mm: cleancache: report statistics via debugfs instead of sysfs.
[v9: akpm@linux-foundation.org: sysfs->debugfs; no longer need Doc/ABI file]
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Jan Beulich <JBeulich@novell.com>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Rik Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
diff --git a/mm/cleancache.c b/mm/cleancache.c
index b9c198b..deb9f2c 100644
--- a/mm/cleancache.c
+++ b/mm/cleancache.c
@@ -15,6 +15,7 @@
#include <linux/fs.h>
#include <linux/exportfs.h>
#include <linux/mm.h>
+#include <linux/debugfs.h>
#include <linux/cleancache.h>
/*
@@ -33,11 +34,15 @@
*/
static struct cleancache_ops cleancache_ops;
-/* useful stats available in /sys/kernel/mm/cleancache */
-static unsigned long cleancache_succ_gets;
-static unsigned long cleancache_failed_gets;
-static unsigned long cleancache_puts;
-static unsigned long cleancache_flushes;
+/*
+ * Counters available via /sys/kernel/debug/frontswap (if debugfs is
+ * properly configured. These are for information only so are not protected
+ * against increment races.
+ */
+static u64 cleancache_succ_gets;
+static u64 cleancache_failed_gets;
+static u64 cleancache_puts;
+static u64 cleancache_invalidates;
/*
* register operations for cleancache, returning previous thus allowing
@@ -163,7 +168,7 @@
if (cleancache_get_key(mapping->host, &key) >= 0) {
(*cleancache_ops.invalidate_page)(pool_id,
key, page->index);
- cleancache_flushes++;
+ cleancache_invalidates++;
}
}
}
@@ -199,48 +204,19 @@
}
EXPORT_SYMBOL(__cleancache_invalidate_fs);
-#ifdef CONFIG_SYSFS
-
-/* see Documentation/ABI/xxx/sysfs-kernel-mm-cleancache */
-
-#define CLEANCACHE_SYSFS_RO(_name) \
- static ssize_t cleancache_##_name##_show(struct kobject *kobj, \
- struct kobj_attribute *attr, char *buf) \
- { \
- return sprintf(buf, "%lu\n", cleancache_##_name); \
- } \
- static struct kobj_attribute cleancache_##_name##_attr = { \
- .attr = { .name = __stringify(_name), .mode = 0444 }, \
- .show = cleancache_##_name##_show, \
- }
-
-CLEANCACHE_SYSFS_RO(succ_gets);
-CLEANCACHE_SYSFS_RO(failed_gets);
-CLEANCACHE_SYSFS_RO(puts);
-CLEANCACHE_SYSFS_RO(flushes);
-
-static struct attribute *cleancache_attrs[] = {
- &cleancache_succ_gets_attr.attr,
- &cleancache_failed_gets_attr.attr,
- &cleancache_puts_attr.attr,
- &cleancache_flushes_attr.attr,
- NULL,
-};
-
-static struct attribute_group cleancache_attr_group = {
- .attrs = cleancache_attrs,
- .name = "cleancache",
-};
-
-#endif /* CONFIG_SYSFS */
-
static int __init init_cleancache(void)
{
-#ifdef CONFIG_SYSFS
- int err;
-
- err = sysfs_create_group(mm_kobj, &cleancache_attr_group);
-#endif /* CONFIG_SYSFS */
+#ifdef CONFIG_DEBUG_FS
+ struct dentry *root = debugfs_create_dir("cleancache", NULL);
+ if (root == NULL)
+ return -ENXIO;
+ debugfs_create_u64("succ_gets", S_IRUGO, root, &cleancache_succ_gets);
+ debugfs_create_u64("failed_gets", S_IRUGO,
+ root, &cleancache_failed_gets);
+ debugfs_create_u64("puts", S_IRUGO, root, &cleancache_puts);
+ debugfs_create_u64("invalidates", S_IRUGO,
+ root, &cleancache_invalidates);
+#endif
return 0;
}
module_init(init_cleancache)