On Tue, May 13, 2003 at 08:03:30PM +0200, Frank A. Uepping wrote:
> Hi,
> assume we have this:
>
> struct {
> spinlock_t lock;
> int flag;
> /* Some other stuff... */
> } v;
>
> v is accessed from different execution contexts including from ISR.
> While accessing v the lock will be held.
> However, do I have to qualify flag (and the other stuff) volatile
> to make sure that the users of v always see the most recent
> version of it?
> Or does spin_un/lock() imply *memory sync* (some form of
> barrier() or whatever)?
spin_lock is specified to have effect of mb().
AFAIK volatile is too waek on SMP anyway so you would need to use
mb() anyway...
-------------------------------------------------------------------------------
Jan 'Bulb' Hudec <bulb@ucw.cz>
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