schedule()

[aksingh@hss.hns.com]

Hi,

  This is the way I intend to block the read call on my char device, if
there is no data to be read.

      void block() {
            DECLARE_WAITQUEUE(w, current);
            __add_wait_queue(&some_wait_queue, &w);
            current->state=TASK_INTERRUPTIBLE;
            if (!isready())
                  schedule();
            current->state=TASK_RUNNING;
            remove_wait_queue(&some_wait_queue, &w);
      }

Is this fine OR should I check after schedule() returns that there is now
something to read by calling isready() again. Isread() checks my input
queue to find, if there is something in the queue.

i.e should it be something like this :
      while (!isready())
            schedule();
      current->state=TASK_RUNNING;
      remove_wait_queue(&some_wait_queue, &w);

or, the previous one wld work just fine ?

thanks
Amit

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