Commit 6373a9a2 authored by stephen hemminger's avatar stephen hemminger Committed by David S. Miller
Browse files

netem: use vmalloc for distribution table 



The netem probability table can be large (up to 64K bytes)
which may be too large to allocate in one contiguous chunk.

Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 861d7f74

net/sched/sch_netem.c

+18 −4
Original line number Diff line number Diff line
@@ -308,6 +308,16 @@ static void netem_reset(struct Qdisc *sch) 
	qdisc_watchdog_cancel(&q->watchdog);

}



static void dist_free(struct disttable *d)

{

	if (d) {

		if (is_vmalloc_addr(d))

			vfree(d);

		else

			kfree(d);

	}

}



/*

 * Distribution data is a variable size payload containing

 * signed 16 bit values.
@@ -315,16 +325,20 @@ static void netem_reset(struct Qdisc *sch) 
static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr)

{

	struct netem_sched_data *q = qdisc_priv(sch);

	unsigned long n = nla_len(attr)/sizeof(__s16);

	size_t n = nla_len(attr)/sizeof(__s16);

	const __s16 *data = nla_data(attr);

	spinlock_t *root_lock;

	struct disttable *d;

	int i;

	size_t s;



	if (n > 65536)

		return -EINVAL;



	d = kmalloc(sizeof(*d) + n*sizeof(d->table[0]), GFP_KERNEL);

	s = sizeof(struct disttable) + n * sizeof(s16);

	d = kmalloc(s, GFP_KERNEL);

	if (!d)

		d = vmalloc(s);

	if (!d)

		return -ENOMEM;
@@ -335,7 +349,7 @@ static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr) 
	root_lock = qdisc_root_sleeping_lock(sch);



	spin_lock_bh(root_lock);

	kfree(q->delay_dist);

	dist_free(q->delay_dist);

	q->delay_dist = d;

	spin_unlock_bh(root_lock);

	return 0;
@@ -556,7 +570,7 @@ static void netem_destroy(struct Qdisc *sch) 


	qdisc_watchdog_cancel(&q->watchdog);

	qdisc_destroy(q->qdisc);

	kfree(q->delay_dist);

	dist_free(q->delay_dist);

}



static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)