writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
Currently, majority of cgroup writeback support including all the
above functions are implemented in include/linux/backing-dev.h and
mm/backing-dev.c; however, the portion closely related to writeback
logic implemented in include/linux/writeback.h and mm/page-writeback.c
will expand to support foreign writeback detection and correction.
This patch moves wb[_try]_get() and wb_put() to
include/linux/backing-dev-defs.h so that they can be used from
writeback.h and inode_{attach|detach}_wb() to writeback.h and
page-writeback.c.
This is pure reorganization and doesn't introduce any functional
changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
(cherry picked from commit 21c6321fbb3a3787af07f1bc031d713a707fb69c)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index 8d470b7..e047b49 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -186,4 +186,54 @@
set_wb_congested(bdi->wb.congested, sync);
}
+#ifdef CONFIG_CGROUP_WRITEBACK
+
+/**
+ * wb_tryget - try to increment a wb's refcount
+ * @wb: bdi_writeback to get
+ */
+static inline bool wb_tryget(struct bdi_writeback *wb)
+{
+ if (wb != &wb->bdi->wb)
+ return percpu_ref_tryget(&wb->refcnt);
+ return true;
+}
+
+/**
+ * wb_get - increment a wb's refcount
+ * @wb: bdi_writeback to get
+ */
+static inline void wb_get(struct bdi_writeback *wb)
+{
+ if (wb != &wb->bdi->wb)
+ percpu_ref_get(&wb->refcnt);
+}
+
+/**
+ * wb_put - decrement a wb's refcount
+ * @wb: bdi_writeback to put
+ */
+static inline void wb_put(struct bdi_writeback *wb)
+{
+ if (wb != &wb->bdi->wb)
+ percpu_ref_put(&wb->refcnt);
+}
+
+#else /* CONFIG_CGROUP_WRITEBACK */
+
+static inline bool wb_tryget(struct bdi_writeback *wb)
+{
+ return true;
+}
+
+static inline void wb_get(struct bdi_writeback *wb)
+{
+}
+
+static inline void wb_put(struct bdi_writeback *wb)
+{
+}
+
+#endif /* CONFIG_CGROUP_WRITEBACK */
+
#endif /* __LINUX_BACKING_DEV_DEFS_H */
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 677e22cf..954982c 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -242,7 +242,6 @@
struct bdi_writeback *wb_get_create(struct backing_dev_info *bdi,
struct cgroup_subsys_state *memcg_css,
gfp_t gfp);
-void __inode_attach_wb(struct inode *inode, struct page *page);
void wb_memcg_offline(struct mem_cgroup *memcg);
void wb_blkcg_offline(struct blkcg *blkcg);
int inode_congested(struct inode *inode, int cong_bits);
@@ -264,37 +263,6 @@
}
/**
- * wb_tryget - try to increment a wb's refcount
- * @wb: bdi_writeback to get
- */
-static inline bool wb_tryget(struct bdi_writeback *wb)
-{
- if (wb != &wb->bdi->wb)
- return percpu_ref_tryget(&wb->refcnt);
- return true;
-}
-
-/**
- * wb_get - increment a wb's refcount
- * @wb: bdi_writeback to get
- */
-static inline void wb_get(struct bdi_writeback *wb)
-{
- if (wb != &wb->bdi->wb)
- percpu_ref_get(&wb->refcnt);
-}
-
-/**
- * wb_put - decrement a wb's refcount
- * @wb: bdi_writeback to put
- */
-static inline void wb_put(struct bdi_writeback *wb)
-{
- if (wb != &wb->bdi->wb)
- percpu_ref_put(&wb->refcnt);
-}
-
-/**
* wb_find_current - find wb for %current on a bdi
* @bdi: bdi of interest
*
@@ -353,35 +321,6 @@
}
/**
- * inode_attach_wb - associate an inode with its wb
- * @inode: inode of interest
- * @page: page being dirtied (may be NULL)
- *
- * If @inode doesn't have its wb, associate it with the wb matching the
- * memcg of @page or, if @page is NULL, %current. May be called w/ or w/o
- * @inode->i_lock.
- */
-static inline void inode_attach_wb(struct inode *inode, struct page *page)
-{
- if (!inode->i_wb)
- __inode_attach_wb(inode, page);
-}
-
-/**
- * inode_detach_wb - disassociate an inode from its wb
- * @inode: inode of interest
- *
- * @inode is being freed. Detach from its wb.
- */
-static inline void inode_detach_wb(struct inode *inode)
-{
- if (inode->i_wb) {
- wb_put(inode->i_wb);
- inode->i_wb = NULL;
- }
-}
-
-/**
* inode_to_wb - determine the wb of an inode
* @inode: inode of interest
*
@@ -470,19 +409,6 @@
{
}
-static inline bool wb_tryget(struct bdi_writeback *wb)
-{
- return true;
-}
-
-static inline void wb_get(struct bdi_writeback *wb)
-{
-}
-
-static inline void wb_put(struct bdi_writeback *wb)
-{
-}
-
static inline struct bdi_writeback *wb_find_current(struct backing_dev_info *bdi)
{
return &bdi->wb;
@@ -494,14 +420,6 @@
return &bdi->wb;
}
-static inline void inode_attach_wb(struct inode *inode, struct page *page)
-{
-}
-
-static inline void inode_detach_wb(struct inode *inode)
-{
-}
-
static inline struct bdi_writeback *inode_to_wb(struct inode *inode)
{
return &inode_to_bdi(inode)->wb;
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 3b73e97..6726b7e 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -8,6 +8,7 @@
#include <linux/workqueue.h>
#include <linux/fs.h>
#include <linux/flex_proportions.h>
+#include <linux/backing-dev-defs.h>
DECLARE_PER_CPU(int, dirty_throttle_leaks);
@@ -173,6 +174,51 @@
wait_on_bit(&inode->i_state, __I_NEW, TASK_UNINTERRUPTIBLE);
}
+#ifdef CONFIG_CGROUP_WRITEBACK
+
+void __inode_attach_wb(struct inode *inode, struct page *page);
+
+/**
+ * inode_attach_wb - associate an inode with its wb
+ * @inode: inode of interest
+ * @page: page being dirtied (may be NULL)
+ *
+ * If @inode doesn't have its wb, associate it with the wb matching the
+ * memcg of @page or, if @page is NULL, %current. May be called w/ or w/o
+ * @inode->i_lock.
+ */
+static inline void inode_attach_wb(struct inode *inode, struct page *page)
+{
+ if (!inode->i_wb)
+ __inode_attach_wb(inode, page);
+}
+
+/**
+ * inode_detach_wb - disassociate an inode from its wb
+ * @inode: inode of interest
+ *
+ * @inode is being freed. Detach from its wb.
+ */
+static inline void inode_detach_wb(struct inode *inode)
+{
+ if (inode->i_wb) {
+ wb_put(inode->i_wb);
+ inode->i_wb = NULL;
+ }
+}
+
+#else /* CONFIG_CGROUP_WRITEBACK */
+
+static inline void inode_attach_wb(struct inode *inode, struct page *page)
+{
+}
+
+static inline void inode_detach_wb(struct inode *inode)
+{
+}
+
+#endif /* CONFIG_CGROUP_WRITEBACK */
+
/*
* mm/page-writeback.c
*/