06.08.2013 Views

pSOSystem System Calls - Read

pSOSystem System Calls - Read

pSOSystem System Calls - Read

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

pSOS+ <strong>System</strong> <strong>Calls</strong> t_suspend<br />

See Also<br />

3. t_resume() is the only call that reverses a suspension.<br />

4. A task can be suspended in addition to being blocked. For example, if a task is<br />

waiting for a message at a queue when suspension is ordered, suspension<br />

continues after a message has been received. For another example, consider a<br />

task P that is blocked while it waits for an event. Another task Q decides that P<br />

must not run, and therefore Q suspends P. When P receives the event, it must<br />

still wait for a resumption before it can be ready to run. On the other hand, if Q<br />

resumes P while P is still waiting for its event, P continues to wait for the event.<br />

Multiprocessor Considerations<br />

If tid identifies a global task residing on another processor node, the local kernel<br />

internally makes an RSC to the remote node to suspend the task.<br />

Callable From<br />

■ Task<br />

t_resume<br />

<strong>pSO<strong>System</strong></strong> <strong>System</strong> <strong>Calls</strong> 1-163<br />

1

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!