From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleksij Rempel Date: Mon, 14 Mar 2016 15:47:47 +0100 Subject: [ath9k-devel] ath9k-rng: high cpu load In-Reply-To: References: <56D9A7DE.5030209@rempel-privat.de> Message-ID: <56E6CF13.8020105@rempel-privat.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ath9k-devel@lists.ath9k.org Hi, compilation is filed with: CC [M] drivers/net/wireless/ath/wcn36xx/smd.o /home/oleksij/tmp/linux/drivers/net/wireless/ath/ath9k/rng.c: In function ?ath9k_rng_delay_get?: /home/oleksij/tmp/linux/drivers/net/wireless/ath/ath9k/rng.c:61:3: error: ?delay? undeclared (first use in this function) delay = 10; ^ /home/oleksij/tmp/linux/drivers/net/wireless/ath/ath9k/rng.c:61:3: note: each undeclared identifier is reported only once for each function it appears in /home/oleksij/tmp/linux/drivers/net/wireless/ath/ath9k/rng.c:68:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ /home/oleksij/tmp/linux/scripts/Makefile.build:258: recipe for target 'drivers/net/wireless/ath/ath9k/rng.o' failed Am 11.03.2016 um 10:38 schrieb miaoqing at codeaurora.org: > 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 >> >> -- Regards, Oleksij -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 213 bytes Desc: OpenPGP digital signature Url : http://lists.ath9k.org/pipermail/ath9k-devel/attachments/20160314/db4dc053/attachment.pgp