#include <asm/uaccess.h>
#include <asm/system.h>
-#include <asm/bitops.h>
+#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
struct gen_estimator
{
- struct gen_estimator *next;
+ struct list_head list;
struct gnet_stats_basic *bstats;
struct gnet_stats_rate_est *rate_est;
spinlock_t *stats_lock;
- unsigned interval;
int ewma_log;
u64 last_bytes;
u32 last_packets;
u32 avpps;
u32 avbps;
+ struct rcu_head e_rcu;
};
struct gen_estimator_head
{
struct timer_list timer;
- struct gen_estimator *list;
+ struct list_head list;
};
static struct gen_estimator_head elist[EST_MAX_INTERVAL+1];
-/* Estimator array lock */
+/* Protects against NULL dereference */
static DEFINE_RWLOCK(est_lock);
static void est_timer(unsigned long arg)
int idx = (int)arg;
struct gen_estimator *e;
- read_lock(&est_lock);
- for (e = elist[idx].list; e; e = e->next) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(e, &elist[idx].list, list) {
u64 nbytes;
u32 npackets;
u32 rate;
spin_lock(e->stats_lock);
+ read_lock(&est_lock);
+ if (e->bstats == NULL)
+ goto skip;
+
nbytes = e->bstats->bytes;
npackets = e->bstats->packets;
rate = (nbytes - e->last_bytes)<<(7 - idx);
e->last_packets = npackets;
e->avpps += ((long)rate - (long)e->avpps) >> e->ewma_log;
e->rate_est->pps = (e->avpps+0x1FF)>>10;
+skip:
+ read_unlock(&est_lock);
spin_unlock(e->stats_lock);
}
- mod_timer(&elist[idx].timer, jiffies + ((HZ<<idx)/4));
- read_unlock(&est_lock);
+ if (!list_empty(&elist[idx].list))
+ mod_timer(&elist[idx].timer, jiffies + ((HZ/4) << idx));
+ rcu_read_unlock();
}
/**
* &rate_est with the statistics lock grabed during this period.
*
* Returns 0 on success or a negative error code.
+ *
+ * NOTE: Called under rtnl_mutex
*/
int gen_new_estimator(struct gnet_stats_basic *bstats,
- struct gnet_stats_rate_est *rate_est, spinlock_t *stats_lock, struct rtattr *opt)
+ struct gnet_stats_rate_est *rate_est,
+ spinlock_t *stats_lock,
+ struct nlattr *opt)
{
struct gen_estimator *est;
- struct gnet_estimator *parm = RTA_DATA(opt);
+ struct gnet_estimator *parm = nla_data(opt);
+ int idx;
- if (RTA_PAYLOAD(opt) < sizeof(*parm))
+ if (nla_len(opt) < sizeof(*parm))
return -EINVAL;
if (parm->interval < -2 || parm->interval > 3)
if (est == NULL)
return -ENOBUFS;
- est->interval = parm->interval + 2;
+ idx = parm->interval + 2;
est->bstats = bstats;
est->rate_est = rate_est;
est->stats_lock = stats_lock;
est->last_packets = bstats->packets;
est->avpps = rate_est->pps<<10;
- est->next = elist[est->interval].list;
- if (est->next == NULL) {
- init_timer(&elist[est->interval].timer);
- elist[est->interval].timer.data = est->interval;
- elist[est->interval].timer.expires = jiffies + ((HZ<<est->interval)/4);
- elist[est->interval].timer.function = est_timer;
- add_timer(&elist[est->interval].timer);
+ if (!elist[idx].timer.function) {
+ INIT_LIST_HEAD(&elist[idx].list);
+ setup_timer(&elist[idx].timer, est_timer, idx);
}
- write_lock_bh(&est_lock);
- elist[est->interval].list = est;
- write_unlock_bh(&est_lock);
+
+ if (list_empty(&elist[idx].list))
+ mod_timer(&elist[idx].timer, jiffies + ((HZ/4) << idx));
+
+ list_add_rcu(&est->list, &elist[idx].list);
return 0;
}
+static void __gen_kill_estimator(struct rcu_head *head)
+{
+ struct gen_estimator *e = container_of(head,
+ struct gen_estimator, e_rcu);
+ kfree(e);
+}
+
/**
* gen_kill_estimator - remove a rate estimator
* @bstats: basic statistics
*
* Removes the rate estimator specified by &bstats and &rate_est
* and deletes the timer.
+ *
+ * NOTE: Called under rtnl_mutex
*/
void gen_kill_estimator(struct gnet_stats_basic *bstats,
struct gnet_stats_rate_est *rate_est)
{
int idx;
- struct gen_estimator *est, **pest;
+ struct gen_estimator *e, *n;
for (idx=0; idx <= EST_MAX_INTERVAL; idx++) {
- int killed = 0;
- pest = &elist[idx].list;
- while ((est=*pest) != NULL) {
- if (est->rate_est != rate_est || est->bstats != bstats) {
- pest = &est->next;
+
+ /* Skip non initialized indexes */
+ if (!elist[idx].timer.function)
+ continue;
+
+ list_for_each_entry_safe(e, n, &elist[idx].list, list) {
+ if (e->rate_est != rate_est || e->bstats != bstats)
continue;
- }
write_lock_bh(&est_lock);
- *pest = est->next;
+ e->bstats = NULL;
write_unlock_bh(&est_lock);
- kfree(est);
- killed++;
+ list_del_rcu(&e->list);
+ call_rcu(&e->e_rcu, __gen_kill_estimator);
}
- if (killed && elist[idx].list == NULL)
- del_timer(&elist[idx].timer);
}
}
/**
- * gen_replace_estimator - replace rate estimator configruation
+ * gen_replace_estimator - replace rate estimator configuration
* @bstats: basic statistics
* @rate_est: rate estimator statistics
* @stats_lock: statistics lock
*
* Returns 0 on success or a negative error code.
*/
-int
-gen_replace_estimator(struct gnet_stats_basic *bstats,
- struct gnet_stats_rate_est *rate_est, spinlock_t *stats_lock,
- struct rtattr *opt)
+int gen_replace_estimator(struct gnet_stats_basic *bstats,
+ struct gnet_stats_rate_est *rate_est,
+ spinlock_t *stats_lock, struct nlattr *opt)
{
- gen_kill_estimator(bstats, rate_est);
- return gen_new_estimator(bstats, rate_est, stats_lock, opt);
+ gen_kill_estimator(bstats, rate_est);
+ return gen_new_estimator(bstats, rate_est, stats_lock, opt);
}
projects / linux-2.6-omap-h63xx.git / blobdiff