From 13ff3d6fa4e6d8b6ee7c64245a0078e6a0e6f977 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Fri, 28 Mar 2008 16:38:17 -0700 Subject: [SOCK]: Enumerate struct proto-s to facilitate percpu inuse accounting (v2). The inuse counters are going to become a per-cpu array. Introduce an index for this array on the struct proto. To handle the case of proto register-unregister-register loop the bitmap is used. All its bits manipulations are protected with proto_list_lock and a sanity check for the bitmap being exhausted is also added. Signed-off-by: Pavel Emelyanov Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/sock.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 3ee95060dbd..7d2c8add5f5 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1940,6 +1940,38 @@ EXPORT_SYMBOL(sk_common_release); static DEFINE_RWLOCK(proto_list_lock); static LIST_HEAD(proto_list); +#ifdef CONFIG_PROC_FS +#define PROTO_INUSE_NR 64 /* should be enough for the first time */ + +static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); + +static void assign_proto_idx(struct proto *prot) +{ + prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); + + if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { + printk(KERN_ERR "PROTO_INUSE_NR exhausted\n"); + return; + } + + set_bit(prot->inuse_idx, proto_inuse_idx); +} + +static void release_proto_idx(struct proto *prot) +{ + if (prot->inuse_idx != PROTO_INUSE_NR - 1) + clear_bit(prot->inuse_idx, proto_inuse_idx); +} +#else +static inline void assign_proto_idx(struct proto *prot) +{ +} + +static inline void release_proto_idx(struct proto *prot) +{ +} +#endif + int proto_register(struct proto *prot, int alloc_slab) { char *request_sock_slab_name = NULL; @@ -2000,6 +2032,7 @@ int proto_register(struct proto *prot, int alloc_slab) write_lock(&proto_list_lock); list_add(&prot->node, &proto_list); + assign_proto_idx(prot); write_unlock(&proto_list_lock); return 0; @@ -2026,6 +2059,7 @@ EXPORT_SYMBOL(proto_register); void proto_unregister(struct proto *prot) { write_lock(&proto_list_lock); + release_proto_idx(prot); list_del(&prot->node); write_unlock(&proto_list_lock); -- cgit v1.2.3