[PATCH 2/2] netprio_cgroup: Optimize the priomap copy loop slightly
From: Srivatsa S. Bhat <hidden>
Date: 2012-09-11 11:23:11
Also in:
lkml
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
* Check for non-NULL old_priomap outside the loop, since its not going to change. * Copy the old_priomap's length to a local variable and use that for loop control, instead of costly pointer-dereferences. Signed-off-by: Srivatsa S. Bhat <redacted> --- net/core/netprio_cgroup.c | 12 +++++++----- 1 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index fd339bb0..0775bc9 100644
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c@@ -73,7 +73,7 @@ static int extend_netdev_table(struct net_device *dev, u32 new_len) ((sizeof(u32) * new_len)); struct netprio_map *new_priomap = kzalloc(new_size, GFP_KERNEL); struct netprio_map *old_priomap; - int i; + int i, old_len; old_priomap = rtnl_dereference(dev->priomap);
@@ -82,10 +82,12 @@ static int extend_netdev_table(struct net_device *dev, u32 new_len) return -ENOMEM; } - for (i = 0; - old_priomap && (i < old_priomap->priomap_len); - i++) - new_priomap->priomap[i] = old_priomap->priomap[i]; + if (old_priomap) { + old_len = old_priomap->priomap_len; + + for (i = 0; i < old_len; i++) + new_priomap->priomap[i] = old_priomap->priomap[i]; + } new_priomap->priomap_len = new_len;