3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> commit 1a24e04e4b50939daa3041682b38b82c896ca438 upstream. sk_mem_reclaim_partial() goal is to ensure each socket has one SK_MEM_QUANTUM forward allocation. This is needed both for performance and better handling of memory pressure situations in follow up patches. SK_MEM_QUANTUM is currently a page, but might be reduced to 4096 bytes as some arches have 64KB pages. Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- include/net/sock.h | 6 +++--- net/core/sock.c | 9 +++++---- 2 files changed, 8 insertions(+), 7 deletions(-) --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1411,7 +1411,7 @@ static inline struct inode *SOCK_INODE(s * Functions for memory accounting */ int __sk_mem_schedule(struct sock *sk, int size, int kind); -void __sk_mem_reclaim(struct sock *sk); +void __sk_mem_reclaim(struct sock *sk, int amount); #define SK_MEM_QUANTUM ((int)PAGE_SIZE) #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) @@ -1452,7 +1452,7 @@ static inline void sk_mem_reclaim(struct if (!sk_has_account(sk)) return; if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) - __sk_mem_reclaim(sk); + __sk_mem_reclaim(sk, sk->sk_forward_alloc); } static inline void sk_mem_reclaim_partial(struct sock *sk) @@ -1460,7 +1460,7 @@ static inline void sk_mem_reclaim_partia if (!sk_has_account(sk)) return; if (sk->sk_forward_alloc > SK_MEM_QUANTUM) - __sk_mem_reclaim(sk); + __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); } static inline void sk_mem_charge(struct sock *sk, int size) --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2125,12 +2125,13 @@ EXPORT_SYMBOL(__sk_mem_schedule); /** * __sk_reclaim - reclaim memory_allocated * @sk: socket + * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) */ -void __sk_mem_reclaim(struct sock *sk) +void __sk_mem_reclaim(struct sock *sk, int amount) { - sk_memory_allocated_sub(sk, - sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); - sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; + amount >>= SK_MEM_QUANTUM_SHIFT; + sk_memory_allocated_sub(sk, amount); + sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; if (sk_under_memory_pressure(sk) && (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))