From owner-p4-projects Wed Apr 10 8:26:23 2002 Delivered-To: p4-projects@freebsd.org Received: by hub.freebsd.org (Postfix, from userid 32767) id D3D1137B405; Wed, 10 Apr 2002 08:26:15 -0700 (PDT) Delivered-To: perforce@freebsd.org Received: from anchor-post-36.mail.demon.net (anchor-post-36.mail.demon.net [194.217.242.94]) by hub.freebsd.org (Postfix) with ESMTP id 57C0337B400; Wed, 10 Apr 2002 08:26:14 -0700 (PDT) Received: from mailgate.nlsystems.com ([62.49.251.130] helo=herring.nlsystems.com) by anchor-post-36.mail.demon.net with esmtp (Exim 3.35 #1) id 16vJzB-000MpN-0a; Wed, 10 Apr 2002 16:26:13 +0100 Received: from herring (herring [10.0.0.2]) by herring.nlsystems.com (8.12.2/8.11.2) with ESMTP id g3AFQC3I014120; Wed, 10 Apr 2002 16:26:12 +0100 (BST) (envelope-from dfr@nlsystems.com) Date: Wed, 10 Apr 2002 16:26:12 +0100 (BST) From: Doug Rabson To: Jake Burkholder Cc: John Baldwin , Peter Wemm , Perforce Change Reviews Subject: Re: PERFORCE change 9504 for review In-Reply-To: <20020410110650.C209@locore.ca> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-p4-projects@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Wed, 10 Apr 2002, Jake Burkholder wrote: > Apparently, On Wed, Apr 10, 2002 at 09:06:18AM -0400, > John Baldwin said words to the effect of; > > > > > On 10-Apr-2002 Peter Wemm wrote: > > > http://people.freebsd.org/~peter/p4db/chv.cgi?CH=9504 > > > > > > Change 9504 by peter@peter_thunder on 2002/04/10 04:51:36 > > > > > > Use dfr's fix instead of my hack. I expect he'll commit this to > > > freefall soon. :-) > > > > Yep, much better. :) > > Well, now the flag checking code is duplicated in both the trap and syscall > return paths, alpha is the same. One wonders if the FRAME_SYSCALL optimization > is actually worth all this complication. I think its still worth it - it still does a lot less work in the common case. Bear in mind that calling ast() is quite rare and being forced to do a full exception restore (e.g. for a signal) is even rarer. A harmless extra call to ast() in that case is unlikely to be noticable. Having said that, for ia64 at least, it should be possible for the syscall to bypass the ast() bits at the beginning of exception_restore(). As long as syscall sets (p1,p2) to (1,0), it can jump to label 2 in exception_restore. -- Doug Rabson Mail: dfr@nlsystems.com Phone: +44 20 8348 6160 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe p4-projects" in the body of the message