From df844fd46b98c2efde8f4ac2d50d59bc90c4c679 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 23 Aug 2016 15:27:24 +0100 Subject: rxrpc: Use a tracepoint for skb accounting debugging Use a tracepoint to log various skb accounting points to help in debugging refcounting errors. Signed-off-by: David Howells --- net/rxrpc/skbuff.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) (limited to 'net/rxrpc/skbuff.c') diff --git a/net/rxrpc/skbuff.c b/net/rxrpc/skbuff.c index 06c51d4b622d..d28058a97bc1 100644 --- a/net/rxrpc/skbuff.c +++ b/net/rxrpc/skbuff.c @@ -163,3 +163,65 @@ void rxrpc_kernel_free_skb(struct sk_buff *skb) rxrpc_free_skb(skb); } EXPORT_SYMBOL(rxrpc_kernel_free_skb); + +/* + * Note the existence of a new-to-us socket buffer (allocated or dequeued). + */ +void rxrpc_new_skb(struct sk_buff *skb) +{ + const void *here = __builtin_return_address(0); + int n = atomic_inc_return(&rxrpc_n_skbs); + trace_rxrpc_skb(skb, 0, atomic_read(&skb->users), n, here); +} + +/* + * Note the re-emergence of a socket buffer from a queue or buffer. + */ +void rxrpc_see_skb(struct sk_buff *skb) +{ + const void *here = __builtin_return_address(0); + if (skb) { + int n = atomic_read(&rxrpc_n_skbs); + trace_rxrpc_skb(skb, 1, atomic_read(&skb->users), n, here); + } +} + +/* + * Note the addition of a ref on a socket buffer. + */ +void rxrpc_get_skb(struct sk_buff *skb) +{ + const void *here = __builtin_return_address(0); + int n = atomic_inc_return(&rxrpc_n_skbs); + trace_rxrpc_skb(skb, 2, atomic_read(&skb->users), n, here); + skb_get(skb); +} + +/* + * Note the destruction of a socket buffer. + */ +void rxrpc_free_skb(struct sk_buff *skb) +{ + const void *here = __builtin_return_address(0); + if (skb) { + int n; + CHECK_SLAB_OKAY(&skb->users); + n = atomic_dec_return(&rxrpc_n_skbs); + trace_rxrpc_skb(skb, 3, atomic_read(&skb->users), n, here); + kfree_skb(skb); + } +} + +/* + * Clear a queue of socket buffers. + */ +void rxrpc_purge_queue(struct sk_buff_head *list) +{ + const void *here = __builtin_return_address(0); + struct sk_buff *skb; + while ((skb = skb_dequeue((list))) != NULL) { + int n = atomic_dec_return(&rxrpc_n_skbs); + trace_rxrpc_skb(skb, 4, atomic_read(&skb->users), n, here); + kfree_skb(skb); + } +} -- cgit v1.2.1