OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

IPV4: fib_trie use vmalloc for large tnodes 

Use vmalloc rather than alloc_pages to avoid wasting memory.
The problem is that tnode structure has a power of 2 sized array,
plus a header. So the current code wastes almost half the memory
allocated because it always needs the next bigger size to hold
that small header.

This is similar to an earlier patch by Eric, but instead of a list
and lock, I used a workqueue to handle the fact that vfree can't
be done in interrupt context.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger 2008-04-10 02:56:38 -07:00 committed by David S. Miller
parent 5c06f510a2
commit 15be75cdb5
1 changed files with 15 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
net/ipv4/fib_trie.c
View File

@ -122,7 +122,10 @@ struct tnode {
unsigned char bits; /* 2log(KEYLENGTH) bits needed */
unsigned int full_children; /* KEYLENGTH bits needed */
unsigned int empty_children; /* KEYLENGTH bits needed */
struct rcu_head rcu;
union {
struct rcu_head rcu;
struct work_struct work;
};
struct node *child[0];
};
@ -346,16 +349,16 @@ static inline void free_leaf_info(struct leaf_info *leaf)
static struct tnode *tnode_alloc(size_t size)
{
struct page *pages;
if (size <= PAGE_SIZE)
return kzalloc(size, GFP_KERNEL);
else
return __vmalloc(size, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL);
}
pages = alloc_pages(GFP_KERNEL|__GFP_ZERO, get_order(size));
if (!pages)
return NULL;
return page_address(pages);
static void __tnode_vfree(struct work_struct *arg)
{
struct tnode *tn = container_of(arg, struct tnode, work);
vfree(tn);
}
static void __tnode_free_rcu(struct rcu_head *head)
@ -366,8 +369,10 @@ static void __tnode_free_rcu(struct rcu_head *head)
if (size <= PAGE_SIZE)
kfree(tn);
else
free_pages((unsigned long)tn, get_order(size));
else {
INIT_WORK(&tn->work, __tnode_vfree);
schedule_work(&tn->work);
}
}
static inline void tnode_free(struct tnode *tn)