From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936564AbXG0Nxx (ORCPT ); Fri, 27 Jul 2007 09:53:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933227AbXG0Nxp (ORCPT ); Fri, 27 Jul 2007 09:53:45 -0400 Received: from madara.hpl.hp.com ([192.6.19.124]:61925 "EHLO madara.hpl.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932768AbXG0Nxp (ORCPT ); Fri, 27 Jul 2007 09:53:45 -0400 Date: Fri, 27 Jul 2007 06:53:23 -0700 From: Stephane Eranian To: Ralf Baechle Cc: linux-kernel@vger.kernel.org, mucci@cs.utk.edu, linux-mips@linux-mips.org, ak@suse.de, akpm@linux-foundation.org Subject: Re: [PATCH] MIPS: add smp_call_function_single() Message-ID: <20070727135323.GF9828@frankl.hpl.hp.com> Reply-To: eranian@hpl.hp.com References: <20070727124451.GC9828@frankl.hpl.hp.com> <20070727125533.GD5118@linux-mips.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070727125533.GD5118@linux-mips.org> User-Agent: Mutt/1.4.1i Organisation: HP Labs Palo Alto Address: HP Labs, 1U-17, 1501 Page Mill road, Palo Alto, CA 94304, USA. E-mail: eranian@hpl.hp.com X-HPL-MailScanner: Found to be clean X-HPL-MailScanner-From: eranian@hpl.hp.com Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ralf, Here is take 2. [MIPS] add smp_call_function_single (take 2) signed-off-by: Stephane Eranian signed-off-by: Phil Mucci diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c index be7362b..d47234c 100644 --- a/arch/mips/kernel/smp.c +++ b/arch/mips/kernel/smp.c @@ -193,6 +193,53 @@ void smp_call_function_interrupt(void) } } +int smp_call_function_single(int cpu, void (*func) (void *info), void *info, int retry, + int wait) +{ + struct call_data_struct data; + int me = smp_processor_id(); + + /* + * Can die spectacularly if this CPU isn't yet marked online + */ + BUG_ON(!cpu_online(me)); + if (cpu == me) { + WARN_ON(1); + return -EBUSY; + } + + /* Can deadlock when called with interrupts disabled */ + WARN_ON(irqs_disabled()); + + data.func = func; + data.info = info; + atomic_set(&data.started, 0); + data.wait = wait; + if (wait) + atomic_set(&data.finished, 0); + + spin_lock(&smp_call_lock); + call_data = &data; + mb(); + + /* Send a message to the other CPU */ + core_send_ipi(cpu, SMP_CALL_FUNCTION); + + /* Wait for response */ + /* FIXME: lock-up detection, backtrace on lock-up */ + while (atomic_read(&data.started) != 1) + barrier(); + + if (wait) + while (atomic_read(&data.finished) != 1) + barrier(); + call_data = NULL; + spin_unlock(&smp_call_lock); + + return 0; +} +EXPORT_SYMBOL(smp_call_function_single); + static void stop_this_cpu(void *dummy) { /*