Kernel Newbies archive on lore.kernel.org
 help / color / Atom feed
From: William Tambe <tambewilliam@gmail.com>
To: Greg KH <greg@kroah.com>
Cc: kernelnewbies@kernelnewbies.org
Subject: Re: disabling timer interrupt until (system_state >= SYSTEM_RUNNING)
Date: Thu, 6 Feb 2020 19:53:56 -0500
Message-ID: <CAF8i9mPYrnUmyHfcn2cryaCV=h47GbH1Ec7bwv6A1vXv_VHDRA@mail.gmail.com> (raw)
In-Reply-To: <20200206182615.GA4092434@kroah.com>

On Thu, Feb 6, 2020 at 2:24 PM Greg KH <greg@kroah.com> wrote:
>
> On Thu, Feb 06, 2020 at 12:25:27PM -0500, William Tambe wrote:
> > Since voluntary preemption is used during kernel booting, is it safe
> > to disable timer interrupt until (system_state >= SYSTEM_RUNNING) ?
> >
> > Wouldn't it speed up booting ?
>
> Try it and see!
>
> :)
>
> Seriously, think about what needs to be done by the system during boot
> time.  Hardware is initialized, threads are spawned, lots of other
> things are going on.  It's not just one single process until that system
> state change happens by any means.

I am doing kernel porting work and I am able to see Linux booting all
the way to init without timer interrupt; despite kernel thread being
spawned during booting.

Perhaps I may start seeing issues if a module spawn a thread that
never voluntarily preempt itself ?

>
> thanks,
>
> greg k-h

_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

      reply index

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-06 17:25 William Tambe
2020-02-06 18:26 ` Greg KH
2020-02-07  0:53   ` William Tambe [this message]

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CAF8i9mPYrnUmyHfcn2cryaCV=h47GbH1Ec7bwv6A1vXv_VHDRA@mail.gmail.com' \
    --to=tambewilliam@gmail.com \
    --cc=greg@kroah.com \
    --cc=kernelnewbies@kernelnewbies.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Kernel Newbies archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/kernelnewbies/0 kernelnewbies/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 kernelnewbies kernelnewbies/ https://lore.kernel.org/kernelnewbies \
		kernelnewbies@kernelnewbies.org
	public-inbox-index kernelnewbies

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernelnewbies.kernelnewbies


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git