From owner-freebsd-arch Sun Sep 8 19:20:15 2002 Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DF48637B40E; Sun, 8 Sep 2002 19:20:10 -0700 (PDT) Received: from rwcrmhc51.attbi.com (rwcrmhc51.attbi.com [204.127.198.38]) by mx1.FreeBSD.org (Postfix) with ESMTP id DDB9143E3B; Sun, 8 Sep 2002 19:20:09 -0700 (PDT) (envelope-from julian@elischer.org) Received: from InterJet.elischer.org ([12.232.206.8]) by rwcrmhc51.attbi.com (InterMail vM.4.01.03.27 201-229-121-127-20010626) with ESMTP id <20020909022008.PVRI19682.rwcrmhc51.attbi.com@InterJet.elischer.org>; Mon, 9 Sep 2002 02:20:08 +0000 Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id TAA54252; Sun, 8 Sep 2002 19:17:22 -0700 (PDT) Date: Sun, 8 Sep 2002 19:17:21 -0700 (PDT) From: Julian Elischer To: Jon Mini Cc: Jeff Roberson , arch@FreeBSD.ORG Subject: Re: UMA locks In-Reply-To: <20020909014206.GY7265@elvis.mu.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII 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 On Sun, 8 Sep 2002, Jon Mini wrote: > Julian Elischer [julian@elischer.org] wrote : > > > The UMA code is so central to all sorts of other modules that > > if you briefly need a lock to manipulate it's per-cpu structures, > > it is possible a spinlock might be a better choice. > > (depending on how long you hold it for.) > > Being able to uma_free while holding a spinlock would be very nice. of course we could always drop schedlock in thread_exit(), or do what we do do, which is call thread_stash() instead of thread_free() when we want to free the spare thread td_spare, but then we are doing EXTRA locking ops... hmm schedlock is being helppd for some quite long periods. It's probably worth looking at it some time.. > > -- > Jonathan Mini > http://www.freebsd.org/ > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message