net: use a deferred timer in rt_check_expire
For the sake of power saver lovers, use a deferrable timer to fire
rt_check_expire()
As some big routers cache equilibrium depends on garbage collection
done in time, we take into account elapsed time between two
rt_check_expire() invocations to adjust the amount of slots we have to
check.
Based on an initial idea and patch from Tero Kristo
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index a849bb1..cd76b3c 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -131,8 +131,8 @@
static int ip_rt_secret_interval __read_mostly = 10 * 60 * HZ;
static int rt_chain_length_max __read_mostly = 20;
-static void rt_worker_func(struct work_struct *work);
-static DECLARE_DELAYED_WORK(expires_work, rt_worker_func);
+static struct delayed_work expires_work;
+static unsigned long expires_ljiffies;
/*
* Interface to generic destination cache.
@@ -787,9 +787,12 @@
struct rtable *rth, *aux, **rthp;
unsigned long samples = 0;
unsigned long sum = 0, sum2 = 0;
+ unsigned long delta;
u64 mult;
- mult = ((u64)ip_rt_gc_interval) << rt_hash_log;
+ delta = jiffies - expires_ljiffies;
+ expires_ljiffies = jiffies;
+ mult = ((u64)delta) << rt_hash_log;
if (ip_rt_gc_timeout > 1)
do_div(mult, ip_rt_gc_timeout);
goal = (unsigned int)mult;
@@ -3397,6 +3400,8 @@
/* All the timers, started at system startup tend
to synchronize. Perturb it a bit.
*/
+ INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func);
+ expires_ljiffies = jiffies;
schedule_delayed_work(&expires_work,
net_random() % ip_rt_gc_interval + ip_rt_gc_interval);