Basic sock operations that udp code can use with its own
memory accounting schema. No functional change is introduced
in the existing APIs.
Acked-by: Hannes Frederic Sowa <han...@stressinduktion.org>
Signed-off-by: Paolo Abeni <pab...@redhat.com>
---
include/linux/skbuff.h | 2 +-
include/net/sock.h | 5 +++
net/core/datagram.c | 36 +++++++++++--------
net/core/skbuff.c | 3 +-
net/core/sock.c | 96 +++++++++++++++++++++++++++++++++-----------------
5 files changed, 94 insertions(+), 48 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index cfb7219..49c489d 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3016,7 +3016,7 @@ static inline void skb_frag_list_init(struct sk_buff *skb)
#define skb_walk_frags(skb, iter) \
for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
-
+void sock_rmem_free(struct sk_buff *skb);
int __skb_wait_for_more_packets(struct sock *sk, int *err, long *timeo_p,
const struct sk_buff *skb);
struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned flags,
diff --git a/include/net/sock.h b/include/net/sock.h
index c797c57..a37362c 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1274,7 +1274,9 @@ static inline struct inode *SOCK_INODE(struct socket
*socket)
/*
* Functions for memory accounting
*/
+int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
int __sk_mem_schedule(struct sock *sk, int size, int kind);
+void __sk_mem_reduce_allocated(struct sock *sk, int amount);
void __sk_mem_reclaim(struct sock *sk, int amount);
#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
@@ -1940,6 +1942,9 @@ void sk_reset_timer(struct sock *sk, struct timer_list
*timer,
void sk_stop_timer(struct sock *sk, struct timer_list *timer);
+int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb,
+ unsigned int flags);
+void __sock_enqueue_skb(struct sock *sk, struct sk_buff *skb);
int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
diff --git a/net/core/datagram.c b/net/core/datagram.c
index b7de71f..bfb973a 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -323,6 +323,27 @@ void __skb_free_datagram_locked(struct sock *sk, struct
sk_buff *skb, int len)
}
EXPORT_SYMBOL(__skb_free_datagram_locked);
+int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb,
+ unsigned int flags)
+{
+ int err = 0;
+
+ if (flags & MSG_PEEK) {
+ err = -ENOENT;
+ spin_lock_bh(&sk->sk_receive_queue.lock);
+ if (skb == skb_peek(&sk->sk_receive_queue)) {
+ __skb_unlink(skb, &sk->sk_receive_queue);
+ atomic_dec(&skb->users);
+ err = 0;
+ }
+ spin_unlock_bh(&sk->sk_receive_queue.lock);
+ }
+
+ atomic_inc(&sk->sk_drops);
+ return err;
+}
+EXPORT_SYMBOL(__sk_queue_drop_skb);
+
/**
* skb_kill_datagram - Free a datagram skbuff forcibly
* @sk: socket
@@ -346,23 +367,10 @@ EXPORT_SYMBOL(__skb_free_datagram_locked);
int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags)
{
- int err = 0;
-
- if (flags & MSG_PEEK) {
- err = -ENOENT;
- spin_lock_bh(&sk->sk_receive_queue.lock);
- if (skb == skb_peek(&sk->sk_receive_queue)) {
- __skb_unlink(skb, &sk->sk_receive_queue);
- atomic_dec(&skb->users);
- err = 0;
- }
- spin_unlock_bh(&sk->sk_receive_queue.lock);
- }
+ int err = __sk_queue_drop_skb(sk, skb, flags);
kfree_skb(skb);
- atomic_inc(&sk->sk_drops);
sk_mem_reclaim_partial(sk);
-
return err;
}
EXPORT_SYMBOL(skb_kill_datagram);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 3864b4b6..4dce605 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3657,12 +3657,13 @@ int skb_cow_data(struct sk_buff *skb, int tailbits,
struct sk_buff **trailer)
}
EXPORT_SYMBOL_GPL(skb_cow_data);
-static void sock_rmem_free(struct sk_buff *skb)
+void sock_rmem_free(struct sk_buff *skb)
{
struct sock *sk = skb->sk;
atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
}
+EXPORT_SYMBOL_GPL(sock_rmem_free);
/*
* Note: We dont mem charge error packets (no sk_forward_alloc changes)
diff --git a/net/core/sock.c b/net/core/sock.c
index 51a7304..752308d 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -405,24 +405,12 @@ static void sock_disable_timestamp(struct sock *sk,
unsigned long flags)
}
-int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+void __sock_enqueue_skb(struct sock *sk, struct sk_buff *skb)
{
unsigned long flags;
struct sk_buff_head *list = &sk->sk_receive_queue;
- if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
- atomic_inc(&sk->sk_drops);
- trace_sock_rcvqueue_full(sk, skb);
- return -ENOMEM;
- }
-
- if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
- atomic_inc(&sk->sk_drops);
- return -ENOBUFS;
- }
-
skb->dev = NULL;
- skb_set_owner_r(skb, sk);
/* we escape from rcu protected region, make sure we dont leak
* a norefcounted dst
@@ -436,6 +424,24 @@ int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff
*skb)
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_data_ready(sk);
+}
+EXPORT_SYMBOL(__sock_enqueue_skb);
+
+int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+ if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
+ atomic_inc(&sk->sk_drops);
+ trace_sock_rcvqueue_full(sk, skb);
+ return -ENOMEM;
+ }
+
+ if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
+ atomic_inc(&sk->sk_drops);
+ return -ENOBUFS;
+ }
+
+ skb_set_owner_r(skb, sk);
+ __sock_enqueue_skb(sk, skb);
return 0;
}
EXPORT_SYMBOL(__sock_queue_rcv_skb);
@@ -2088,24 +2094,18 @@ int sk_wait_data(struct sock *sk, long *timeo, const
struct sk_buff *skb)
EXPORT_SYMBOL(sk_wait_data);
/**
- * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
+ * __sk_mem_raise_allocated - increase memory_allocated
* @sk: socket
* @size: memory size to allocate
+ * @amt: pages to allocate
* @kind: allocation type
*
- * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
- * rmem allocation. This function assumes that protocols which have
- * memory_pressure use sk_wmem_queued as write buffer accounting.
+ * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
*/
-int __sk_mem_schedule(struct sock *sk, int size, int kind)
+int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
{
struct proto *prot = sk->sk_prot;
- int amt = sk_mem_pages(size);
- long allocated;
-
- sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
-
- allocated = sk_memory_allocated_add(sk, amt);
+ long allocated = sk_memory_allocated_add(sk, amt);
if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
!mem_cgroup_charge_skmem(sk->sk_memcg, amt))
@@ -2166,9 +2166,6 @@ suppress_allocation:
trace_sock_exceed_buf_limit(sk, prot, allocated);
- /* Alas. Undo changes. */
- sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
-
sk_memory_allocated_sub(sk, amt);
if (mem_cgroup_sockets_enabled && sk->sk_memcg)
@@ -2176,18 +2173,40 @@ suppress_allocation:
return 0;
}
+EXPORT_SYMBOL(__sk_mem_raise_allocated);
+
+/**
+ * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
+ * @sk: socket
+ * @size: memory size to allocate
+ * @kind: allocation type
+ *
+ * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
+ * rmem allocation. This function assumes that protocols which have
+ * memory_pressure use sk_wmem_queued as write buffer accounting.
+ */
+int __sk_mem_schedule(struct sock *sk, int size, int kind)
+{
+ int ret, amt = sk_mem_pages(size);
+
+ sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
+ ret = __sk_mem_raise_allocated(sk, size, amt, kind);
+ if (!ret)
+ sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
+ return ret;
+}
EXPORT_SYMBOL(__sk_mem_schedule);
/**
- * __sk_mem_reclaim - reclaim memory_allocated
+ * __sk_mem_reduce_allocated - reclaim memory_allocated
* @sk: socket
- * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
+ * @amount: number of quanta
+ *
+ * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
*/
-void __sk_mem_reclaim(struct sock *sk, int amount)
+void __sk_mem_reduce_allocated(struct sock *sk, int amount)
{
- amount >>= SK_MEM_QUANTUM_SHIFT;
sk_memory_allocated_sub(sk, amount);
- sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
if (mem_cgroup_sockets_enabled && sk->sk_memcg)
mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
@@ -2196,6 +2215,19 @@ void __sk_mem_reclaim(struct sock *sk, int amount)
(sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
sk_leave_memory_pressure(sk);
}
+EXPORT_SYMBOL(__sk_mem_reduce_allocated);
+
+/**
+ * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
+ * @sk: socket
+ * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
+ */
+void __sk_mem_reclaim(struct sock *sk, int amount)
+{
+ amount >>= SK_MEM_QUANTUM_SHIFT;
+ sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
+ __sk_mem_reduce_allocated(sk, amount);
+}
EXPORT_SYMBOL(__sk_mem_reclaim);
int sk_set_peek_off(struct sock *sk, int val)
--
1.8.3.1
