From owner-cvs-all Sat Jan 20 23:31:55 2001 Delivered-To: cvs-all@freebsd.org Received: from moby.geekhouse.net (moby.geekhouse.net [64.81.6.36]) by hub.freebsd.org (Postfix) with ESMTP id D2B7237B402; Sat, 20 Jan 2001 23:31:33 -0800 (PST) Received: from laptop.baldwin.cx (john@dhcp150.geekhouse.net [192.168.1.150]) by moby.geekhouse.net (8.11.0/8.9.3) with ESMTP id f0L7Zrs76888; Sat, 20 Jan 2001 23:35:54 -0800 (PST) (envelope-from jhb@FreeBSD.org) Message-ID: X-Mailer: XFMail 1.4.0 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <200101210311.f0L3B3k73993@freefall.freebsd.org> Date: Sat, 20 Jan 2001 23:31:30 -0800 (PST) From: John Baldwin To: Jake Burkholder Subject: RE: cvs commit: src/sys/i386/include globals.h Cc: cvs-all@FreeBSD.org, cvs-committers@FreeBSD.org Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On 21-Jan-01 Jake Burkholder wrote: > jake 2001/01/20 19:11:03 PST > > Modified files: > sys/i386/include globals.h > Log: > Implement optimized PCPU accessors. These are necessary to support a > pre-emptable kernel. For variables of size 4 bytes or less they compile > to a single instruction, which does not allow a process to migrate cpus > in the middle, and get the value for the "wrong" cpu. Many per-cpu variables, esp. structs, will probably need to be protected via locks. curproc and other thread-related variables shouldn't be affected by preemption, however. -- John Baldwin -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.baldwin.cx/~john/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message