[ath9k-devel] ath9k-rng: high cpu load

Hi Oleksij,

Please try the attached patch. No valid ADC randomness will cause the issue.

--
Regards,
Miaoqing


> Hallo all,
>
> on my last train trip i noticed that ath9k-rng produce continuous 15%
> cpu load. Probably two factor coused this issue:
> - my STA was not associated with any AP
> - on the road there is enough noise.
>
> from why i see, this code has all reasons to consume all CPU time it
> get, so far ath9k_rng_data_read can provide some data.
>
>         while (!kthread_should_stop()) {
>                 bytes_read = ath9k_rng_data_read(sc, rng_buf,
>                                                  ATH9K_RNG_BUF_SIZE);
>                 if (unlikely(!bytes_read)) {
>                         msleep_interruptible(10);
>                         continue;
>                 }
>
>                 /* sleep until entropy bits under write_wakeup_threshold
> */
>                 add_hwgenerator_randomness((void *)rng_buf, bytes_read,
>                                            ATH9K_RNG_ENTROPY(bytes_read));
>         }
>
> --
> Regards,
> Oleksij
>
>
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