diff options
| author | Eric Dumazet <edumazet@google.com> | 2013-10-30 13:10:44 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-11-03 23:19:00 -0500 |
| commit | 74d332c13b2148ae934ea94dac1745ae92efe8e5 (patch) | |
| tree | 4f8f287774deaba28fa4c85d085d587ae7515aaf /Documentation/networking | |
| parent | b397f99921827e114d7f5600447e172a99c50165 (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 'Documentation/networking')
| -rw-r--r-- | Documentation/networking/netdevices.txt | 10 |
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. |