23 Feb
2022
23 Feb
'22
9:45 p.m.
Len Ovens <len(a)ovenwerks.net> writes:
In older kernels running:
pa ax |grep irq
will show a process for each irq in the form:
548 ? S 0:00 [irq/16-snd_ens1]
however, with kernel 5.15 most of these are gone except the one for
mei_me. This means that rtirq doesn't work and my device suffers from
more xruns than normal.
Has anyone else experienced this?
Are you running your kernel with the threadirqs option?
$ cat /proc/version
Linux version 5.15.0-18-lowlatency (buildd@lcy02-amd64-041) (gcc (Ubuntu 11.2.0-14ubuntu1)
11.2.0, GNU ld (GNU Binutils for Ubuntu) 2.37.50.20220106) #18-Ubuntu SMP PREEMPT Fri Jan
21 15:51:07 UTC 2022
$ cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-5.15.0-18-lowlatency root=UUID=XXX ro threadirqs quiet splash
threadirqs resume=UUID=XXX vt.handoff=1
$ ps ax|grep irq
12 ? S 0:18 [ksoftirqd/0]
21 ? S 0:13 [ksoftirqd/1]
27 ? S 0:15 [ksoftirqd/2]
33 ? S 0:22 [ksoftirqd/3]
39 ? S 0:22 [ksoftirqd/4]
45 ? S 0:12 [ksoftirqd/5]
51 ? S 0:16 [ksoftirqd/6]
57 ? S 0:15 [ksoftirqd/7]
120 ? S 0:00 [irq/9-acpi]
142 ? I< 0:00 [vfio-irqfd-clea]
143 ? S 0:00 [irq/16-ehci_hcd]
144 ? S 3:44 [irq/23-ehci_hcd]
145 ? S 2:33 [irq/12-i8042]
146 ? S 0:04 [irq/1-i8042]
147 ? S 0:00 [irq/8-rtc0]
230 ? S 0:00 [irq/18-i801_smb]
234 ? S 0:00 [irq/16-mmc0]
235 ? S 0:00 [irq/16-s-mmc0]
239 ? S 0:00 [irq/19-firewire]
242 ? S 0:04 [irq/25-ahci[000]
281 ? S 0:31 [irq/26-i915]
500 ? S 0:00 [irq/27-mei_me]
548 ? S 0:24 [irq/28-iwlwifi]
549 ? S 0:36 [irq/28-s-iwlwif]
598 ? S 0:00 [irq/29-snd_hda_]
1082 ? Ssl 0:01 /usr/sbin/irqbalance --foreground
1664 ? S 0:08 [irq/24-enp0s25]
18689 pts/1 S+ 0:00 grep --color=auto irq
--
David Kastrup