Jan Hudec <bulb@ucw.cz> writes:
> On Thu, Jun 10, 2004 at 13:23:50 -0400, Ed L Cashin wrote:
>> Can anybody point out a specific problem with the (2.4) code below?
>> When I saw it, it made me uneasy because I'd heard somewhat vague
>> warnings against doing stuff like this. I can't see how the x86
>> implementation could have a problem, but maybe some other architecture
>> would?
>
> Sure I can -- I have looked at actual implementations when I was
> answering previous question....
>
>> static struct mylock {
>> spinlock_t lock;
>> unsigned long flags;
>> } mylock;
Thanks for that great explanation!
I should have seen immediately that by sharing the flags variable in
a static data structure, multiple CPUs would race.
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