pull bumping refcount into ->kill()

there will be one more change of ->kill() calling conventions; this
isn't final.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 0 deletions

diff --git a/kernel/acct.c b/kernel/acct.c
index 7bb9e659a7da..a74f3d1a0c26 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -189,6 +189,12 @@ static void acct_pin_kill(struct fs_pin *pin)
 {
 	struct bsd_acct_struct *acct;
 	acct = container_of(pin, struct bsd_acct_struct, pin);
+	if (!atomic_long_inc_not_zero(&pin->count)) {
+		rcu_read_unlock();
+		cpu_relax();
+		return;
+	}
+	rcu_read_unlock();
 	mutex_lock(&acct->lock);
 	if (!acct->ns) {
 		mutex_unlock(&acct->lock);