Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965119Ab2EPTiF (ORCPT ); Wed, 16 May 2012 15:38:05 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:44065 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932760Ab2EPTh6 convert rfc822-to-8bit (ORCPT ); Wed, 16 May 2012 15:37:58 -0400 MIME-Version: 1.0 In-Reply-To: <20120516193506.GM22985@linux.intel.com> References: <1337188023.3796.130.camel@schen9-DESK> <20120516193506.GM22985@linux.intel.com> Date: Wed, 16 May 2012 15:37:56 -0400 Message-ID: Subject: Re: SCSI RAM driver ported to 3.3 kernel for file system and I/O testing From: chetan loke To: Matthew Wilcox Cc: Tim Chen , linux-fsdevel , linux-scsi@vger.kernel.org, linux-kernel , Andi Kleen Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 914 Lines: 19 On Wed, May 16, 2012 at 3:35 PM, Matthew Wilcox wrote: > On Wed, May 16, 2012 at 03:31:55PM -0400, chetan loke wrote: >> > +               if (list_empty(&ram_device->commands)) >> > +                       wake_up_process(ram_device->thread); >> >> Didn't look in detail but if the queue is empty then why would you >> want to wake up the kthread? What if you just wake_up after >> list_add_tail below? > > If the list is non-empty, then the kthread has already been woken up > and doesn't need to be woken again. Sorry, not able to follow. wait_even_interruptible will put kthread to sleep. So how will it be already awake? -- 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/