xfs: pass xfsstats structures to handlers and macros

This patch is the next step toward per-fs xfs stats. The patch makes
the show and clear routines able to handle any stats structure
associated with a kobject.

Instead of a single global xfsstats structure, add kobject and a pointer
to a per-cpu struct xfsstats. Modify the macros that manipulate the stats
accordingly: XFS_STATS_INC, XFS_STATS_DEC, and XFS_STATS_ADD now access
xfsstats->xs_stats.

The sysfs functions need to get from the kobject back to the xfsstats
structure which contains it, and pass the pointer to the ->xs_stats
percpu structure into the show & clear routines.

Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 14 insertions, 2 deletions

diff --git a/fs/xfs/xfs_sysfs.c b/fs/xfs/xfs_sysfs.c
index fa3dc66d82f1..ee70f5dec9dc 100644
--- a/fs/xfs/xfs_sysfs.c
+++ b/fs/xfs/xfs_sysfs.c
@@ -131,12 +131,22 @@ struct kobj_type xfs_dbg_ktype = {
 
 /* stats */
 
+static inline struct xstats *
+to_xstats(struct kobject *kobject)
+{
+	struct xfs_kobj *kobj = to_kobj(kobject);
+
+	return container_of(kobj, struct xstats, xs_kobj);
+}
+
 STATIC ssize_t
 stats_show(
 	struct kobject	*kobject,
 	char		*buf)
 {
-	return xfs_stats_format(buf);
+	struct xstats	*stats = to_xstats(kobject);
+
+	return xfs_stats_format(stats->xs_stats, buf);
 }
 XFS_SYSFS_ATTR_RO(stats);
 
@@ -148,6 +158,7 @@ stats_clear_store(
 {
 	int		ret;
 	int		val;
+	struct xstats	*stats = to_xstats(kobject);
 
 	ret = kstrtoint(buf, 0, &val);
 	if (ret)
@@ -155,7 +166,8 @@ stats_clear_store(
 
 	if (val != 1)
 		return -EINVAL;
-	xfs_stats_clearall();
+
+	xfs_stats_clearall(stats->xs_stats);
 	return count;
 }
 XFS_SYSFS_ATTR_WO(stats_clear);