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| author | Eric Dumazet <eric.dumazet@gmail.com> | 2009-11-12 09:33:09 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-11-13 20:46:58 -0800 |
| commit | 2c1409a0a2b88585ec0c03f1de0aafa178c56313 (patch) | |
| tree | e9fc25badfb716e5368079535f548cc8e4b5576a /include | |
| parent | 234b27c3fd58fc0e15c04dd0fbf4337fac9c2a06 (diff) | |
| download | linux-2c1409a0a2b88585ec0c03f1de0aafa178c56313.tar.gz | |
inetpeer: Optimize inet_getid()
While investigating for network latencies, I found inet_getid() was a contention point for some workloads, as inet_peer_idlock is shared by all inet_getid() users regardless of peers. One way to fix this is to make ip_id_count an atomic_t instead of __u16, and use atomic_add_return(). In order to keep sizeof(struct inet_peer) = 64 on 64bit arches tcp_ts_stamp is also converted to __u32 instead of "unsigned long". Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/inetpeer.h | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/include/net/inetpeer.h b/include/net/inetpeer.h index 35ad7b930467..87b1df0d4d8c 100644 --- a/include/net/inetpeer.h +++ b/include/net/inetpeer.h @@ -17,15 +17,15 @@ struct inet_peer { /* group together avl_left,avl_right,v4daddr to speedup lookups */ struct inet_peer *avl_left, *avl_right; __be32 v4daddr; /* peer's address */ - __u16 avl_height; - __u16 ip_id_count; /* IP ID for the next packet */ + __u32 avl_height; struct list_head unused; __u32 dtime; /* the time of last use of not * referenced entries */ atomic_t refcnt; atomic_t rid; /* Frag reception counter */ + atomic_t ip_id_count; /* IP ID for the next packet */ __u32 tcp_ts; - unsigned long tcp_ts_stamp; + __u32 tcp_ts_stamp; }; void inet_initpeers(void) __init; @@ -36,17 +36,11 @@ struct inet_peer *inet_getpeer(__be32 daddr, int create); /* can be called from BH context or outside */ extern void inet_putpeer(struct inet_peer *p); -extern spinlock_t inet_peer_idlock; /* can be called with or without local BH being disabled */ static inline __u16 inet_getid(struct inet_peer *p, int more) { - __u16 id; - - spin_lock_bh(&inet_peer_idlock); - id = p->ip_id_count; - p->ip_id_count += 1 + more; - spin_unlock_bh(&inet_peer_idlock); - return id; + more++; + return atomic_add_return(more, &p->ip_id_count) - more; } #endif /* _NET_INETPEER_H */ |