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From: Oleksij Rempel <linux@rempel-privat.de>
To: ath9k-devel@lists.ath9k.org
Subject: [ath9k-devel] ath9k-rng: high cpu load
Date: Fri, 4 Mar 2016 16:21:02 +0100	[thread overview]
Message-ID: <56D9A7DE.5030209@rempel-privat.de> (raw)

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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             reply	other threads:[~2016-03-04 15:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-04 15:21 Oleksij Rempel [this message]
2016-03-11  9:46 ` [ath9k-devel] ath9k-rng: high cpu load miaoqing at codeaurora.org
2016-03-14 14:47   ` Oleksij Rempel
2016-03-14 15:14     ` Oleksij Rempel

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