proc: move /proc/slab_allocators boilerplate to mm/slab.c

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>

1 files changed, 35 insertions, 1 deletions

diff --git a/mm/slab.c b/mm/slab.c
index e76eee466886..d53ac9c26ab7 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -95,6 +95,7 @@
 #include        <linux/init.h>
 #include        <linux/compiler.h>
 #include        <linux/cpuset.h>
+#include        <linux/proc_fs.h>
 #include        <linux/seq_file.h>
 #include        <linux/notifier.h>
 #include        <linux/kallsyms.h>
@@ -4443,13 +4444,46 @@ static int leaks_show(struct seq_file *m, void *p)
         return 0;
 }
 
-const struct seq_operations slabstats_op = {
+static const struct seq_operations slabstats_op = {
         .start = leaks_start,
         .next = s_next,
         .stop = s_stop,
         .show = leaks_show,
 };
+
+static int slabstats_open(struct inode *inode, struct file *file)
+{
+        unsigned long *n = kzalloc(PAGE_SIZE, GFP_KERNEL);
+        int ret = -ENOMEM;
+        if (n) {
+                ret = seq_open(file, &slabstats_op);
+                if (!ret) {
+                        struct seq_file *m = file->private_data;
+                        *n = PAGE_SIZE / (2 * sizeof(unsigned long));
+                        m->private = n;
+                        n = NULL;
+                }
+                kfree(n);
+        }
+        return ret;
+}
+
+static const struct file_operations proc_slabstats_operations = {
+        .open           = slabstats_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = seq_release_private,
+};
+#endif
+
+static int __init slab_proc_init(void)
+{
+#ifdef CONFIG_DEBUG_SLAB_LEAK
+        proc_create("slab_allocators", 0, NULL, &proc_slabstats_operations);
 #endif
+        return 0;
+}
+module_init(slab_proc_init);
 #endif
 
 /**