[RFC 3/4] net/fib: Check budget before should_{inflate,halve}()

From: Dmitry Safonov
Date: Tue Mar 26 2019 - 11:30:39 EST


Those functions are compute-costly, if we're out of budget - better
omit additional computations.

Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
---
net/ipv4/fib_trie.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index d90cf9dfd443..2ce2739e7693 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -868,7 +868,7 @@ static struct key_vector *resize(struct trie *t, struct key_vector *tn,
/* Double as long as the resulting node has a number of
* nonempty nodes that are above the threshold.
*/
- while (should_inflate(tp, tn) && *budget) {
+ while (*budget && should_inflate(tp, tn)) {
tp = inflate(t, tn, budget);
if (!tp) {
#ifdef CONFIG_IP_FIB_TRIE_STATS
@@ -894,7 +894,7 @@ static struct key_vector *resize(struct trie *t, struct key_vector *tn,
/* Halve as long as the number of empty children in this
* node is above threshold.
*/
- while (should_halve(tp, tn) && *budget) {
+ while (*budget && should_halve(tp, tn)) {
tp = halve(t, tn, budget);
if (!tp) {
#ifdef CONFIG_IP_FIB_TRIE_STATS
--
2.21.0