[PATCH] nl80211: Optimize cfg80211_bss_expire invocations

[PATCH] nl80211: Optimize cfg80211_bss_expire invocations

[Denis Kenzior]

Only invoke cfg80211_bss_expire on the first nl80211_dump_scan
invocation to avoid (likely) redundant processing.

Signed-off-by: Denis Kenzior <denkenz@gmail.com>
---
 net/wireless/nl80211.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index ff28f8feeb09..7458cbcf00b2 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -7930,7 +7930,15 @@ static int nl80211_dump_scan(struct sk_buff *skb, struct netlink_callback *cb)
 
 	wdev_lock(wdev);
 	spin_lock_bh(&rdev->bss_lock);
-	cfg80211_bss_expire(rdev);
+
+	/*
+	 * dump_scan will be called multiple times to break up the scan results
+	 * into multiple messages.  It is unlikely that any more bss-es will be
+	 * expired after the first call, so only call only call this on the
+	 * first dump_scan invocation.
+	 */
+	if (start == 0)
+		cfg80211_bss_expire(rdev);
 
 	cb->seq = rdev->bss_generation;
 
-- 
2.13.5