Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261392AbVEXUp4 (ORCPT ); Tue, 24 May 2005 16:45:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262067AbVEXUp4 (ORCPT ); Tue, 24 May 2005 16:45:56 -0400 Received: from magic.adaptec.com ([216.52.22.17]:18612 "EHLO magic.adaptec.com") by vger.kernel.org with ESMTP id S261392AbVEXUpL convert rfc822-to-8bit (ORCPT ); Tue, 24 May 2005 16:45:11 -0400 X-MimeOLE: Produced By Microsoft Exchange V6.0.6487.1 content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: [PATCH 2.6.12-rc4-mm1 3/4] megaraid_sas: updating the driver Date: Tue, 24 May 2005 16:45:05 -0400 Message-ID: <60807403EABEB443939A5A7AA8A7458B01399B22@otce2k01.adaptec.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [PATCH 2.6.12-rc4-mm1 3/4] megaraid_sas: updating the driver Thread-Index: AcVaI7buUXFwsud3RM2sZH+FXr8cUAGeOYFw From: "Salyzyn, Mark" To: "James Bottomley" , "Arjan van de Ven" Cc: "Bagalkote, Sreenivas" , , , , "Andrew Morton" , "Christoph Hellwig" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1034 Lines: 26 James Bottomley writes: > On Mon, 2005-05-16 at 10:06 +0200, Arjan van de Ven wrote: >> > + spin_lock( instance->host_lock ); >> > + cmd->scmd->scsi_done( cmd->scmd ); >> > + spin_unlock( instance->host_lock ); >> >> are you really sure you don't want to use spin_lock_irqsave() here ? > >Actually, don't bother with the lock at all. scsi_done() is designed to >be called locklessly. Could I get an historical (2.4 & Distribution) perspective on this. At which point, or what code/include/manifest/version delineating it, would you say the driver is no longer, if ever, required to place a lock (host_lock or io_request_lock) around the scsi_done call? I expect (or hope) the answer to be: always needs io_request_lock in 2.4, never needed the host_lock in 2.5+. -- Mark Salyzyn - 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/