[PATCH 03/06] 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 --- ipc/shm.c | 16 +++++++++++++--- ipc/util.c | 19 ------------------- ipc/util.h | 1 - 3 files changed, 13 insertions(+), 23 deletions(-) Index: linux-2.6.23-rc2/ipc/util.h =================================================================== --- linux-2.6.23-rc2.orig/ipc/util.h 2007-08-31 11:38:50.000000000 +0200 +++ linux-2.6.23-rc2/ipc/util.h 2007-08-31 11:59:11.000000000 +0200 @@ -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); Index: linux-2.6.23-rc2/ipc/util.c =================================================================== --- linux-2.6.23-rc2.orig/ipc/util.c 2007-08-31 11:40:03.000000000 +0200 +++ linux-2.6.23-rc2/ipc/util.c 2007-08-31 11:59:46.000000000 +0200 @@ -669,25 +669,6 @@ void ipc64_perm_to_ipc_perm (struct ipc6 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; Index: linux-2.6.23-rc2/ipc/shm.c =================================================================== --- linux-2.6.23-rc2.orig/ipc/shm.c 2007-08-31 11:45:57.000000000 +0200 +++ linux-2.6.23-rc2/ipc/shm.c 2007-08-31 12:13:27.000000000 +0200 @@ -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) @@ -562,7 +560,19 @@ static void shm_get_stat(struct ipc_name 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; -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/