Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965423Ab2E0Bie (ORCPT ); Sat, 26 May 2012 21:38:34 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:36809 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755105Ab2E0BMk (ORCPT ); Sat, 26 May 2012 21:12:40 -0400 Message-Id: <20120527010435.457133244@linuxfoundation.org> User-Agent: quilt/0.60-19.1 Date: Sun, 27 May 2012 10:05:46 +0900 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Sujit Reddy Thumma , Nicolas Pitre , Chris Ball Subject: [ 83/94] mmc: sdio: avoid spurious calls to interrupt handlers In-Reply-To: <20120527010332.GA11170@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3023 Lines: 98 3.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicolas Pitre commit bbbc4c4d8c5face097d695f9bf3a39647ba6b7e7 upstream. Commit 06e8935feb ("optimized SDIO IRQ handling for single irq") introduced some spurious calls to SDIO function interrupt handlers, such as when the SDIO IRQ thread is started, or the safety check performed upon a system resume. Let's add a flag to perform the optimization only when a real interrupt is signaled by the host driver and we know there is no point confirming it. Reported-by: Sujit Reddy Thumma Signed-off-by: Nicolas Pitre Signed-off-by: Chris Ball Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/core/sdio.c | 2 +- drivers/mmc/core/sdio_irq.c | 11 +++++++---- include/linux/mmc/host.h | 2 ++ 3 files changed, 10 insertions(+), 5 deletions(-) --- a/drivers/mmc/core/sdio.c +++ b/drivers/mmc/core/sdio.c @@ -947,7 +947,7 @@ static int mmc_sdio_resume(struct mmc_ho } if (!err && host->sdio_irqs) - mmc_signal_sdio_irq(host); + wake_up_process(host->sdio_irq_thread); mmc_release_host(host); /* --- a/drivers/mmc/core/sdio_irq.c +++ b/drivers/mmc/core/sdio_irq.c @@ -28,18 +28,20 @@ #include "sdio_ops.h" -static int process_sdio_pending_irqs(struct mmc_card *card) +static int process_sdio_pending_irqs(struct mmc_host *host) { + struct mmc_card *card = host->card; int i, ret, count; unsigned char pending; struct sdio_func *func; /* * Optimization, if there is only 1 function interrupt registered - * call irq handler directly + * and we know an IRQ was signaled then call irq handler directly. + * Otherwise do the full probe. */ func = card->sdio_single_irq; - if (func) { + if (func && host->sdio_irq_pending) { func->irq_handler(func); return 1; } @@ -116,7 +118,8 @@ static int sdio_irq_thread(void *_host) ret = __mmc_claim_host(host, &host->sdio_irq_thread_abort); if (ret) break; - ret = process_sdio_pending_irqs(host->card); + ret = process_sdio_pending_irqs(host); + host->sdio_irq_pending = false; mmc_release_host(host); /* --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -323,6 +323,7 @@ struct mmc_host { unsigned int sdio_irqs; struct task_struct *sdio_irq_thread; + bool sdio_irq_pending; atomic_t sdio_irq_thread_abort; mmc_pm_flag_t pm_flags; /* requested pm features */ @@ -378,6 +379,7 @@ extern int mmc_cache_ctrl(struct mmc_hos static inline void mmc_signal_sdio_irq(struct mmc_host *host) { host->ops->enable_sdio_irq(host, 0); + host->sdio_irq_pending = true; wake_up_process(host->sdio_irq_thread); } -- 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/