Commit d433673e authored by Jesper Dangaard Brouer's avatar Jesper Dangaard Brouer Committed by David S. Miller
Browse files

net: frag helper functions for mem limit tracking 



This change is primarily a preparation to ease the extension of memory
limit tracking.

The change does reduce the number atomic operation, during freeing of
a frag queue.  This does introduce a some performance improvement, as
these atomic operations are at the core of the performance problems
seen on NUMA systems.

Signed-off-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6e34a8b3

include/net/inet_frag.h

+27 −0
Original line number Diff line number Diff line
@@ -79,4 +79,31 @@ static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f 
		inet_frag_destroy(q, f, NULL);

}



/* Memory Tracking Functions. */



static inline int frag_mem_limit(struct netns_frags *nf)

{

	return atomic_read(&nf->mem);

}



static inline void sub_frag_mem_limit(struct inet_frag_queue *q, int i)

{

	atomic_sub(i, &q->net->mem);

}



static inline void add_frag_mem_limit(struct inet_frag_queue *q, int i)

{

	atomic_add(i, &q->net->mem);

}



static inline void init_frag_mem_limit(struct netns_frags *nf)

{

	atomic_set(&nf->mem, 0);

}



static inline int sum_frag_mem_limit(struct netns_frags *nf)

{

	return atomic_read(&nf->mem);

}



#endif

include/net/ipv6.h

+1 −1
Original line number Diff line number Diff line
@@ -288,7 +288,7 @@ static inline int ip6_frag_nqueues(struct net *net) 


static inline int ip6_frag_mem(struct net *net)

{

	return atomic_read(&net->ipv6.frags.mem);

	return sum_frag_mem_limit(&net->ipv6.frags);

}

#endif

net/ipv4/inet_fragment.c

+12 −13
Original line number Diff line number Diff line
@@ -73,7 +73,7 @@ EXPORT_SYMBOL(inet_frags_init); 
void inet_frags_init_net(struct netns_frags *nf)

{

	nf->nqueues = 0;

	atomic_set(&nf->mem, 0);

	init_frag_mem_limit(nf);

	INIT_LIST_HEAD(&nf->lru_list);

}

EXPORT_SYMBOL(inet_frags_init_net);
@@ -117,12 +117,8 @@ void inet_frag_kill(struct inet_frag_queue *fq, struct inet_frags *f) 
EXPORT_SYMBOL(inet_frag_kill);



static inline void frag_kfree_skb(struct netns_frags *nf, struct inet_frags *f,

		struct sk_buff *skb, int *work)

		struct sk_buff *skb)

{

	if (work)

		*work -= skb->truesize;



	atomic_sub(skb->truesize, &nf->mem);

	if (f->skb_free)

		f->skb_free(skb);

	kfree_skb(skb);
@@ -133,6 +129,7 @@ void inet_frag_destroy(struct inet_frag_queue *q, struct inet_frags *f, 
{

	struct sk_buff *fp;

	struct netns_frags *nf;

	unsigned int sum, sum_truesize = 0;



	WARN_ON(!(q->last_in & INET_FRAG_COMPLETE));

	WARN_ON(del_timer(&q->timer) != 0);
@@ -143,13 +140,14 @@ void inet_frag_destroy(struct inet_frag_queue *q, struct inet_frags *f, 
	while (fp) {

		struct sk_buff *xp = fp->next;



		frag_kfree_skb(nf, f, fp, work);

		sum_truesize += fp->truesize;

		frag_kfree_skb(nf, f, fp);

		fp = xp;

	}



	sum = sum_truesize + f->qsize;

	if (work)

		*work -= f->qsize;

	atomic_sub(f->qsize, &nf->mem);

		*work -= sum;

	sub_frag_mem_limit(q, sum);



	if (f->destructor)

		f->destructor(q);
@@ -164,11 +162,11 @@ int inet_frag_evictor(struct netns_frags *nf, struct inet_frags *f, bool force) 
	int work, evicted = 0;



	if (!force) {

		if (atomic_read(&nf->mem) <= nf->high_thresh)

		if (frag_mem_limit(nf) <= nf->high_thresh)

			return 0;

	}



	work = atomic_read(&nf->mem) - nf->low_thresh;

	work = frag_mem_limit(nf) - nf->low_thresh;

	while (work > 0) {

		read_lock(&f->lock);

		if (list_empty(&nf->lru_list)) {
@@ -250,7 +248,8 @@ static struct inet_frag_queue *inet_frag_alloc(struct netns_frags *nf, 


	q->net = nf;

	f->constructor(q, arg);

	atomic_add(f->qsize, &nf->mem);

	add_frag_mem_limit(q, f->qsize);



	setup_timer(&q->timer, f->frag_expire, (unsigned long)q);

	spin_lock_init(&q->lock);

	atomic_set(&q->refcnt, 1);

net/ipv4/ip_fragment.c

+11 −13
Original line number Diff line number Diff line
@@ -122,7 +122,7 @@ int ip_frag_nqueues(struct net *net) 


int ip_frag_mem(struct net *net)

{

	return atomic_read(&net->ipv4.frags.mem);

	return sum_frag_mem_limit(&net->ipv4.frags);

}



static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
@@ -161,13 +161,6 @@ static bool ip4_frag_match(struct inet_frag_queue *q, void *a) 
		qp->user == arg->user;

}



/* Memory Tracking Functions. */

static void frag_kfree_skb(struct netns_frags *nf, struct sk_buff *skb)

{

	atomic_sub(skb->truesize, &nf->mem);

	kfree_skb(skb);

}



static void ip4_frag_init(struct inet_frag_queue *q, void *a)

{

	struct ipq *qp = container_of(q, struct ipq, q);
@@ -340,6 +333,7 @@ static inline int ip_frag_too_far(struct ipq *qp) 
static int ip_frag_reinit(struct ipq *qp)

{

	struct sk_buff *fp;

	unsigned int sum_truesize = 0;



	if (!mod_timer(&qp->q.timer, jiffies + qp->q.net->timeout)) {

		atomic_inc(&qp->q.refcnt);
@@ -349,9 +343,12 @@ static int ip_frag_reinit(struct ipq *qp) 
	fp = qp->q.fragments;

	do {

		struct sk_buff *xp = fp->next;

		frag_kfree_skb(qp->q.net, fp);



		sum_truesize += fp->truesize;

		kfree_skb(fp);

		fp = xp;

	} while (fp);

	sub_frag_mem_limit(&qp->q, sum_truesize);



	qp->q.last_in = 0;

	qp->q.len = 0;
@@ -496,7 +493,8 @@ found: 
				qp->q.fragments = next;



			qp->q.meat -= free_it->len;

			frag_kfree_skb(qp->q.net, free_it);

			sub_frag_mem_limit(&qp->q, free_it->truesize);

			kfree_skb(free_it);

		}

	}
@@ -519,7 +517,7 @@ found: 
	qp->q.stamp = skb->tstamp;

	qp->q.meat += skb->len;

	qp->ecn |= ecn;

	atomic_add(skb->truesize, &qp->q.net->mem);

	add_frag_mem_limit(&qp->q, skb->truesize);

	if (offset == 0)

		qp->q.last_in |= INET_FRAG_FIRST_IN;
@@ -617,7 +615,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 
		head->len -= clone->len;

		clone->csum = 0;

		clone->ip_summed = head->ip_summed;

		atomic_add(clone->truesize, &qp->q.net->mem);

		add_frag_mem_limit(&qp->q, clone->truesize);

	}



	skb_push(head, head->data - skb_network_header(head));
@@ -645,7 +643,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, 
		}

		fp = next;

	}

	atomic_sub(sum_truesize, &qp->q.net->mem);

	sub_frag_mem_limit(&qp->q, sum_truesize);



	head->next = NULL;

	head->dev = dev;

net/ipv6/netfilter/nf_conntrack_reasm.c

+3 −3
Original line number Diff line number Diff line
@@ -319,7 +319,7 @@ found: 
	fq->q.meat += skb->len;

	if (payload_len > fq->q.max_size)

		fq->q.max_size = payload_len;

	atomic_add(skb->truesize, &fq->q.net->mem);

	add_frag_mem_limit(&fq->q, skb->truesize);



	/* The first fragment.

	 * nhoffset is obtained from the first fragment, of course.
@@ -398,7 +398,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct net_device *dev) 
		clone->ip_summed = head->ip_summed;



		NFCT_FRAG6_CB(clone)->orig = NULL;

		atomic_add(clone->truesize, &fq->q.net->mem);

		add_frag_mem_limit(&fq->q, clone->truesize);

	}



	/* We have to remove fragment header from datagram and to relocate
@@ -422,7 +422,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct net_device *dev) 
			head->csum = csum_add(head->csum, fp->csum);

		head->truesize += fp->truesize;

	}

	atomic_sub(head->truesize, &fq->q.net->mem);

	sub_frag_mem_limit(&fq->q, head->truesize);



	head->local_df = 1;

	head->next = NULL;

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