ipvs: Embed estimator object into stats object
There's no reason for dynamically allocating an estimator object for every
stats object. Directly embed an estimator object into every stats object and
switch to using the kernel-provided list implementation. This makes the code
much simpler and faster, as we do not need to traverse the list of all
estimators to find the one belonging to a stats object. There's no need to use
an rwlock, as we only have one reader. Also reorder the members of the
estimator structure slightly to avoid padding overhead. This can't be done
with the stats object as the members are currently copied to our user space
object via memcpy() and changing it would break ABI.
Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Acked-by: Simon Horman <horms@verge.net.au>
diff --git a/net/ipv4/ipvs/ip_vs_est.c b/net/ipv4/ipvs/ip_vs_est.c
index 1d6e58e..5a20f93 100644
--- a/net/ipv4/ipvs/ip_vs_est.c
+++ b/net/ipv4/ipvs/ip_vs_est.c
@@ -17,6 +17,7 @@
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/sysctl.h>
+#include <linux/list.h>
#include <net/ip_vs.h>
@@ -44,28 +45,11 @@
*/
-struct ip_vs_estimator
-{
- struct ip_vs_estimator *next;
- struct ip_vs_stats *stats;
+static void estimation_timer(unsigned long arg);
- u32 last_conns;
- u32 last_inpkts;
- u32 last_outpkts;
- u64 last_inbytes;
- u64 last_outbytes;
-
- u32 cps;
- u32 inpps;
- u32 outpps;
- u32 inbps;
- u32 outbps;
-};
-
-
-static struct ip_vs_estimator *est_list = NULL;
-static DEFINE_RWLOCK(est_lock);
-static struct timer_list est_timer;
+static LIST_HEAD(est_list);
+static DEFINE_SPINLOCK(est_lock);
+static DEFINE_TIMER(est_timer, estimation_timer, 0, 0);
static void estimation_timer(unsigned long arg)
{
@@ -76,9 +60,9 @@
u64 n_inbytes, n_outbytes;
u32 rate;
- read_lock(&est_lock);
- for (e = est_list; e; e = e->next) {
- s = e->stats;
+ spin_lock(&est_lock);
+ list_for_each_entry(e, &est_list, list) {
+ s = container_of(e, struct ip_vs_stats, est);
spin_lock(&s->lock);
n_conns = s->conns;
@@ -114,19 +98,16 @@
s->outbps = (e->outbps+0xF)>>5;
spin_unlock(&s->lock);
}
- read_unlock(&est_lock);
+ spin_unlock(&est_lock);
mod_timer(&est_timer, jiffies + 2*HZ);
}
-int ip_vs_new_estimator(struct ip_vs_stats *stats)
+void ip_vs_new_estimator(struct ip_vs_stats *stats)
{
- struct ip_vs_estimator *est;
+ struct ip_vs_estimator *est = &stats->est;
- est = kzalloc(sizeof(*est), GFP_KERNEL);
- if (est == NULL)
- return -ENOMEM;
+ INIT_LIST_HEAD(&est->list);
- est->stats = stats;
est->last_conns = stats->conns;
est->cps = stats->cps<<10;
@@ -142,62 +123,40 @@
est->last_outbytes = stats->outbytes;
est->outbps = stats->outbps<<5;
- write_lock_bh(&est_lock);
- est->next = est_list;
- if (est->next == NULL) {
- setup_timer(&est_timer, estimation_timer, 0);
- est_timer.expires = jiffies + 2*HZ;
- add_timer(&est_timer);
- }
- est_list = est;
- write_unlock_bh(&est_lock);
- return 0;
+ spin_lock_bh(&est_lock);
+ if (list_empty(&est_list))
+ mod_timer(&est_timer, jiffies + 2 * HZ);
+ list_add(&est->list, &est_list);
+ spin_unlock_bh(&est_lock);
}
void ip_vs_kill_estimator(struct ip_vs_stats *stats)
{
- struct ip_vs_estimator *est, **pest;
- int killed = 0;
+ struct ip_vs_estimator *est = &stats->est;
- write_lock_bh(&est_lock);
- pest = &est_list;
- while ((est=*pest) != NULL) {
- if (est->stats != stats) {
- pest = &est->next;
- continue;
- }
- *pest = est->next;
- kfree(est);
- killed++;
- }
- while (killed && !est_list && try_to_del_timer_sync(&est_timer) < 0) {
- write_unlock_bh(&est_lock);
+ spin_lock_bh(&est_lock);
+ list_del(&est->list);
+ while (list_empty(&est_list) && try_to_del_timer_sync(&est_timer) < 0) {
+ spin_unlock_bh(&est_lock);
cpu_relax();
- write_lock_bh(&est_lock);
+ spin_lock_bh(&est_lock);
}
- write_unlock_bh(&est_lock);
+ spin_unlock_bh(&est_lock);
}
void ip_vs_zero_estimator(struct ip_vs_stats *stats)
{
- struct ip_vs_estimator *e;
+ struct ip_vs_estimator *est = &stats->est;
- write_lock_bh(&est_lock);
- for (e = est_list; e; e = e->next) {
- if (e->stats != stats)
- continue;
-
- /* set counters zero */
- e->last_conns = 0;
- e->last_inpkts = 0;
- e->last_outpkts = 0;
- e->last_inbytes = 0;
- e->last_outbytes = 0;
- e->cps = 0;
- e->inpps = 0;
- e->outpps = 0;
- e->inbps = 0;
- e->outbps = 0;
- }
- write_unlock_bh(&est_lock);
+ /* set counters zero, caller must hold the stats->lock lock */
+ est->last_inbytes = 0;
+ est->last_outbytes = 0;
+ est->last_conns = 0;
+ est->last_inpkts = 0;
+ est->last_outpkts = 0;
+ est->cps = 0;
+ est->inpps = 0;
+ est->outpps = 0;
+ est->inbps = 0;
+ est->outbps = 0;
}