This patch holds frag heads in lru queue for the evictor.
Please consider for inclusion.
Regards,
Patrick
diff -urN ../ppp_filter/linux/linux-2.4.20-clean/net/ipv4/ip_fragment.c linux-2.4.20/net/ipv4/ip_fragment.c
--- ../ppp_filter/linux/linux-2.4.20-clean/net/ipv4/ip_fragment.c 2002-02-25 20:38:14.000000000 +0100
+++ linux-2.4.20/net/ipv4/ip_fragment.c 2003-02-16 05:28:17.000000000 +0100
@@ -19,6 +19,7 @@
* Bill Hawes : Frag accounting and evictor fixes.
* John McDonald : 0 length frag bug.
* Alexey Kuznetsov: SMP races, threading, cleanup.
+ * Patrick McHardy : LRU queue of frag heads for evictor.
*/
#include <linux/config.h>
@@ -26,6 +27,7 @@
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/skbuff.h>
+#include <linux/list.h>
#include <linux/ip.h>
#include <linux/icmp.h>
#include <linux/netdevice.h>
@@ -67,6 +69,7 @@
/* Describe an entry in the "incomplete datagrams" queue. */
struct ipq {
struct ipq *next; /* linked list pointers */
+ struct list_head lru_list; /* lru list member */
u32 saddr;
u32 daddr;
u16 id;
@@ -94,6 +97,7 @@
/* Per-bucket lock is easy to add now. */
static struct ipq *ipq_hash[IPQ_HASHSZ];
static rwlock_t ipfrag_lock = RW_LOCK_UNLOCKED;
+static LIST_HEAD(ipq_lru_list);
int ip_frag_nqueues = 0;
static __inline__ void __ipq_unlink(struct ipq *qp)
@@ -101,6 +105,7 @@
if(qp->next)
qp->next->pprev = qp->pprev;
*qp->pprev = qp->next;
+ list_del(&qp->lru_list);
ip_frag_nqueues--;
}
@@ -202,39 +207,30 @@
*/
static void ip_evictor(void)
{
- int i, progress;
+ struct ipq *qp;
+ struct list_head *tmp;
- do {
+ for(;;) {
if (atomic_read(&ip_frag_mem) <= sysctl_ipfrag_low_thresh)
return;
- progress = 0;
- /* FIXME: Make LRU queue of frag heads. -DaveM */
- for (i = 0; i < IPQ_HASHSZ; i++) {
- struct ipq *qp;
- if (ipq_hash[i] == NULL)
- continue;
-
- read_lock(&ipfrag_lock);
- if ((qp = ipq_hash[i]) != NULL) {
- /* find the oldest queue for this hash bucket */
- while (qp->next)
- qp = qp->next;
- atomic_inc(&qp->refcnt);
- read_unlock(&ipfrag_lock);
-
- spin_lock(&qp->lock);
- if (!(qp->last_in&COMPLETE))
- ipq_kill(qp);
- spin_unlock(&qp->lock);
-
- ipq_put(qp);
- IP_INC_STATS_BH(IpReasmFails);
- progress = 1;
- continue;
- }
+ read_lock(&ipfrag_lock);
+ if (list_empty(&ipq_lru_list)) {
read_unlock(&ipfrag_lock);
+ return;
}
- } while (progress);
+ tmp = ipq_lru_list.next;
+ qp = list_entry(tmp, struct ipq, lru_list);
+ atomic_inc(&qp->refcnt);
+ read_unlock(&ipfrag_lock);
+
+ spin_lock(&qp->lock);
+ if (!(qp->last_in&COMPLETE))
+ ipq_kill(qp);
+ spin_unlock(&qp->lock);
+
+ ipq_put(qp);
+ IP_INC_STATS_BH(IpReasmFails);
+ }
}
/*
@@ -302,6 +298,8 @@
qp->next->pprev = &qp->next;
ipq_hash[hash] = qp;
qp->pprev = &ipq_hash[hash];
+ INIT_LIST_HEAD(&qp->lru_list);
+ list_add_tail(&qp->lru_list, &ipq_lru_list);
ip_frag_nqueues++;
write_unlock(&ipfrag_lock);
return qp;
@@ -496,6 +494,10 @@
if (offset == 0)
qp->last_in |= FIRST_IN;
+ write_lock(&ipfrag_lock);
+ list_move_tail(&qp->lru_list, &ipq_lru_list);
+ write_unlock(&ipfrag_lock);
+
return;
err:
diff -urN ../ppp_filter/linux/linux-2.4.20-clean/net/ipv6/reassembly.c linux-2.4.20/net/ipv6/reassembly.c
--- ../ppp_filter/linux/linux-2.4.20-clean/net/ipv6/reassembly.c 2002-11-29 00:53:15.000000000 +0100
+++ linux-2.4.20/net/ipv6/reassembly.c 2003-02-16 05:39:50.000000000 +0100
@@ -22,6 +22,7 @@
*
* Horst von Brand Add missing #include <linux/string.h>
* Alexey Kuznetsov SMP races, threading, cleanup.
+ * Patrick McHardy LRU queue of frag heads for evictor.
*/
#include <linux/config.h>
#include <linux/errno.h>
@@ -30,6 +31,7 @@
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/sched.h>
+#include <linux/list.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/in6.h>
@@ -67,6 +69,7 @@
struct frag_queue
{
struct frag_queue *next;
+ struct list_head lru_list; /* lru list member */
__u32 id; /* fragment id */
struct in6_addr saddr;
@@ -95,6 +98,7 @@
static struct frag_queue *ip6_frag_hash[IP6Q_HASHSZ];
static rwlock_t ip6_frag_lock = RW_LOCK_UNLOCKED;
+static LIST_HEAD(ip6_frag_lru_list);
int ip6_frag_nqueues = 0;
static __inline__ void __fq_unlink(struct frag_queue *fq)
@@ -102,6 +106,7 @@
if(fq->next)
fq->next->pprev = fq->pprev;
*fq->pprev = fq->next;
+ list_del(&fq->lru_list);
ip6_frag_nqueues--;
}
@@ -193,38 +198,30 @@
static void ip6_evictor(void)
{
- int i, progress;
+ struct frag_queue *fq;
+ struct list_head *tmp;
- do {
+ for(;;) {
if (atomic_read(&ip6_frag_mem) <= sysctl_ip6frag_low_thresh)
return;
- progress = 0;
- for (i = 0; i < IP6Q_HASHSZ; i++) {
- struct frag_queue *fq;
- if (ip6_frag_hash[i] == NULL)
- continue;
-
- read_lock(&ip6_frag_lock);
- if ((fq = ip6_frag_hash[i]) != NULL) {
- /* find the oldest queue for this hash bucket */
- while (fq->next)
- fq = fq->next;
- atomic_inc(&fq->refcnt);
- read_unlock(&ip6_frag_lock);
-
- spin_lock(&fq->lock);
- if (!(fq->last_in&COMPLETE))
- fq_kill(fq);
- spin_unlock(&fq->lock);
-
- fq_put(fq);
- IP6_INC_STATS_BH(Ip6ReasmFails);
- progress = 1;
- continue;
- }
+ read_lock(&ip6_frag_lock);
+ if (list_empty(&ip6_frag_lru_list)) {
read_unlock(&ip6_frag_lock);
+ return;
}
- } while (progress);
+ tmp = ip6_frag_lru_list.next;
+ fq = list_entry(tmp, struct frag_queue, lru_list);
+ atomic_inc(&fq->refcnt);
+ read_unlock(&ip6_frag_lock);
+
+ spin_lock(&fq->lock);
+ if (!(fq->last_in&COMPLETE))
+ fq_kill(fq);
+ spin_unlock(&fq->lock);
+
+ fq_put(fq);
+ IP6_INC_STATS_BH(Ip6ReasmFails);
+ }
}
static void ip6_frag_expire(unsigned long data)
@@ -294,6 +291,8 @@
fq->next->pprev = &fq->next;
ip6_frag_hash[hash] = fq;
fq->pprev = &ip6_frag_hash[hash];
+ INIT_LIST_HEAD(&fq->lru_list);
+ list_add_tail(&fq->lru_list, &ip6_frag_lru_list);
ip6_frag_nqueues++;
write_unlock(&ip6_frag_lock);
return fq;
@@ -501,6 +500,9 @@
fq->nhoffset = nhoff;
fq->last_in |= FIRST_IN;
}
+ write_lock(&ip6_frag_lock);
+ list_move_tail(&fq->lru_list, &ip6_frag_lru_list);
+ write_unlock(&ip6_frag_lock);
return;
err:
