* 5.18 missing /proc/sys/kernel/sched_autogroup_enabled?
@ 2022-05-29 23:52 Ivan Kozik
2022-05-30 7:45 ` Peter Zijlstra
0 siblings, 1 reply; 4+ messages in thread
From: Ivan Kozik @ 2022-05-29 23:52 UTC (permalink / raw)
To: linux-kernel; +Cc: nizhen, peterz, mingo
Hello,
I noticed that /proc/sys/kernel/sched_autogroup_enabled seems to have
gone missing in 5.18. Am I doing something wrong, or is this a
regression?
I also noticed that booting 5.18 with "noautogroup" results in a
"kernel: failed when register_sysctl sched_autogroup_sysctls to
kernel" message. Because of the error and the missing
/proc/sys/kernel/sched_autogroup_enabled, it is unclear whether
autogroup is enabled or not.
Please see below for my testing. These kernels came from
https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.18/ but I saw the
same thing with a 5.18.0 on NixOS.
Best regards,
Ivan
5.17, default:
at@ubuntu2204:~$ uname -a
Linux ubuntu2204 5.17.11-051711-generic #202205251331 SMP PREEMPT Wed
May 25 13:57:33 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
at@ubuntu2204:~$ journalctl -b | grep -i autogroup
at@ubuntu2204:~$ cat /proc/sys/kernel/sched_autogroup_enabled
1
5.17, noautogroup:
at@ubuntu2204:~$ uname -a
Linux ubuntu2204 5.17.11-051711-generic #202205251331 SMP PREEMPT Wed
May 25 13:57:33 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
at@ubuntu2204:~$ journalctl -b | grep -i autogroup
May 29 15:58:17 ubuntu2204 kernel: Command line:
BOOT_IMAGE=/boot/vmlinuz-5.17.11-051711-generic
root=UUID=20672a55-02fc-49b3-8c04-bd040f068096 ro
find_preseed=/preseed.cfg auto noprompt priority=critical locale=en_US
quiet splash noautogroup
May 29 15:58:17 ubuntu2204 kernel: Kernel command line:
BOOT_IMAGE=/boot/vmlinuz-5.17.11-051711-generic
root=UUID=20672a55-02fc-49b3-8c04-bd040f068096 ro
find_preseed=/preseed.cfg auto noprompt priority=critical locale=en_US
quiet splash noautogroup
at@ubuntu2204:~$ cat /proc/sys/kernel/sched_autogroup_enabled
0
5.18, default:
at@ubuntu2204:~$ uname -a
Linux ubuntu2204 5.18.0-051800-generic #202205222030 SMP
PREEMPT_DYNAMIC Sun May 22 20:33:46 UTC 2022 x86_64 x86_64 x86_64
GNU/Linux
at@ubuntu2204:~$ journalctl -b | grep -i autogroup
at@ubuntu2204:~$ cat /proc/sys/kernel/sched_autogroup_enabled
cat: /proc/sys/kernel/sched_autogroup_enabled: No such file or directory
root@ubuntu2204:~# sysctl -a | grep -i autogroup
5.18, noautogroup:
at@ubuntu2204:~$ uname -a
Linux ubuntu2204 5.18.0-051800-generic #202205222030 SMP
PREEMPT_DYNAMIC Sun May 22 20:33:46 UTC 2022 x86_64 x86_64 x86_64
GNU/Linux
at@ubuntu2204:~$ journalctl -b | grep -i autogroup
May 29 15:53:17 ubuntu2204 kernel: Command line:
BOOT_IMAGE=/boot/vmlinuz-5.18.0-051800-generic
root=UUID=20672a55-02fc-49b3-8c04-bd040f068096 ro
find_preseed=/preseed.cfg auto noprompt priority=critical locale=en_US
quiet splash noautogroup
May 29 15:53:17 ubuntu2204 kernel: Kernel command line:
BOOT_IMAGE=/boot/vmlinuz-5.18.0-051800-generic
root=UUID=20672a55-02fc-49b3-8c04-bd040f068096 ro
find_preseed=/preseed.cfg auto noprompt priority=critical locale=en_US
quiet splash noautogroup
May 29 15:53:17 ubuntu2204 kernel: failed when register_sysctl
sched_autogroup_sysctls to kernel
at@ubuntu2204:~$ cat /proc/sys/kernel/sched_autogroup_enabled
cat: /proc/sys/kernel/sched_autogroup_enabled: No such file or directory
root@ubuntu2204:~# cat /boot/config-5.1[78]* | grep -i config_sysctl=
CONFIG_SYSCTL=y
CONFIG_SYSCTL=y
root@ubuntu2204:~# cat /boot/config-5.1[78]* | grep -i autogroup
CONFIG_SCHED_AUTOGROUP=y
CONFIG_SCHED_AUTOGROUP=y
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: 5.18 missing /proc/sys/kernel/sched_autogroup_enabled?
2022-05-29 23:52 5.18 missing /proc/sys/kernel/sched_autogroup_enabled? Ivan Kozik
@ 2022-05-30 7:45 ` Peter Zijlstra
2022-05-30 9:48 ` Ivan Kozik
2022-05-30 10:45 ` [tip: sched/urgent] sched/autogroup: Fix sysctl move tip-bot2 for Peter Zijlstra
0 siblings, 2 replies; 4+ messages in thread
From: Peter Zijlstra @ 2022-05-30 7:45 UTC (permalink / raw)
To: Ivan Kozik; +Cc: linux-kernel, nizhen, mingo
On Sun, May 29, 2022 at 11:52:42PM +0000, Ivan Kozik wrote:
> Hello,
>
> I noticed that /proc/sys/kernel/sched_autogroup_enabled seems to have
> gone missing in 5.18. Am I doing something wrong, or is this a
> regression?
>
> I also noticed that booting 5.18 with "noautogroup" results in a
> "kernel: failed when register_sysctl sched_autogroup_sysctls to
> kernel" message. Because of the error and the missing
> /proc/sys/kernel/sched_autogroup_enabled, it is unclear whether
> autogroup is enabled or not.
*sigh*, I think this is yet another one of the sysctl move patches gone
bad :/ Specifically:
c8eaf6ac76f4 ("sched: move autogroup sysctls into its own file")
Does something like the below help?
---
diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c
index 16092b49ff6a..4ebaf97f7bd8 100644
--- a/kernel/sched/autogroup.c
+++ b/kernel/sched/autogroup.c
@@ -36,6 +36,7 @@ void __init autogroup_init(struct task_struct *init_task)
kref_init(&autogroup_default.kref);
init_rwsem(&autogroup_default.lock);
init_task->signal->autogroup = &autogroup_default;
+ sched_autogroup_sysctl_init();
}
void autogroup_free(struct task_group *tg)
@@ -219,7 +220,6 @@ void sched_autogroup_exit(struct signal_struct *sig)
static int __init setup_autogroup(char *str)
{
sysctl_sched_autogroup_enabled = 0;
- sched_autogroup_sysctl_init();
return 1;
}
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: 5.18 missing /proc/sys/kernel/sched_autogroup_enabled?
2022-05-30 7:45 ` Peter Zijlstra
@ 2022-05-30 9:48 ` Ivan Kozik
2022-05-30 10:45 ` [tip: sched/urgent] sched/autogroup: Fix sysctl move tip-bot2 for Peter Zijlstra
1 sibling, 0 replies; 4+ messages in thread
From: Ivan Kozik @ 2022-05-30 9:48 UTC (permalink / raw)
To: Peter Zijlstra; +Cc: linux-kernel, nizhen, mingo
On Mon, May 30, 2022 at 7:45 AM Peter Zijlstra <peterz@infradead.org> wrote:
> *sigh*, I think this is yet another one of the sysctl move patches gone
> bad :/ Specifically:
>
> c8eaf6ac76f4 ("sched: move autogroup sysctls into its own file")
>
> Does something like the below help?
Hi Peter,
Yes, your patch does fix both the missing
/proc/sys/kernel/sched_autogroup_enabled and the error when using
noautogroup.
Thank you,
Ivan
^ permalink raw reply [flat|nested] 4+ messages in thread* [tip: sched/urgent] sched/autogroup: Fix sysctl move
2022-05-30 7:45 ` Peter Zijlstra
2022-05-30 9:48 ` Ivan Kozik
@ 2022-05-30 10:45 ` tip-bot2 for Peter Zijlstra
1 sibling, 0 replies; 4+ messages in thread
From: tip-bot2 for Peter Zijlstra @ 2022-05-30 10:45 UTC (permalink / raw)
To: linux-tip-commits; +Cc: Ivan Kozik, Peter Zijlstra (Intel), x86, linux-kernel
The following commit has been merged into the sched/urgent branch of tip:
Commit-ID: 82f586f923e3ac6062bc7867717a7f8afc09e0ff
Gitweb: https://git.kernel.org/tip/82f586f923e3ac6062bc7867717a7f8afc09e0ff
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Mon, 30 May 2022 09:45:38 +02:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Mon, 30 May 2022 12:36:36 +02:00
sched/autogroup: Fix sysctl move
Ivan reported /proc/sys/kernel/sched_autogroup_enabled went walk-about
and using the noautogroup command line parameter would result in a
boot error message.
Turns out the sysctl move placed the init function wrong.
Fixes: c8eaf6ac76f4 ("sched: move autogroup sysctls into its own file")
Reported-by: Ivan Kozik <ivan@ludios.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Ivan Kozik <ivan@ludios.org>
Link: https://lkml.kernel.org/r/YpR2IqndgsyMzN00@worktop.programming.kicks-ass.net
---
kernel/sched/autogroup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c
index 16092b4..4ebaf97 100644
--- a/kernel/sched/autogroup.c
+++ b/kernel/sched/autogroup.c
@@ -36,6 +36,7 @@ void __init autogroup_init(struct task_struct *init_task)
kref_init(&autogroup_default.kref);
init_rwsem(&autogroup_default.lock);
init_task->signal->autogroup = &autogroup_default;
+ sched_autogroup_sysctl_init();
}
void autogroup_free(struct task_group *tg)
@@ -219,7 +220,6 @@ void sched_autogroup_exit(struct signal_struct *sig)
static int __init setup_autogroup(char *str)
{
sysctl_sched_autogroup_enabled = 0;
- sched_autogroup_sysctl_init();
return 1;
}
^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2022-05-30 10:46 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-05-29 23:52 5.18 missing /proc/sys/kernel/sched_autogroup_enabled? Ivan Kozik
2022-05-30 7:45 ` Peter Zijlstra
2022-05-30 9:48 ` Ivan Kozik
2022-05-30 10:45 ` [tip: sched/urgent] sched/autogroup: Fix sysctl move tip-bot2 for Peter Zijlstra
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.