From: Greg Banks Convert the svc_sock->sk_reserved variable from an int protected by svc_serv->sv_lock, to an atomic. This reduces (by 1) the number of places we need to take the (effectively global) svc_serv->sv_lock. Signed-off-by: Greg Banks Signed-off-by: Neil Brown Signed-off-by: Andrew Morton --- include/linux/sunrpc/svcsock.h | 2 +- net/sunrpc/svcsock.c | 12 +++++------- 2 files changed, 6 insertions(+), 8 deletions(-) diff -puN include/linux/sunrpc/svcsock.h~knfsd-convert-sk_reserved-to-atomic_t include/linux/sunrpc/svcsock.h --- a/include/linux/sunrpc/svcsock.h~knfsd-convert-sk_reserved-to-atomic_t +++ a/include/linux/sunrpc/svcsock.h @@ -34,7 +34,7 @@ struct svc_sock { #define SK_OLD 9 /* used for temp socket aging mark+sweep */ #define SK_DETACHED 10 /* detached from tempsocks list */ - int sk_reserved; /* space on outq that is reserved */ + atomic_t sk_reserved; /* space on outq that is reserved */ spinlock_t sk_defer_lock; /* protects sk_deferred */ struct list_head sk_deferred; /* deferred requests that need to diff -puN net/sunrpc/svcsock.c~knfsd-convert-sk_reserved-to-atomic_t net/sunrpc/svcsock.c --- a/net/sunrpc/svcsock.c~knfsd-convert-sk_reserved-to-atomic_t +++ a/net/sunrpc/svcsock.c @@ -177,13 +177,13 @@ svc_sock_enqueue(struct svc_sock *svsk) } set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); - if (((svsk->sk_reserved + serv->sv_bufsz)*2 + if (((atomic_read(&svsk->sk_reserved) + serv->sv_bufsz)*2 > svc_sock_wspace(svsk)) && !test_bit(SK_CLOSE, &svsk->sk_flags) && !test_bit(SK_CONN, &svsk->sk_flags)) { /* Don't enqueue while not enough space for reply */ dprintk("svc: socket %p no space, %d*2 > %ld, not enqueued\n", - svsk->sk_sk, svsk->sk_reserved+serv->sv_bufsz, + svsk->sk_sk, atomic_read(&svsk->sk_reserved)+serv->sv_bufsz, svc_sock_wspace(svsk)); goto out_unlock; } @@ -209,7 +209,7 @@ svc_sock_enqueue(struct svc_sock *svsk) rqstp->rq_sock = svsk; atomic_inc(&svsk->sk_inuse); rqstp->rq_reserved = serv->sv_bufsz; - svsk->sk_reserved += rqstp->rq_reserved; + atomic_add(rqstp->rq_reserved, &svsk->sk_reserved); wake_up(&rqstp->rq_wait); } else { dprintk("svc: socket %p put into queue\n", svsk->sk_sk); @@ -271,10 +271,8 @@ void svc_reserve(struct svc_rqst *rqstp, if (space < rqstp->rq_reserved) { struct svc_sock *svsk = rqstp->rq_sock; - spin_lock_bh(&svsk->sk_server->sv_lock); - svsk->sk_reserved -= (rqstp->rq_reserved - space); + atomic_sub((rqstp->rq_reserved - space), &svsk->sk_reserved); rqstp->rq_reserved = space; - spin_unlock_bh(&svsk->sk_server->sv_lock); svc_sock_enqueue(svsk); } @@ -1236,7 +1234,7 @@ svc_recv(struct svc_rqst *rqstp, long ti rqstp->rq_sock = svsk; atomic_inc(&svsk->sk_inuse); rqstp->rq_reserved = serv->sv_bufsz; - svsk->sk_reserved += rqstp->rq_reserved; + atomic_add(rqstp->rq_reserved, &svsk->sk_reserved); } else { /* No data pending. Go to sleep */ svc_serv_enqueue(serv, rqstp); _