>>> E.g. within a task:
>>>
>>> lock
>>>    lock
>>>        lock
>>>        unlock
>>>    unlock
>>> unlock
>>>
>>> Where preemption is disabled on the first lock and not re-enabled 
>>> until the last unlock is called? And lock and unlock could be 
>>> accomplished by a call to rtems_task_mode. But is there anything in 
>>> rtems to ensure a balance?
>>
>>
>>
>> Do you mean via premption via the rtems_task_mode service?
> 
> 
> 
> Yes, as documented in the "RTEMS C User's Guide".
> 
>>
>> If so, then no.
> 

You are correct in saying RTEMS does not handle this but the application 
could by saving the "previous_mode_set" returned from the call to 
"rtems_task_mode" when disabling preemption and restoring it rather than 
enabling preemption to "unlock".

-- 
  Chris Johns