AUDIT: Reduce contention in audit_serial()
... by generating serial numbers only if an audit context is actually
_used_, rather than doing so at syscall entry even when the context
isn't necessarily marked auditable.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/kernel/audit.c b/kernel/audit.c
index 27ffcf3..d321e25 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -625,7 +625,9 @@
unsigned int ret;
spin_lock_irqsave(&serial_lock, flags);
- ret = serial++;
+ do {
+ ret = ++serial;
+ } while (unlikely(!ret));
spin_unlock_irqrestore(&serial_lock, flags);
return ret;
