From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754708Ab0E3Ota (ORCPT ); Sun, 30 May 2010 10:49:30 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:49502 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754522Ab0E3Ot3 (ORCPT ); Sun, 30 May 2010 10:49:29 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=sender:date:from:to:subject:message-id:mime-version:content-type :content-disposition:user-agent; b=lpQ4tqeLgCN30C2Zh+eQHX1WMbe71gJMRWbaCgHoIrxUATsbkFdEs1H8WEsB4I8Jlz qxE1Il/rLHzAnKYMGhzJAc7Hk/FjD7/iJtQZqn6bbk06S+ZIE35rsbSxH2noLlprgbRO mYrlsGyYyi5bbN0Dvo2C0TvSqXP64affkV0Ns= Date: Sun, 30 May 2010 16:52:40 +0200 From: Richard Zidlicky To: linux-kernel@vger.kernel.org Subject: schedule inside spin_lock_irqsave? Message-ID: <20100530145240.GA21559@linux-m68k.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, came across following snippet of code (2.6.34:drivers/media/dvb/siano/smscoreapi.c) and since prepare_to_wait is new for me I am wondering if this is can work? struct smscore_buffer_t *smscore_getbuffer(struct smscore_device_t *coredev) { struct smscore_buffer_t *cb = NULL; unsigned long flags; DEFINE_WAIT(wait); spin_lock_irqsave(&coredev->bufferslock, flags); /* This function must return a valid buffer, since the buffer list is * finite, we check that there is an available buffer, if not, we wait * until such buffer become available. */ prepare_to_wait(&coredev->buffer_mng_waitq, &wait, TASK_INTERRUPTIBLE); if (list_empty(&coredev->buffers)) schedule(); finish_wait(&coredev->buffer_mng_waitq, &wait); cb = (struct smscore_buffer_t *) coredev->buffers.next; list_del(&cb->entry); spin_unlock_irqrestore(&coredev->bufferslock, flags); return cb; } Regards Richard