From 81c684d12ddc05bba4953e36e9cdd5939dde344b Mon Sep 17 00:00:00 2001 From: "Denis V. Lunev" Date: Tue, 8 Jul 2008 03:05:28 -0700 Subject: [PATCH] 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 --- net/ipv4/route.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 113cd2512ba7..79c1e74263a1 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; }