lkml.org 
[lkml]   [2022]   [Oct]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] hw_random: bcm2835: use hwrng_msleep() instead of cpu_relax()
From
On 10/10/22 08:06, 'Jason A. Donenfeld' via BCM-KERNEL-FEEDBACK-LIST,PDL 
wrote:
> Rather than busy looping, yield back to the scheduler and sleep for a
> bit in the event that there's no data. This should hopefully prevent the
> stalls that Mark reported:
>
> <6>[ 3.362859] Freeing initrd memory: 16196K
> <3>[ 23.160131] rcu: INFO: rcu_sched self-detected stall on CPU
> <3>[ 23.166057] rcu: 0-....: (2099 ticks this GP) idle=03b4/1/0x40000002 softirq=28/28 fqs=1050
> <4>[ 23.174895] (t=2101 jiffies g=-1147 q=2353 ncpus=4)
> <4>[ 23.180203] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1
> <4>[ 23.186125] Hardware name: BCM2835
> <4>[ 23.189837] PC is at bcm2835_rng_read+0x30/0x6c
> <4>[ 23.194709] LR is at hwrng_fillfn+0x71/0xf4
> <4>[ 23.199218] pc : [<c07ccdc8>] lr : [<c07cb841>] psr: 40000033
> <4>[ 23.205840] sp : f093df70 ip : 00000000 fp : 00000000
> <4>[ 23.211404] r10: c3c7e800 r9 : 00000000 r8 : c17e6b20
> <4>[ 23.216968] r7 : c17e6b64 r6 : c18b0a74 r5 : c07ccd99 r4 : c3f171c0
> <4>[ 23.223855] r3 : 000fffff r2 : 00000040 r1 : c3c7e800 r0 : c3f171c0
> <4>[ 23.230743] Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA Thumb Segment none
> <4>[ 23.238426] Control: 50c5387d Table: 0020406a DAC: 00000051
> <4>[ 23.244519] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1
>
> Link: https://lore.kernel.org/all/Y0QJLauamRnCDUef@sirena.org.uk/
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
--
Florian

\
 
 \ /
  Last update: 2022-10-11 00:06    [W:0.115 / U:0.540 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site