Subject: Re: splx() optimization [was Re: SMP re-eetrancy in "bottom half"
To: None <jonathan@dsg.stanford.edu>
From: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
List: tech-kern
Date: 06/02/2005 11:19:56
hi,

> >i don't see any needs to have all interrupts ordered.
> 
> The issue I see is: how can we move interrupt handlers outside the
> biglock, whilst preserving existing spl() semantics, and yet stay
> deadlock-free?  Ordering of both interrupts and SPLs seems to be the
> way to go, at least for now.

what exactly do you mean by "making interrupts ordered"?

i have no objection if you just mean:
	given two arbitrary IPLs, IPL_A and IPL_B,
	either or both of the followings must be true.
		whenever IPL_A is blocked, IPL_B is also blocked.
		whenever IPL_B is blocked, IPL_A is also blocked.
(ie. how currently i386 port works.)

i have objection if you implies global IPLs.
(like your original proposal in 2003)

YAMAMOTO Takashi