From f8c3bf00d440df2bc2c3f669d460868d9ba67226 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 21 Oct 2016 13:55:45 +0200 Subject: [PATCH] net/socket: factor out helpers for memory and queue manipulation Basic sock operations that udp code can use with its own memory accounting schema. No functional change is introduced in the existing APIs. v4 -> v5: - avoid whitespace changes v2 -> v4: - avoid exporting __sock_enqueue_skb v1 -> v2: - avoid export sock_rmem_free Acked-by: Hannes Frederic Sowa Signed-off-by: Paolo Abeni Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/sock.h | 4 ++++ net/core/datagram.c | 36 ++++++++++++++++++------------ net/core/sock.c | 64 +++++++++++++++++++++++++++++++++++++---------------- 3 files changed, 71 insertions(+), 33 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index ebf75db..2764895 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) @@ -1950,6 +1952,8 @@ 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); 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/sock.c b/net/core/sock.c index c73e28f..d8e4532e 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2091,24 +2091,18 @@ 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)) @@ -2169,9 +2163,6 @@ 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) @@ -2179,18 +2170,40 @@ 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); @@ -2199,6 +2212,19 @@ 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) -- 2.7.4