From owner-freebsd-arch Fri Sep 28 4:55:55 2001 Delivered-To: freebsd-arch@freebsd.org Received: from elvis.mu.org (elvis.mu.org [216.33.66.196]) by hub.freebsd.org (Postfix) with ESMTP id 164D737B407 for ; Fri, 28 Sep 2001 04:55:53 -0700 (PDT) Received: by elvis.mu.org (Postfix, from userid 1192) id 29C7881D0C; Fri, 28 Sep 2001 06:55:53 -0500 (CDT) Date: Fri, 28 Sep 2001 06:55:53 -0500 From: Alfred Perlstein To: Daniel Eischen Cc: Julian Elischer , arch@FreeBSD.ORG Subject: Re: KSE next steps... Message-ID: <20010928065553.D59854@elvis.mu.org> References: <20010928040113.B59854@elvis.mu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from eischen@vigrid.com on Fri, Sep 28, 2001 at 07:53:39AM -0400 Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG * Daniel Eischen [010928 06:54] wrote: > On Fri, 28 Sep 2001, Alfred Perlstein wrote: > > * Julian Elischer [010928 02:44] wrote: > > > > > > int abort_thread(struct kt_context *ktc); /* if we find a thread in */ > > > /* this process that has this ktc, */ > > > /* then if it is sleeping, abort the syscall */ > > > /* if it is running, let it continue but set */ > > > /* flag so that if it tries to sleep, it aborts */ > > > /* instead */ > > > > Unless I'm misunderstanding you, this will not be possible without > > a tremendous amount of work, a variation that may work is allowing > > the syscall to run to completion, returning the error code and then > > aborting it. Too much code would have to change if tsleep became > > a cancellation point. > > Think of this as kill() on a process; it shouldn't be too different. > If PCATCH is specified in the tsleep, then it is terminated immediately, > otherwise it just remains pending until (and if) it is checked at a > later point in time. Regardless of whether PCATCH is specified, the > thread never returns to userland. The UTS is notified through an > upcall in the same way that it would be if a thread blocked (but with > a different completion status). This is quite different from winking out of existance when it tries to sleep. :) -- -Alfred Perlstein [alfred@freebsd.org] 'Instead of asking why a piece of software is using "1970s technology," start asking why software is ignoring 30 years of accumulated wisdom.' To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message