Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753299Ab3EHG5U (ORCPT ); Wed, 8 May 2013 02:57:20 -0400 Received: from cantor2.suse.de ([195.135.220.15]:42009 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752748Ab3EHG4t (ORCPT ); Wed, 8 May 2013 02:56:49 -0400 From: Takashi Iwai To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , Ming Lei Subject: [PATCH 1/3] firmware: Avoid superfluous usermodehelper lock Date: Wed, 8 May 2013 08:56:35 +0200 Message-Id: <1367996197-32748-2-git-send-email-tiwai@suse.de> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1367996197-32748-1-git-send-email-tiwai@suse.de> References: <1367996197-32748-1-git-send-email-tiwai@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2391 Lines: 84 When a firmware file can be loaded directly, there is no good reason to lock usermodehelper. It's needed only when the direct fw load fails and falls back to the user-mode helper. Signed-off-by: Takashi Iwai --- drivers/base/firmware_class.c | 42 +++++++++++++++++++++++------------------- 1 file changed, 23 insertions(+), 19 deletions(-) diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 4b1f926..9e1d39e 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -1006,7 +1006,7 @@ _request_firmware(const struct firmware **firmware_p, const char *name, struct device *device, bool uevent, bool nowait) { struct firmware *fw; - long timeout; + bool usermode_locked = false; int ret; if (!firmware_p) @@ -1017,31 +1017,35 @@ _request_firmware(const struct firmware **firmware_p, const char *name, goto out; ret = 0; - timeout = firmware_loading_timeout(); - if (nowait) { - timeout = usermodehelper_read_lock_wait(timeout); - if (!timeout) { - dev_dbg(device, "firmware: %s loading timed out\n", - name); - ret = -EBUSY; - goto out; - } - } else { - ret = usermodehelper_read_trylock(); - if (WARN_ON(ret)) { - dev_err(device, "firmware: %s will not be loaded\n", - name); - goto out; + if (!fw_get_filesystem_firmware(device, fw->priv)) { + long timeout = firmware_loading_timeout(); + if (nowait) { + timeout = usermodehelper_read_lock_wait(timeout); + if (!timeout) { + dev_dbg(device, "firmware: %s loading timed out\n", + name); + ret = -EBUSY; + goto out; + } + } else { + ret = usermodehelper_read_trylock(); + if (WARN_ON(ret)) { + dev_err(device, "firmware: %s will not be loaded\n", + name); + goto out; + } } - } - if (!fw_get_filesystem_firmware(device, fw->priv)) + usermode_locked = true; ret = fw_load_from_user_helper(fw, name, device, uevent, nowait, timeout); + } + if (!ret) ret = assign_firmware_buf(fw, device); - usermodehelper_read_unlock(); + if (usermode_locked) + usermodehelper_read_unlock(); out: if (ret < 0) { -- 1.8.2.1 -- 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/