Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262920AbVDHSiW (ORCPT ); Fri, 8 Apr 2005 14:38:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262918AbVDHSiW (ORCPT ); Fri, 8 Apr 2005 14:38:22 -0400 Received: from fmr15.intel.com ([192.55.52.69]:11215 "EHLO fmsfmr005.fm.intel.com") by vger.kernel.org with ESMTP id S262916AbVDHSiS convert rfc822-to-8bit (ORCPT ); Fri, 8 Apr 2005 14:38:18 -0400 X-MimeOLE: Produced By Microsoft Exchange V6.5.7226.0 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Subject: RE: [patch] sched: unlocked context-switches Date: Fri, 8 Apr 2005 11:38:09 -0700 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [patch] sched: unlocked context-switches Thread-Index: AcU8NMnGT13uUbhkS7C6cAuU9VdN9gANDPHw From: "Luck, Tony" To: "Ingo Molnar" , Cc: "Andrew Morton" , , X-OriginalArrivalTime: 08 Apr 2005 18:38:07.0332 (UTC) FILETIME=[1B5EBA40:01C53C6A] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1035 Lines: 22 >tested on x86, and all other arches should work as well, but if an >architecture has irqs-off assumptions in its switch_to() logic >it might break. (I havent found any but there may such assumptions.) The ia64_switch_to() code includes a section that can change a pinned MMU mapping (when the stack for the new process is in a different granule from the stack for the old process). The code beyond the ".map" label in arch/ia64/kernel/entry.S includes the comment: .map: rsm psr.ic // interrupts (psr.i) are already disabled here I don't think that it would be sufficient to merely add psr.i to this rsm (and to the ssm 15 lines above). That would leave a window where we could take an interrupt, but not be sure that the current stack is pinned. -Tony - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/