bql: Fix POSDIFF() to integer overflow aware.

POSDIFF() fails to take into account integer overflow case.

Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Denys Fedoryshchenko <denys@visp.net.lb>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Hiroaki SHIMODA 2012-05-30 12:24:39 +00:00 committed by David S. Miller
parent 401453a31e
commit 0cfd32b736

View File

@ -10,7 +10,7 @@
#include <linux/jiffies.h>
#include <linux/dynamic_queue_limits.h>
#define POSDIFF(A, B) ((A) > (B) ? (A) - (B) : 0)
#define POSDIFF(A, B) ((int)((A) - (B)) > 0 ? (A) - (B) : 0)
/* Records completed count and recalculates the queue limit */
void dql_completed(struct dql *dql, unsigned int count)