netem: dont call vfree() under spinlock and BH disabled

commit 6373a9a286 (netem: use vmalloc for distribution table) added a
regression, since vfree() is called while holding a spinlock and BH
being disabled.

Fix this by doing the pointers swap in critical section, and freeing
after spinlock release.

Also add __GFP_NOWARN to the kmalloc() try, since we fallback to
vmalloc().

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2011-12-23 19:28:51 +00:00 committed by David S. Miller
parent 5f0a6e2d50
commit bb52c7acf8
1 changed files with 4 additions and 3 deletions

View File

@ -488,7 +488,7 @@ static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr)
return -EINVAL;
s = sizeof(struct disttable) + n * sizeof(s16);
d = kmalloc(s, GFP_KERNEL);
d = kmalloc(s, GFP_KERNEL | __GFP_NOWARN);
if (!d)
d = vmalloc(s);
if (!d)
@ -501,9 +501,10 @@ static int get_dist_table(struct Qdisc *sch, const struct nlattr *attr)
root_lock = qdisc_root_sleeping_lock(sch);
spin_lock_bh(root_lock);
dist_free(q->delay_dist);
q->delay_dist = d;
swap(q->delay_dist, d);
spin_unlock_bh(root_lock);
dist_free(d);
return 0;
}