[ovs-dev] [PATCH 6/7] datapath: Factor out allocation and verification of actions.
Jesse Gross
jesse at nicira.com
Tue Jun 10 23:47:17 UTC 2014
As the size of the flow key grows, it can put some pressure on the
stack. This is particularly true in ovs_flow_cmd_set(), which needs several
copies of the key on the stack. One of those uses is logically separate,
so this factors it out to reduce stack pressure and improve readibility.
Signed-off-by: Jesse Gross <jesse at nicira.com>
---
datapath/datapath.c | 38 ++++++++++++++++++++++++++------------
1 file changed, 26 insertions(+), 12 deletions(-)
diff --git a/datapath/datapath.c b/datapath/datapath.c
index 81ecc0f..305936a 100644
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -952,11 +952,34 @@ error:
return error;
}
+static struct sw_flow_actions *get_flow_actions(const struct nlattr *a,
+ const struct sw_flow_key *key,
+ const struct sw_flow_mask *mask)
+{
+ struct sw_flow_actions *acts;
+ struct sw_flow_key masked_key;
+ int error;
+
+ acts = ovs_nla_alloc_flow_actions(nla_len(a));
+ if (IS_ERR(acts))
+ return acts;
+
+ ovs_flow_mask_key(&masked_key, key, mask);
+ error = ovs_nla_copy_actions(a, &masked_key, 0, &acts);
+ if (error) {
+ OVS_NLERR("Flow actions may not be safe on all matching packets.\n");
+ kfree(acts);
+ return ERR_PTR(error);
+ }
+
+ return acts;
+}
+
static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr **a = info->attrs;
struct ovs_header *ovs_header = info->userhdr;
- struct sw_flow_key key, masked_key;
+ struct sw_flow_key key;
struct sw_flow *flow;
struct sw_flow_mask mask;
struct sk_buff *reply = NULL;
@@ -978,20 +1001,11 @@ static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
/* Validate actions. */
if (a[OVS_FLOW_ATTR_ACTIONS]) {
- acts = ovs_nla_alloc_flow_actions(nla_len(a[OVS_FLOW_ATTR_ACTIONS]));
- error = PTR_ERR(acts);
+ acts = get_flow_actions(a[OVS_FLOW_ATTR_ACTIONS], &key, &mask);
if (IS_ERR(acts))
goto error;
-
- ovs_flow_mask_key(&masked_key, &key, &mask);
- error = ovs_nla_copy_actions(a[OVS_FLOW_ATTR_ACTIONS],
- &masked_key, 0, &acts);
- if (error) {
- OVS_NLERR("Flow actions may not be safe on all matching packets.\n");
- goto err_kfree_acts;
- }
}
-
+
/* Can allocate before locking if have acts. */
if (acts) {
reply = ovs_flow_cmd_alloc_info(acts, info, false);
--
1.9.1
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