From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761164AbYEPPhN (ORCPT ); Fri, 16 May 2008 11:37:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754106AbYEPPgn (ORCPT ); Fri, 16 May 2008 11:36:43 -0400 Received: from dsl093-193-175.stl1.dsl.speakeasy.net ([66.93.193.175]:55636 "EHLO hades.sngx.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752480AbYEPPgl (ORCPT ); Fri, 16 May 2008 11:36:41 -0400 X-Greylist: delayed 1125 seconds by postgrey-1.27 at vger.kernel.org; Fri, 16 May 2008 11:36:41 EDT Message-ID: <482DA5B6.1020606@sngx.net> Date: Fri, 16 May 2008 10:18:14 -0500 From: James Cammarata User-Agent: Thunderbird 2.0.0.14 (X11/20080505) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: [PATCH updated] net: add ability to clear per-interface network statistics via procfs Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: James Cammarata Added the ability to write to /proc/net/dev in order to clear the interface counters for a given interface. The ability to zero out counters (especially the error counters) is extremely useful when troubleshooting interface issues. Now diffed against 2.6.25.4, and added some sanity checking. Syntax: echo 'net clear-stats ifdev' > /proc/net/dev Where "ifdev" is the device name you wish to clear. This code is based mainly on the code found in drivers/scsi/scsi_proc.c Signed-off-by: James Cammarata --- --- linux-2.6.25.4/net/core/dev.c 2008-05-15 10:00:12.000000000 -0500 +++ linux-2.6.25.4-jcammara/net/core/dev.c 2008-05-16 07:02:48.000000000 -0500 @@ -2455,2 +2455,78 @@ +/** + * proc_net_dev_write - handle writes to /proc/net/dev + * @file: not used + * @buf: buffer to write + * @length: length of buf, at most PAGE_SIZE + * @ppos: not used + * + * Description: this provides a mechanism to clear statistics on a + * per-interface basis + * "echo 'net clear-stats ifdev' >/proc/net/dev" + * with "ifdev" replaced by the device name you wish to clear. + * + */ +static ssize_t proc_net_dev_write(struct file *file, const char __user *buf, + size_t length, loff_t *ppos) +{ + char *buffer, *p; + char devname[IFNAMSIZ]; + struct net *net; + struct net_device *dev; + int err; + + if (!buf || length > PAGE_SIZE) + return -EINVAL; + + buffer = (char *)__get_free_page(GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + err = -EFAULT; + if (copy_from_user(buffer, buf, length)) + goto out; + + err = -EINVAL; + if (length < PAGE_SIZE) + buffer[length] = '\0'; + else if (buffer[PAGE_SIZE-1]) + goto out; + + err = -ENXIO; + net = get_proc_net(file->f_dentry->d_inode); + if (!net) + goto out; + + /* + * Usage: echo "net clear-stats ifdev" >/proc/net/dev + * with "ifdev" replaced by the device name you wish to clear. + */ + if (!strncmp("net clear-stats",buffer,15)) { + p = buffer + 16; + if(sscanf(p,"%16s",devname)>0) { + dev = dev_get_by_name(net,devname); + if (dev) { + if (dev->get_stats) { + struct net_device_stats *stats = + dev->get_stats(dev); + memset(stats,0, + sizeof(struct net_device_stats)); + } + dev_put(dev); + } + } + } + + /* + * convert success returns so that we return the + * number of bytes consumed. + */ + if (!err) + err = length; + + out: + free_page((unsigned long)buffer); + return err; +} + static void *softnet_seq_start(struct seq_file *seq, loff_t *pos) @@ -2498,2 +2574,3 @@ .read = seq_read, + .write = proc_net_dev_write, .llseek = seq_lseek,