From 637c36634029e4e7c81112796dafc32d56355b4a Mon Sep 17 00:00:00 2001 From: Nadia Derbey Date: Thu, 18 Oct 2007 23:40:50 -0700 Subject: [PATCH] ipc: remove the ipc_get() routine This is a trivial patch that removes the ipc_get() routine: it is replaced by a call to idr_find(). Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/shm.c | 16 +++++++++++++--- ipc/util.c | 19 ------------------- ipc/util.h | 1 - 3 files changed, 13 insertions(+), 23 deletions(-) diff --git a/ipc/shm.c b/ipc/shm.c index d20cc25c5bd..8cf1cf3d5be 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -63,8 +63,6 @@ static struct ipc_ids init_shm_ids; ((struct shmid_kernel*)ipc_lock(&shm_ids(ns),id)) #define shm_unlock(shp) \ ipc_unlock(&(shp)->shm_perm) -#define shm_get(ns, id) \ - ((struct shmid_kernel*)ipc_get(&shm_ids(ns),id)) #define shm_buildid(ns, id, seq) \ ipc_buildid(&shm_ids(ns), id, seq) @@ -563,7 +561,19 @@ static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss, struct shmid_kernel *shp; struct inode *inode; - shp = shm_get(ns, next_id); + /* + * idr_find() is called via shm_get(), so with shm_ids.mutex + * locked. Since ipc_addid() is also called with + * shm_ids.mutex down, there is no need to add read barriers + * here to gurantee the writes in ipc_addid() are seen in + * order here (for Alpha). + * However idr_find() itself does not necessary require + * ipc_ids.mutex down. So if idr_find() is used by other + * places without ipc_ids.mutex down, then it needs read + * read memory barriers as ipc_lock() does. + */ + + shp = idr_find(&shm_ids(ns).ipcs_idr, next_id); if (shp == NULL) continue; diff --git a/ipc/util.c b/ipc/util.c index 03b88798f71..e72865f677a 100644 --- a/ipc/util.c +++ b/ipc/util.c @@ -669,25 +669,6 @@ void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out) out->seq = in->seq; } -/* - * So far only shm_get_stat() calls ipc_get() via shm_get(), so ipc_get() - * is called with shm_ids.mutex locked. Since grow_ary() is also called with - * shm_ids.mutex down(for Shared Memory), there is no need to add read - * barriers here to gurantee the writes in grow_ary() are seen in order - * here (for Alpha). - * - * However ipc_get() itself does not necessary require ipc_ids.mutex down. So - * if in the future ipc_get() is used by other places without ipc_ids.mutex - * down, then ipc_get() needs read memery barriers as ipc_lock() does. - */ -struct kern_ipc_perm *ipc_get(struct ipc_ids *ids, int id) -{ - struct kern_ipc_perm *out; - int lid = id % SEQ_MULTIPLIER; - out = idr_find(&ids->ipcs_idr, lid); - return out; -} - struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id) { struct kern_ipc_perm *out; diff --git a/ipc/util.h b/ipc/util.h index 30b2a6d7cbe..1546eda7d99 100644 --- a/ipc/util.h +++ b/ipc/util.h @@ -103,7 +103,6 @@ void* ipc_rcu_alloc(int size); void ipc_rcu_getref(void *ptr); void ipc_rcu_putref(void *ptr); -struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id); struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id); void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp); void ipc_unlock(struct kern_ipc_perm* perm); -- 2.41.1