summaryrefslogtreecommitdiff
path: root/drivers/net/wireless/ath/carl9170
diff options
context:
space:
mode:
authorAndreea-Cristina Bernat <bernat.ada@gmail.com>2014-08-27 17:27:30 +0400
committerJohn W. Linville <linville@tuxdriver.com>2014-08-28 22:50:13 +0400
commit6a5d088a923854569e20eac4f3f569926d5911ec (patch)
treeb3ce027b9dc733425722447847c97563d7ab477a /drivers/net/wireless/ath/carl9170
parent1a7c5b7ef0cf93b42b9181973ce283fe77fb6093 (diff)
downloadlinux-6a5d088a923854569e20eac4f3f569926d5911ec.tar.xz
carl9170: tx: Replace rcu_assign_pointer() with RCU_INIT_POINTER()
According to RCU_INIT_POINTER()'s block comment 3.a, it can be used if "3. The referenced data structure has already been exposed to readers either at compile time or via rcu_assign_pointer() -and- a. You have not made -any- reader-visible changes to this structure since then". This case fulfills the conditions above because between the rcu_dereference() call (cvif = rcu_dereference(ar->beacon_iter);) and the rcu_assign_pointer() call there is no update of the "cvif" variable. Therefore, this patch makes the replacement. The following Coccinelle semantic patch was used: @@ identifier v; @@ v = rcu_dereference(...); ... when != rcu_dereference(...); when != v = ...; when != (<+...v...+>)++; when != \(memcpy\|memset\)(...); ( - rcu_assign_pointer + RCU_INIT_POINTER (..., v); | if(...) { ... when != v = ...; - rcu_assign_pointer + RCU_INIT_POINTER (..., v); ... when any } ) Because there are cases where between a “rcu_dereference()” call and a “rcu_assign_pointer()” call might be updates of the value that interests us, the Coccinelle semantic patch ignores them and replaces with "RCU_INIT_POINTER()" only when the update is not happening. Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com> Acked-by: Christian Lamparter <chunkeey@googlemail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers/net/wireless/ath/carl9170')
-rw-r--r--drivers/net/wireless/ath/carl9170/tx.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/wireless/ath/carl9170/tx.c b/drivers/net/wireless/ath/carl9170/tx.c
index 4cadfd48ffdf..ae86a600d920 100644
--- a/drivers/net/wireless/ath/carl9170/tx.c
+++ b/drivers/net/wireless/ath/carl9170/tx.c
@@ -1557,7 +1557,7 @@ static struct carl9170_vif_info *carl9170_pick_beaconing_vif(struct ar9170 *ar)
}
out:
- rcu_assign_pointer(ar->beacon_iter, cvif);
+ RCU_INIT_POINTER(ar->beacon_iter, cvif);
return cvif;
}