writeback, cgroup: keep list of inodes attached to bdi_writeback (f3b6a6df) · Commits · EulixOS / Software / Kernel

fs/fs-writeback.c

+59 −34

Original line number	Diff line number	Diff line
		@@ -131,25 +131,6 @@ static bool inode_io_list_move_locked(struct inode *inode,
		return false;
		}

		/**
		* inode_io_list_del_locked - remove an inode from its bdi_writeback IO list
		* @inode: inode to be removed
		* @wb: bdi_writeback @inode is being removed from
		*
		* Remove @inode which may be on one of @wb->b_{dirty\|io\|more_io} lists and
		* clear %WB_has_dirty_io if all are empty afterwards.
		*/
		static void inode_io_list_del_locked(struct inode *inode,
		struct bdi_writeback *wb)
		{
		assert_spin_locked(&wb->list_lock);
		assert_spin_locked(&inode->i_lock);

		inode->i_state &= ~I_SYNC_QUEUED;
		list_del_init(&inode->i_io_list);
		wb_io_lists_depopulated(wb);
		}

		static void wb_wakeup(struct bdi_writeback *wb)
		{
		spin_lock_bh(&wb->work_lock);
		@@ -278,6 +259,28 @@ void __inode_attach_wb(struct inode inode, struct page page)
		}
		EXPORT_SYMBOL_GPL(__inode_attach_wb);

		/**
		* inode_cgwb_move_to_attached - put the inode onto wb->b_attached list
		* @inode: inode of interest with i_lock held
		* @wb: target bdi_writeback
		*
		* Remove the inode from wb's io lists and if necessarily put onto b_attached
		* list. Only inodes attached to cgwb's are kept on this list.
		*/
		static void inode_cgwb_move_to_attached(struct inode *inode,
		struct bdi_writeback *wb)
		{
		assert_spin_locked(&wb->list_lock);
		assert_spin_locked(&inode->i_lock);

		inode->i_state &= ~I_SYNC_QUEUED;
		if (wb != &wb->bdi->wb)
		list_move(&inode->i_io_list, &wb->b_attached);
		else
		list_del_init(&inode->i_io_list);
		wb_io_lists_depopulated(wb);
		}

		/**
		* locked_inode_to_wb_and_lock_list - determine a locked inode's wb and lock it
		* @inode: inode of interest with i_lock held
		@@ -418,21 +421,28 @@ static void inode_switch_wbs_work_fn(struct work_struct *work)
		wb_get(new_wb);

		/*
		* Transfer to @new_wb's IO list if necessary. The specific list
		* @inode was on is ignored and the inode is put on ->b_dirty which
		* is always correct including from ->b_dirty_time. The transfer
		* preserves @inode->dirtied_when ordering.
		* Transfer to @new_wb's IO list if necessary. If the @inode is dirty,
		* the specific list @inode was on is ignored and the @inode is put on
		* ->b_dirty which is always correct including from ->b_dirty_time.
		* The transfer preserves @inode->dirtied_when ordering. If the @inode
		* was clean, it means it was on the b_attached list, so move it onto
		* the b_attached list of @new_wb.
		*/
		if (!list_empty(&inode->i_io_list)) {
		inode->i_wb = new_wb;

		if (inode->i_state & I_DIRTY_ALL) {
		struct inode *pos;

		inode_io_list_del_locked(inode, old_wb);
		inode->i_wb = new_wb;
		list_for_each_entry(pos, &new_wb->b_dirty, i_io_list)
		if (time_after_eq(inode->dirtied_when,
		pos->dirtied_when))
		break;
		inode_io_list_move_locked(inode, new_wb, pos->i_io_list.prev);
		inode_io_list_move_locked(inode, new_wb,
		pos->i_io_list.prev);
		} else {
		inode_cgwb_move_to_attached(inode, new_wb);
		}
		} else {
		inode->i_wb = new_wb;
		}
		@@ -1021,6 +1031,17 @@ fs_initcall(cgroup_writeback_init);
		static void bdi_down_write_wb_switch_rwsem(struct backing_dev_info *bdi) { }
		static void bdi_up_write_wb_switch_rwsem(struct backing_dev_info *bdi) { }

		static void inode_cgwb_move_to_attached(struct inode *inode,
		struct bdi_writeback *wb)
		{
		assert_spin_locked(&wb->list_lock);
		assert_spin_locked(&inode->i_lock);

		inode->i_state &= ~I_SYNC_QUEUED;
		list_del_init(&inode->i_io_list);
		wb_io_lists_depopulated(wb);
		}

		static struct bdi_writeback *
		locked_inode_to_wb_and_lock_list(struct inode *inode)
		__releases(&inode->i_lock)
		@@ -1121,7 +1142,11 @@ void inode_io_list_del(struct inode *inode)

		wb = inode_to_wb_and_lock_list(inode);
		spin_lock(&inode->i_lock);
		inode_io_list_del_locked(inode, wb);

		inode->i_state &= ~I_SYNC_QUEUED;
		list_del_init(&inode->i_io_list);
		wb_io_lists_depopulated(wb);

		spin_unlock(&inode->i_lock);
		spin_unlock(&wb->list_lock);
		}
		@@ -1434,7 +1459,7 @@ static void requeue_inode(struct inode inode, struct bdi_writeback wb,
		inode->i_state &= ~I_SYNC_QUEUED;
		} else {
		/* The inode is clean. Remove from writeback lists. */
		inode_io_list_del_locked(inode, wb);
		inode_cgwb_move_to_attached(inode, wb);
		}
		}

		@@ -1586,7 +1611,7 @@ static int writeback_single_inode(struct inode *inode,
		* responsible for the writeback lists.
		*/
		if (!(inode->i_state & I_DIRTY_ALL))
		inode_io_list_del_locked(inode, wb);
		inode_cgwb_move_to_attached(inode, wb);
		spin_unlock(&wb->list_lock);
		inode_sync_complete(inode);
		out:

include/linux/backing-dev-defs.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -154,6 +154,7 @@ struct bdi_writeback {
		struct cgroup_subsys_state blkcg_css; / and blkcg */
		struct list_head memcg_node; /* anchored at memcg->cgwb_list */
		struct list_head blkcg_node; /* anchored at blkcg->cgwb_list */
		struct list_head b_attached; /* attached inodes, protected by list_lock */

		union {
		struct work_struct release_work;

mm/backing-dev.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -396,6 +396,7 @@ static void cgwb_release_workfn(struct work_struct *work)
		fprop_local_destroy_percpu(&wb->memcg_completions);
		percpu_ref_exit(&wb->refcnt);
		wb_exit(wb);
		WARN_ON_ONCE(!list_empty(&wb->b_attached));
		kfree_rcu(wb, rcu);
		}

		@@ -472,6 +473,7 @@ static int cgwb_create(struct backing_dev_info *bdi,

		wb->memcg_css = memcg_css;
		wb->blkcg_css = blkcg_css;
		INIT_LIST_HEAD(&wb->b_attached);
		INIT_WORK(&wb->release_work, cgwb_release_workfn);
		set_bit(WB_registered, &wb->state);