Re: [Linux-ia64] Help with Ingo scheduler on IA64

Ingo Molnar
2002-01-21T22:41:03Z

On Mon, 21 Jan 2002, David Mosberger wrote:

> Ingo> Besides causing the current bug, it was superfluous in the old
> Ingo> scheduler as well, so i'm only wondering aloud - perhaps there
> Ingo> were more subtle reasons as well?
>
> No, it wasn't superfluous. It had to re-establish the original state
> after disabling interrupts to switch the TLB pinning.

since it went in pair with an irq-disable, it was indeed necessery.

i think i understand it now.

the end result: in the new scheduler it's guaranteed that switch_to() is
called with local interrupts disabled, and it's not allowed to reenable
them during switch_to().

Ingo