From 6ff3797218ef41c248c83184101ce1aedc227333 Mon Sep 17 00:00:00 2001 From: Pierre Peiffer Date: Tue, 29 Apr 2008 01:00:46 -0700 Subject: IPC/semaphores: code factorisation Trivial patch which adds some small locking functions and makes use of them to factorize some part of the code and to make it cleaner. Signed-off-by: Pierre Peiffer Acked-by: Serge Hallyn Cc: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/sem.c | 61 +++++++++++++++++++++++++++++++------------------------------ 1 file changed, 31 insertions(+), 30 deletions(-) (limited to 'ipc/sem.c') diff --git a/ipc/sem.c b/ipc/sem.c index 08da8648925..1b5ae352cde 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -180,6 +180,25 @@ static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, return container_of(ipcp, struct sem_array, sem_perm); } +static inline void sem_lock_and_putref(struct sem_array *sma) +{ + ipc_lock_by_ptr(&sma->sem_perm); + ipc_rcu_putref(sma); +} + +static inline void sem_getref_and_unlock(struct sem_array *sma) +{ + ipc_rcu_getref(sma); + ipc_unlock(&(sma)->sem_perm); +} + +static inline void sem_putref(struct sem_array *sma) +{ + ipc_lock_by_ptr(&sma->sem_perm); + ipc_rcu_putref(sma); + ipc_unlock(&(sma)->sem_perm); +} + static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) { ipc_rmid(&sem_ids(ns), &s->sem_perm); @@ -698,19 +717,15 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; if(nsems > SEMMSL_FAST) { - ipc_rcu_getref(sma); - sem_unlock(sma); + sem_getref_and_unlock(sma); sem_io = ipc_alloc(sizeof(ushort)*nsems); if(sem_io == NULL) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - sem_unlock(sma); + sem_putref(sma); return -ENOMEM; } - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); + sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { sem_unlock(sma); err = -EIDRM; @@ -731,38 +746,30 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); - sem_unlock(sma); + sem_getref_and_unlock(sma); if(nsems > SEMMSL_FAST) { sem_io = ipc_alloc(sizeof(ushort)*nsems); if(sem_io == NULL) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - sem_unlock(sma); + sem_putref(sma); return -ENOMEM; } } if (copy_from_user (sem_io, arg.array, nsems*sizeof(ushort))) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - sem_unlock(sma); + sem_putref(sma); err = -EFAULT; goto out_free; } for (i = 0; i < nsems; i++) { if (sem_io[i] > SEMVMX) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - sem_unlock(sma); + sem_putref(sma); err = -ERANGE; goto out_free; } } - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); + sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { sem_unlock(sma); err = -EIDRM; @@ -1042,14 +1049,11 @@ static struct sem_undo *find_undo(struct ipc_namespace *ns, int semid) return ERR_PTR(PTR_ERR(sma)); nsems = sma->sem_nsems; - ipc_rcu_getref(sma); - sem_unlock(sma); + sem_getref_and_unlock(sma); new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL); if (!new) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - sem_unlock(sma); + sem_putref(sma); return ERR_PTR(-ENOMEM); } new->semadj = (short *) &new[1]; @@ -1060,13 +1064,10 @@ static struct sem_undo *find_undo(struct ipc_namespace *ns, int semid) if (un) { spin_unlock(&ulp->lock); kfree(new); - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - sem_unlock(sma); + sem_putref(sma); goto out; } - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); + sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { sem_unlock(sma); spin_unlock(&ulp->lock); -- cgit v1.2.3