Re: can linux RT thread corrupt global variable?

I used locking for all the reads and writes to cpl when the problem initialy
surfaced. Interestingly the problem was the same after locking was used.
Like I said, the problem either occured during context switch, or during the
normal execution of a single thread.

----- Original Message -----
From: "Thorsten Holtkaemper" <[email protected]>
To: "Ming Lei" <[email protected]>
Sent: Tuesday, May 06, 2003 5:07 AM
Subject: Re: [pthreads-users] can linux RT thread corrupt global variable?


> On Tuesday 06 May 2003 02:39, Ming Lei wrote:
> > There is a global variable I define as 'int cpl'. All the threads and
main
> > process may alter cpl at any time. cpl may have one of these values {0,
> > 0xf000006e, 0xf0000068, 0xe0000000, 0xe0000060}.
>
> I'm not really sure if this is right, but if I understand correctly you
access
> this global variable without locking, assuming that the access to an
integer
> is an atomic operation. Depending on the platform and the implementation
this
> might not be true and lead to the experienced effect.
>
> But again - may be I'm plain wrong ...
>
> Regards,
> Thorsten
>
> P.S.: This mail was also sent to the NGPT mailing-list.