Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt

On Thu, 14 Jul 2005, Russell King wrote:
> 
> Umm.  Except, according to your description of what it's supposed to
> do, the above code can have an accumulating error.

No. It can have a local drift, but the point is, the error never gets 
worse - it _stays_ local.

There's no point in polling twice in immediate succession just because a 
sleep overslept. That's like a security guard testing each door twice for 
being locked, just because he overslept one round. Pointless.

But what matters is that you don't let your local errors accumulate into 
the big picture.

Now, if somebody wants to make nicer helper functions so that you can say

	timeout = ms_from_now(500);

or something instead of saying "timeout = jiffies + HZ/2", then hey, go 
wild. At that point it's just syntactic sugar, and maybe it's worth it.

		Linus
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

---

• Follow-Ups:
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Gerd Knorr <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Russell King <[email protected]>

• References:
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: dean gaudet <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Chris Wedgwood <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: dean gaudet <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Lee Revell <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Linus Torvalds <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Arjan van de Ven <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Vojtech Pavlik <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Linus Torvalds <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Arjan van de Ven <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Linus Torvalds <[email protected]>
  • Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
    • From: Russell King <[email protected]>

• Prev by Date: Re: eepro100/e100 broken in 2.6.13-rc3
• Next by Date: Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
• Previous by thread: Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
• Next by thread: Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
• Index(es):
  • Date
  • Thread

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]