Re: [PATCH] "volatile considered harmful", take 2

[Bernd Eckenfels]

In article <6143.1178828419@xxxxxxx> you wrote:
> +Consider a typical block of kernel code:
> +
> +    spin_lock(&the_lock);
> +    do_something_on(&shared_data);
> +    do_something_else_with(&shared_data);
> +    spin_unlock(&the_lock);
> +
> +If all the code follows the locking rules, the value of shared_data cannot
> +change unexpectedly while the_lock is held.

Well maybe it is trivial, but I would add e.g. "all places where the
shared_data is accessed must be protected by this spinlock"

> +  - The jiffies variable is special in that it can have a different value

what about other atomic readable counters (like interface counters)?

Gruss
Bernd
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