Re: Query on lock protection in random number driver

[Andi Kleen]

Nikanth Karthikesan <knikanth@xxxxxxx> writes:
>
> Also the globals random_read_wakeup_thresh and
> random_write_wakeup_thresh are not at all protected by any locks! Why
> locks are not needed for these?

Reading variables sizeof <= native word size (32bit or 64bit depending
on architecture) is atomic by itself. This is not necessarily
guaranteed in ISO-C or POSIX threads, but Linux can assume that.

-Andi
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