mm: always print RLIMIT_DATA warning

The documentation for ignore_rlimit_data says that it will print a
warning at first misuse.  Yet it doesn't seem to do that.

Fix the code to print the warning even when we allow the process to
continue.

Link: http://lkml.kernel.org/r/1517935505-9321-1-git-send-email-dwmw@amazon.co.ukSigned-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/mmap.c

@@ -3191,14 +3191,16 @@ bool may_expand_vm(struct mm_struct *mm, vm_flags_t flags, unsigned long npages)
 		if (rlimit(RLIMIT_DATA) == 0 &&
 		    mm->data_vm + npages <= rlimit_max(RLIMIT_DATA) >> PAGE_SHIFT)
 			return true;
-		if (!ignore_rlimit_data) {
-			pr_warn_once("%s (%d): VmData %lu exceed data ulimit %lu. Update limits or use boot option ignore_rlimit_data.\n",
+
+		pr_warn_once("%s (%d): VmData %lu exceed data ulimit %lu. Update limits%s.\n",
 			     current->comm, current->pid,
 			     (mm->data_vm + npages) << PAGE_SHIFT,
-				     rlimit(RLIMIT_DATA));
+			     rlimit(RLIMIT_DATA),
+			     ignore_rlimit_data ? "" : " or use boot option ignore_rlimit_data");
+
+		if (!ignore_rlimit_data)
 			return false;
 	}
-	}
 
 	return true;
 }