Unify /proc/slabinfo configuration

Both SLUB and SLAB really did almost exactly the same thing for
/proc/slabinfo setup, using duplicate code and per-allocator #ifdef's.

This just creates a common CONFIG_SLABINFO that is enabled by both SLUB
and SLAB, and shares all the setup code.  Maybe SLOB will want this some
day too.

Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index a11968b..3462bfd 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -410,7 +410,7 @@
 };
 #endif
 
-#ifdef CONFIG_SLAB
+#ifdef CONFIG_SLABINFO
 static int slabinfo_open(struct inode *inode, struct file *file)
 {
 	return seq_open(file, &slabinfo_op);
@@ -451,20 +451,6 @@
 #endif
 #endif
 
-#ifdef CONFIG_SLUB
-static int slabinfo_open(struct inode *inode, struct file *file)
-{
-	return seq_open(file, &slabinfo_op);
-}
-
-static const struct file_operations proc_slabinfo_operations = {
-	.open		= slabinfo_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= seq_release,
-};
-#endif
-
 static int show_stat(struct seq_file *p, void *v)
 {
 	int i;
@@ -742,15 +728,12 @@
 #endif
 	create_seq_entry("stat", 0, &proc_stat_operations);
 	create_seq_entry("interrupts", 0, &proc_interrupts_operations);
-#ifdef CONFIG_SLAB
+#ifdef CONFIG_SLABINFO
 	create_seq_entry("slabinfo",S_IWUSR|S_IRUGO,&proc_slabinfo_operations);
 #ifdef CONFIG_DEBUG_SLAB_LEAK
 	create_seq_entry("slab_allocators", 0 ,&proc_slabstats_operations);
 #endif
 #endif
-#ifdef CONFIG_SLUB
-	create_seq_entry("slabinfo", S_IWUSR|S_IRUGO, &proc_slabinfo_operations);
-#endif
 	create_seq_entry("buddyinfo",S_IRUGO, &fragmentation_file_operations);
 	create_seq_entry("pagetypeinfo", S_IRUGO, &pagetypeinfo_file_ops);
 	create_seq_entry("vmstat",S_IRUGO, &proc_vmstat_file_operations);