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Re: some issues relating to current_thread
- From: Brij Bihari Pandey <fuzzhead012 at yahoo dot com>
- To: Nick Garnett <nickg at ecoscentric dot com>
- Cc: ecos-discuss at sources dot redhat dot com
- Date: Fri, 27 Sep 2002 00:37:46 -0700 (PDT)
- Subject: Re: [ECOS] some issues relating to current_thread
Hi Nick,
> To operate either of the priority inversion
> protocols correctly, the
> thread must access not only the mutex but also its
> own thread object
> and, if the priority is to be changed, the scheduler
> too. For priority
> inheritance the thread objects of other threads may
> also need to be
> accessed. So a thread has to take the scheduler lock
> anyway. The only
> situation where a thread could get away with only
> using a spinlock on
> the mutex is when the mutex implements no priority
> inversion protocol
> and there is no other thread contending for access.
What you have explained here, does that hold true in
case of semaphore, flag, mbox, mqueue also?
If you remember one of the issues that I had, in the
beginning of current thread was, schedlock mechanism
protecting (semaphore, flag, mbox, mqueue,mutex)
against each other also.
brij
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