From: Denis V. Lunev Date: Tue, 8 Jul 2008 10:05:28 +0000 (-0700) Subject: ipv4: remove flush_mutex from ipv4_sysctl_rtcache_flush X-Git-Tag: v2.6.27-rc1~969^2~196 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=81c684d12ddc05bba4953e36e9cdd5939dde344b;p=linux-2.6-omap-h63xx.git ipv4: remove flush_mutex from ipv4_sysctl_rtcache_flush It is possible to avoid locking at all in ipv4_sysctl_rtcache_flush by defining local ctl_table on the stack. The patch is based on the suggestion from Eric W. Biederman. Signed-off-by: Denis V. Lunev Signed-off-by: David S. Miller --- diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 113cd2512ba..79c1e74263a 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2873,22 +2873,20 @@ void ip_rt_multicast_event(struct in_device *in_dev) } #ifdef CONFIG_SYSCTL -static int ipv4_sysctl_rtcache_flush(ctl_table *ctl, int write, +static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) { if (write) { int flush_delay; + ctl_table ctl; struct net *net; - static DEFINE_MUTEX(flush_mutex); - mutex_lock(&flush_mutex); - ctl->data = &flush_delay; - proc_dointvec(ctl, write, filp, buffer, lenp, ppos); - ctl->data = NULL; - mutex_unlock(&flush_mutex); + memcpy(&ctl, __ctl, sizeof(ctl)); + ctl.data = &flush_delay; + proc_dointvec(&ctl, write, filp, buffer, lenp, ppos); - net = (struct net *)ctl->extra1; + net = (struct net *)__ctl->extra1; rt_cache_flush(net, flush_delay); return 0; }