xref: /linux/net/rxrpc/skbuff.c (revision 9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Socket buffer accounting
3  *
4  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/module.h>
11 #include <linux/net.h>
12 #include <linux/skbuff.h>
13 #include <net/sock.h>
14 #include <net/af_rxrpc.h>
15 #include "ar-internal.h"
16 
17 #define select_skb_count(skb) (&rxrpc_n_rx_skbs)
18 
19 /*
20  * Note the allocation or reception of a socket buffer.
21  */
rxrpc_new_skb(struct sk_buff * skb,enum rxrpc_skb_trace why)22 void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
23 {
24 	int n = atomic_inc_return(select_skb_count(skb));
25 	trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
26 }
27 
28 /*
29  * Note the re-emergence of a socket buffer from a queue or buffer.
30  */
rxrpc_see_skb(struct sk_buff * skb,enum rxrpc_skb_trace why)31 void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
32 {
33 	if (skb) {
34 		int n = atomic_read(select_skb_count(skb));
35 		trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
36 	}
37 }
38 
39 /*
40  * Note the addition of a ref on a socket buffer.
41  */
rxrpc_get_skb(struct sk_buff * skb,enum rxrpc_skb_trace why)42 void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
43 {
44 	int n = atomic_inc_return(select_skb_count(skb));
45 	trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
46 	skb_get(skb);
47 }
48 
49 /*
50  * Note the dropping of a ref on a socket buffer by the core.
51  */
rxrpc_eaten_skb(struct sk_buff * skb,enum rxrpc_skb_trace why)52 void rxrpc_eaten_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
53 {
54 	int n = atomic_inc_return(&rxrpc_n_rx_skbs);
55 	trace_rxrpc_skb(skb, 0, n, why);
56 }
57 
58 /*
59  * Note the destruction of a socket buffer.
60  */
rxrpc_free_skb(struct sk_buff * skb,enum rxrpc_skb_trace why)61 void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
62 {
63 	if (skb) {
64 		int n = atomic_dec_return(select_skb_count(skb));
65 		trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
66 		consume_skb(skb);
67 	}
68 }
69 
70 /*
71  * Clear a queue of socket buffers.
72  */
rxrpc_purge_queue(struct sk_buff_head * list)73 void rxrpc_purge_queue(struct sk_buff_head *list)
74 {
75 	struct sk_buff *skb;
76 
77 	while ((skb = skb_dequeue((list))) != NULL) {
78 		int n = atomic_dec_return(select_skb_count(skb));
79 		trace_rxrpc_skb(skb, refcount_read(&skb->users), n,
80 				rxrpc_skb_put_purge);
81 		consume_skb(skb);
82 	}
83 }
84