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| author | Robert Olsson <robert.olsson@its.uu.se> | 2009-05-21 15:20:59 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-05-21 15:20:59 -0700 |
| commit | 3ed18d76d959e5cbfa5d70c8f7ba95476582a556 (patch) | |
| tree | 9fbd15b820b43627440fd6961f687c30e8d4e130 /net | |
| parent | 5b5f792a6a9a2f9ae812d151ed621f72e99b1725 (diff) | |
| download | lwn-3ed18d76d959e5cbfa5d70c8f7ba95476582a556.tar.gz lwn-3ed18d76d959e5cbfa5d70c8f7ba95476582a556.zip | |
ipv4: Fix oops with FIB_TRIE
It seems we can fix this by disabling preemption while we re-balance the
trie. This is with the CONFIG_CLASSIC_RCU. It's been stress-tested at high
loads continuesly taking a full BGP table up/down via iproute -batch.
Note. fib_trie is not updated for CONFIG_PREEMPT_RCU
Reported-by: Andrei Popa
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/fib_trie.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index ec0ae490f0b6..33c7c85dfe40 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -986,9 +986,12 @@ fib_find_node(struct trie *t, u32 key) static struct node *trie_rebalance(struct trie *t, struct tnode *tn) { int wasfull; - t_key cindex, key = tn->key; + t_key cindex, key; struct tnode *tp; + preempt_disable(); + key = tn->key; + while (tn != NULL && (tp = node_parent((struct node *)tn)) != NULL) { cindex = tkey_extract_bits(key, tp->pos, tp->bits); wasfull = tnode_full(tp, tnode_get_child(tp, cindex)); @@ -1007,6 +1010,7 @@ static struct node *trie_rebalance(struct trie *t, struct tnode *tn) if (IS_TNODE(tn)) tn = (struct tnode *)resize(t, (struct tnode *)tn); + preempt_enable(); return (struct node *)tn; } |