From 74d332c13b2148ae934ea94dac1745ae92efe8e5 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 30 Oct 2013 13:10:44 -0700 Subject: 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 Reported-by: Joby Poriyath Cc: Ben Hutchings Signed-off-by: David S. Miller --- net/core/dev.c | 22 +++++++++++++++++----- net/core/net-sysfs.c | 2 +- 2 files changed, 18 insertions(+), 6 deletions(-) (limited to 'net/core') diff --git a/net/core/dev.c b/net/core/dev.c index 0054c8c..0e61365 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6196,6 +6196,16 @@ void netdev_set_default_ethtool_ops(struct net_device *dev, } EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); +void netdev_freemem(struct net_device *dev) +{ + char *addr = (char *)dev - dev->padded; + + if (is_vmalloc_addr(addr)) + vfree(addr); + else + kfree(addr); +} + /** * alloc_netdev_mqs - allocate network device * @sizeof_priv: size of private data to allocate space for @@ -6239,7 +6249,9 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, /* ensure 32-byte alignment of whole construct */ alloc_size += NETDEV_ALIGN - 1; - p = kzalloc(alloc_size, GFP_KERNEL); + p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + if (!p) + p = vzalloc(alloc_size); if (!p) return NULL; @@ -6248,7 +6260,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, dev->pcpu_refcnt = alloc_percpu(int); if (!dev->pcpu_refcnt) - goto free_p; + goto free_dev; if (dev_addr_init(dev)) goto free_pcpu; @@ -6301,8 +6313,8 @@ free_pcpu: kfree(dev->_rx); #endif -free_p: - kfree(p); +free_dev: + netdev_freemem(dev); return NULL; } EXPORT_SYMBOL(alloc_netdev_mqs); @@ -6339,7 +6351,7 @@ void free_netdev(struct net_device *dev) /* Compatibility with error handling in drivers */ if (dev->reg_state == NETREG_UNINITIALIZED) { - kfree((char *)dev - dev->padded); + netdev_freemem(dev); return; } diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index d954b56..d03f2c9 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1263,7 +1263,7 @@ static void netdev_release(struct device *d) BUG_ON(dev->reg_state != NETREG_RELEASED); kfree(dev->ifalias); - kfree((char *)dev - dev->padded); + netdev_freemem(dev); } static const void *net_namespace(struct device *d) -- cgit v1.1