[PATCH 07/12] ipc_idr_alloc refactoring

[Manfred Spraul]

From: Dmitry Vyukov <dvyu...@google.com>

ipc_idr_alloc refactoring

Signed-off-by: Dmitry Vyukov <dvyu...@google.com>
Signed-off-by: Manfred Spraul <manf...@colorfullife.com>
---
 ipc/util.c | 51 +++++++++++++--------------------------------------
 1 file changed, 13 insertions(+), 38 deletions(-)

diff --git a/ipc/util.c b/ipc/util.c
index 8bc166bb4981..a41b8a69de13 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -193,52 +193,32 @@ static struct kern_ipc_perm *ipc_findkey(struct ipc_ids 
*ids, key_t key)
        return NULL;
 }
 
-#ifdef CONFIG_CHECKPOINT_RESTORE
 /*
  * Specify desired id for next allocated IPC object.
  */
-static inline int ipc_idr_alloc(struct ipc_ids *ids,
-                               struct kern_ipc_perm *new)
+static inline int ipc_idr_alloc(struct ipc_ids *ids, struct kern_ipc_perm *new)
 {
-       int key;
+       int key, next_id = -1;
 
-       if (ids->next_id < 0) {
-               key = idr_alloc(&ids->ipcs_idr, new, 0, 0, GFP_NOWAIT);
-       } else {
-               key = idr_alloc(&ids->ipcs_idr, new,
-                               ipcid_to_idx(ids->next_id),
-                               0, GFP_NOWAIT);
-               ids->next_id = -1;
-       }
-       return key;
-}
+#ifdef CONFIG_CHECKPOINT_RESTORE
+       next_id = ids->next_id;
+       ids->next_id = -1;
+#endif
 
-static inline void ipc_set_seq(struct ipc_ids *ids,
-                               struct kern_ipc_perm *new)
-{
-       if (ids->next_id < 0) { /* default, behave as !CHECKPOINT_RESTORE */
+       if (next_id < 0) { /* !CHECKPOINT_RESTORE or next_id is unset */
                new->seq = ids->seq++;
                if (ids->seq > IPCID_SEQ_MAX)
                        ids->seq = 0;
+               key = idr_alloc(&ids->ipcs_idr, new, 0, 0, GFP_NOWAIT);
        } else {
-               new->seq = ipcid_to_seqx(ids->next_id);
+               new->seq = ipcid_to_seqx(next_id);
+               key = idr_alloc(&ids->ipcs_idr, new, ipcid_to_idx(next_id),
+                               0, GFP_NOWAIT);
        }
+       new->id = SEQ_MULTIPLIER * new->seq + key;
+       return key;
 }
 
-#else
-#define ipc_idr_alloc(ids, new)                                        \
-       idr_alloc(&(ids)->ipcs_idr, (new), 0, 0, GFP_NOWAIT)
-
-static inline void ipc_set_seq(struct ipc_ids *ids,
-                             struct kern_ipc_perm *new)
-{
-       new->seq = ids->seq++;
-       if (ids->seq > IPCID_SEQ_MAX)
-               ids->seq = 0;
-}
-
-#endif /* CONFIG_CHECKPOINT_RESTORE */
-
 /**
  * ipc_addid - add an ipc identifier
  * @ids: ipc identifier set
@@ -278,8 +258,6 @@ int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm 
*new, int limit)
        current_euid_egid(&euid, &egid);
        new->cuid = new->uid = euid;
        new->gid = new->cgid = egid;
-
-       ipc_set_seq(ids, new);
        new->deleted = false;
 
        /*
@@ -317,9 +295,6 @@ int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm 
*new, int limit)
        ids->in_use++;
        if (id > ids->max_id)
                ids->max_id = id;
-
-       new->id = SEQ_MULTIPLIER * new->seq + id;
-
        return id;
 }
 
-- 
2.17.1