diff options
Diffstat (limited to 'include/net/sock.h')
| -rw-r--r-- | include/net/sock.h | 63 |
1 files changed, 57 insertions, 6 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 20de3fa7ae40..5504fb9fa88a 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -560,6 +560,14 @@ struct proto { void (*unhash)(struct sock *sk); int (*get_port)(struct sock *sk, unsigned short snum); +#ifdef CONFIG_SMP + /* Keeping track of sockets in use */ + void (*inuse_add)(struct proto *prot, int inc); + int (*inuse_getval)(const struct proto *prot); + int *inuse_ptr; +#else + int inuse; +#endif /* Memory pressure */ void (*enter_memory_pressure)(void); atomic_t *memory_allocated; /* Current allocated memory. */ @@ -592,12 +600,38 @@ struct proto { #ifdef SOCK_REFCNT_DEBUG atomic_t socks; #endif - struct { - int inuse; - u8 __pad[SMP_CACHE_BYTES - sizeof(int)]; - } stats[NR_CPUS]; }; +/* + * Special macros to let protos use a fast version of inuse{get|add} + * using a static percpu variable per proto instead of an allocated one, + * saving one dereference. + * This might be changed if/when dynamic percpu vars become fast. + */ +#ifdef CONFIG_SMP +# define DEFINE_PROTO_INUSE(NAME) \ +static DEFINE_PER_CPU(int, NAME##_inuse); \ +static void NAME##_inuse_add(struct proto *prot, int inc) \ +{ \ + __get_cpu_var(NAME##_inuse) += inc; \ +} \ + \ +static int NAME##_inuse_getval(const struct proto *prot)\ +{ \ + int res = 0, cpu; \ + \ + for_each_possible_cpu(cpu) \ + res += per_cpu(NAME##_inuse, cpu); \ + return res; \ +} +# define REF_PROTO_INUSE(NAME) \ + .inuse_add = NAME##_inuse_add, \ + .inuse_getval = NAME##_inuse_getval, +#else +# define DEFINE_PROTO_INUSE(NAME) +# define REF_PROTO_INUSE(NAME) +#endif + extern int proto_register(struct proto *prot, int alloc_slab); extern void proto_unregister(struct proto *prot); @@ -629,12 +663,29 @@ static inline void sk_refcnt_debug_release(const struct sock *sk) /* Called with local bh disabled */ static __inline__ void sock_prot_inc_use(struct proto *prot) { - prot->stats[smp_processor_id()].inuse++; +#ifdef CONFIG_SMP + prot->inuse_add(prot, 1); +#else + prot->inuse++; +#endif } static __inline__ void sock_prot_dec_use(struct proto *prot) { - prot->stats[smp_processor_id()].inuse--; +#ifdef CONFIG_SMP + prot->inuse_add(prot, -1); +#else + prot->inuse--; +#endif +} + +static __inline__ int sock_prot_inuse(struct proto *proto) +{ +#ifdef CONFIG_SMP + return proto->inuse_getval(proto); +#else + return proto->inuse; +#endif } /* With per-bucket locks this operation is not-atomic, so that |