ipc: refactor msg list search into separate function
Peter Hurley [Wed, 1 May 2013 02:15:04 +0000 (19:15 -0700)]
[fengguang.wu@intel.com: find_msg can be static]
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/msg.c

index a922750..a80aaf4 100644 (file)
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -807,6 +807,30 @@ static inline void free_copy(struct msg_msg *copy)
 }
 #endif
 
+static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode)
+{
+       struct msg_msg *msg;
+       long count = 0;
+
+       list_for_each_entry(msg, &msq->q_messages, m_list) {
+               if (testmsg(msg, *msgtyp, mode) &&
+                   !security_msg_queue_msgrcv(msq, msg, current,
+                                              *msgtyp, mode)) {
+                       if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) {
+                               *msgtyp = msg->m_type - 1;
+                       } else if (mode == SEARCH_NUMBER) {
+                               if (*msgtyp == count)
+                                       return msg;
+                       } else
+                               return msg;
+                       count++;
+               }
+       }
+
+       return ERR_PTR(-EAGAIN);
+}
+
+
 long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp,
               int msgflg,
               long (*msg_handler)(void __user *, struct msg_msg *, size_t))
@@ -836,33 +860,13 @@ long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp,
 
        for (;;) {
                struct msg_receiver msr_d;
-               struct msg_msg *walk_msg;
-               long msg_counter = 0;
 
                msg = ERR_PTR(-EACCES);
                if (ipcperms(ns, &msq->q_perm, S_IRUGO))
                        goto out_unlock;
 
-               msg = ERR_PTR(-EAGAIN);
-               list_for_each_entry(walk_msg, &msq->q_messages, m_list) {
-
-                       if (testmsg(walk_msg, msgtyp, mode) &&
-                           !security_msg_queue_msgrcv(msq, walk_msg, current,
-                                                      msgtyp, mode)) {
-
-                               msg = walk_msg;
-                               if (mode == SEARCH_LESSEQUAL &&
-                                               walk_msg->m_type != 1) {
-                                       msgtyp = walk_msg->m_type - 1;
-                               } else if (mode == SEARCH_NUMBER) {
-                                       if (msgtyp == msg_counter)
-                                               break;
-                                       msg = ERR_PTR(-EAGAIN);
-                               } else
-                                       break;
-                               msg_counter++;
-                       }
-               }
+               msg = find_msg(msq, &msgtyp, mode);
+
                if (!IS_ERR(msg)) {
                        /*
                         * Found a suitable message.