p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

xfrm: state: don't use lock anymore unless acquire operation is needed 

push the lock down, after earlier patches we can rely on rcu to
make sure state struct won't go away.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This commit is contained in:
Florian Westphal 2016-08-09 12:16:09 +02:00 committed by Steffen Klassert
parent c8406998b8
commit d737a58055
2 changed files with 7 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
include/net/netns/xfrm.h
View File

@ -38,9 +38,9 @@ struct netns_xfrm {
* mode. Also, it can be used by ah/esp icmp error handler to find
* offending SA.
*/
struct hlist_head *state_bydst;
struct hlist_head *state_bysrc;
struct hlist_head *state_byspi;
struct hlist_head __rcu *state_bydst;
struct hlist_head __rcu *state_bysrc;
struct hlist_head __rcu *state_byspi;
unsigned int state_hmask;
unsigned int state_num;
struct work_struct state_hash_work;

6
net/xfrm/xfrm_state.c
View File

@ -799,7 +799,7 @@ xfrm_state_find(const xfrm_address_t *daddr, const xfrm_address_t *saddr,
sequence = read_seqcount_begin(&xfrm_state_hash_generation);
spin_lock_bh(&net->xfrm.xfrm_state_lock);
rcu_read_lock();
h = xfrm_dst_hash(net, daddr, saddr, tmpl->reqid, encap_family);
hlist_for_each_entry_rcu(x, net->xfrm.state_bydst + h, bydst) {
if (x->props.family == encap_family &&
@ -870,6 +870,7 @@ xfrm_state_find(const xfrm_address_t *daddr, const xfrm_address_t *saddr,
}
if (km_query(x, tmpl, pol) == 0) {
spin_lock_bh(&net->xfrm.xfrm_state_lock);
x->km.state = XFRM_STATE_ACQ;
list_add(&x->km.all, &net->xfrm.state_all);
hlist_add_head_rcu(&x->bydst, net->xfrm.state_bydst + h);
@ -883,6 +884,7 @@ xfrm_state_find(const xfrm_address_t *daddr, const xfrm_address_t *saddr,
tasklet_hrtimer_start(&x->mtimer, ktime_set(net->xfrm.sysctl_acq_expires, 0), HRTIMER_MODE_REL);
net->xfrm.state_num++;
xfrm_hash_grow_check(net, x->bydst.next != NULL);
spin_unlock_bh(&net->xfrm.xfrm_state_lock);
} else {
x->km.state = XFRM_STATE_DEAD;
to_put = x;
@ -899,7 +901,7 @@ xfrm_state_find(const xfrm_address_t *daddr, const xfrm_address_t *saddr,
} else {
*err = acquire_in_progress ? -EAGAIN : error;
}
spin_unlock_bh(&net->xfrm.xfrm_state_lock);
rcu_read_unlock();
if (to_put)
xfrm_state_put(to_put);