path: root/Documentation/networking/netdevices.txt
diff options
authorEric Dumazet <edumazet@google.com>2013-10-30 13:10:44 -0700
committerDavid S. Miller <davem@davemloft.net>2013-11-03 23:19:00 -0500
commit74d332c13b2148ae934ea94dac1745ae92efe8e5 (patch)
tree4f8f287774deaba28fa4c85d085d587ae7515aaf /Documentation/networking/netdevices.txt
parentMerge branch 'sctp_csum' (diff)
net: extend net_device allocation to vmalloc()
Joby Poriyath provided a xen-netback patch to reduce the size of xenvif structure as some netdev allocation could fail under memory pressure/fragmentation. This patch is handling the problem at the core level, allowing any netdev structures to use vmalloc() if kmalloc() failed. As vmalloc() adds overhead on a critical network path, add __GFP_REPEAT to kzalloc() flags to do this fallback only when really needed. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Joby Poriyath <joby.poriyath@citrix.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
1 files changed, 5 insertions, 5 deletions
diff --git a/Documentation/networking/netdevices.txt b/Documentation/networking/netdevices.txt
index c7ecc7080494..0b1cf6b2a592 100644
--- a/Documentation/networking/netdevices.txt
+++ b/Documentation/networking/netdevices.txt
@@ -10,12 +10,12 @@ network devices.
struct net_device allocation rules
Network device structures need to persist even after module is unloaded and
-must be allocated with kmalloc. If device has registered successfully,
-it will be freed on last use by free_netdev. This is required to handle the
-pathologic case cleanly (example: rmmod mydriver </sys/class/net/myeth/mtu )
+must be allocated with alloc_netdev_mqs() and friends.
+If device has registered successfully, it will be freed on last use
+by free_netdev(). This is required to handle the pathologic case cleanly
+(example: rmmod mydriver </sys/class/net/myeth/mtu )
-There are routines in net_init.c to handle the common cases of
-alloc_etherdev, alloc_netdev. These reserve extra space for driver
+alloc_netdev_mqs()/alloc_netdev() reserve extra space for driver
private data which gets freed when the network device is freed. If
separately allocated data is attached to the network device
(netdev_priv(dev)) then it is up to the module exit handler to free that.