lkml.org 
[lkml]   [2017]   [Jun]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC][PATCHv3 2/5] printk: introduce printing kernel thread
On Fri, 30 Jun 2017 21:42:24 +0900
Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> wrote:

> I apply a very simple litmus test. if the answer to the question
> "so we leave console_unlock() and there are pending messages,
> who and when is going to flush the remaining messages?" is
> "something sometime in the future" then it's a no-no.

I totally agree with this, but...

>
> "something sometime in the future" is equal to "no one".
>
> we must stay and continue printing. because it gives the right
> answer - "current process and right now. until someone else
> (+printk_kthread) takes over".

Would it be acceptable to have a user knob that allows for it not to
happen? That is, let the user of the kernel decide if they care about
critical prints or not? If a knob says, "only print X, then offload"
would that be allowed. Of course the default would be "only print ALL
OF IT" to keep the current behavior.

A lot of times the console isn't recorded to debug hard lock ups. I
know most desktops running a GUI do not. When ever my workstation locks
up, and it has no serial, I don't get to see the dmesg at all. In this
situation, I don't care if the prints are offloaded or not.

-- Steve

\
 
 \ /
  Last update: 2017-06-30 23:13    [W:2.118 / U:0.104 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site