From patchwork Mon May 11 16:41:31 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tejun Heo X-Patchwork-Id: 470964 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3252A140157 for ; Tue, 12 May 2015 02:43:23 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b=dVb4iXKd; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752832AbbEKQlv (ORCPT ); Mon, 11 May 2015 12:41:51 -0400 Received: from mail-qg0-f43.google.com ([209.85.192.43]:33514 "EHLO mail-qg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752543AbbEKQlo (ORCPT ); Mon, 11 May 2015 12:41:44 -0400 Received: by qgdy78 with SMTP id y78so70746356qgd.0; Mon, 11 May 2015 09:41:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=a230RQtkcSF23L4Ly0sxexLcpVUn6uJS0DBYH7Wai7k=; b=dVb4iXKdih7n4Vk/VEHG/q/M1ID9YJWDAz6IGhL+p0e2oq3IM/jKfPANVWsRha9aWt H8Dz2C0C1O3z6de3GYWCz7hkmKGj4/pwbIcXFANy9QsPqP6OGEDcgseW2HmIvt+jtXOM GPxuIDvh4QSmzoNr78M8HTLOxWZ0qRsj6LcVSIBAAZY7EWijQ+JPaeGYGf5Ofx1MJbiY TU9JfNRSFdqDt7f9ALGPkm7JZ4uv15w18p5QYfwhk5gXW7EhFYVYtYtL0ewToyLD2EHf 3XeOgejuExPUodazkx60mU9AkqlEjhQlgiYiJxHVgpbbUz+C7fkVz94vGjN3CvoJD5Q/ tGYA== X-Received: by 10.55.21.218 with SMTP id 87mr24308954qkv.94.1431362504035; Mon, 11 May 2015 09:41:44 -0700 (PDT) Received: from htj.duckdns.org.lan (207-38-238-8.c3-0.wsd-ubr1.qens-wsd.ny.cable.rcn.com. [207.38.238.8]) by mx.google.com with ESMTPSA id i14sm10921775qkh.5.2015.05.11.09.41.42 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 11 May 2015 09:41:43 -0700 (PDT) From: Tejun Heo To: davem@davemloft.net Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, penguin-kernel@I-love.SAKURA.ne.jp, sd@queasysnail.net, Tejun Heo Subject: [PATCH 1/4] netconsole: remove unnecessary netconsole_target_get/out() from write_msg() Date: Mon, 11 May 2015 12:41:31 -0400 Message-Id: <1431362494-9874-2-git-send-email-tj@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1431362494-9874-1-git-send-email-tj@kernel.org> References: <1431362494-9874-1-git-send-email-tj@kernel.org> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org write_msg() grabs target_list_lock and walks target_list invoking netpool_send_udp() on each target. Curiously, it protects each iteration with netconsole_target_get/put() even though it never releases target_list_lock which protects all the members. While this doesn't harm anything, it doesn't serve any purpose either. The items on the list can't go away while target_list_lock is held. Remove the unnecessary get/put pair. Signed-off-by: Tejun Heo Cc: David Miller --- drivers/net/netconsole.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c index 15731d1..30c0524 100644 --- a/drivers/net/netconsole.c +++ b/drivers/net/netconsole.c @@ -744,7 +744,6 @@ static void write_msg(struct console *con, const char *msg, unsigned int len) spin_lock_irqsave(&target_list_lock, flags); list_for_each_entry(nt, &target_list, list) { - netconsole_target_get(nt); if (nt->enabled && netif_running(nt->np.dev)) { /* * We nest this inside the for-each-target loop above @@ -760,7 +759,6 @@ static void write_msg(struct console *con, const char *msg, unsigned int len) left -= frag; } } - netconsole_target_put(nt); } spin_unlock_irqrestore(&target_list_lock, flags); }