From owner-freebsd-hackers Wed Jan 5 11:35:58 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from bingnet2.cc.binghamton.edu (bingnet2.cc.binghamton.edu [128.226.1.18]) by hub.freebsd.org (Postfix) with ESMTP id 9028315120 for ; Wed, 5 Jan 2000 11:35:56 -0800 (PST) (envelope-from zzhang@cs.binghamton.edu) Received: from sol.cs.binghamton.edu (cs1-gw.cs.binghamton.edu [128.226.171.72]) by bingnet2.cc.binghamton.edu (8.9.3/8.9.3) with SMTP id OAA17052 for ; Wed, 5 Jan 2000 14:35:51 -0500 (EST) Date: Wed, 5 Jan 2000 13:22:00 -0500 (EST) From: Zhihui Zhang To: freebsd-hackers@freebsd.org Subject: Post a signal within an interrupt handler Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG While reading the code vfs_aio.c, I find out some comments saying it is not safe to post a signal from the interrupt handler aio_physwakeup(). So it calls timeout(9) within that handler and let the timeout routine to post the signal. I do not understand this. Isn't the timeout mechanism also driven by an interrupt (clock)? Any enlightment is appreciated. -Zhihui To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message