| Message ID | 20210603005517.1403689-2-guro@fb.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | cgroup, blkcg: prevent dirty inodes to pin dying memory cgroups | expand |
On Wed 02-06-21 17:55:13, Roman Gushchin wrote: > Inode's wb switching requires two steps divided by an RCU grace > period. It's currently implemented as an RCU callback > inode_switch_wbs_rcu_fn(), which schedules inode_switch_wbs_work_fn() > as a work. > > Switching to the rcu_work API allows to do the same in a cleaner and > slightly shorter form. > > Signed-off-by: Roman Gushchin <guro@fb.com> Looks good to me. You can add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > fs/fs-writeback.c | 18 ++++-------------- > 1 file changed, 4 insertions(+), 14 deletions(-) > > diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c > index e91980f49388..1f51857e41d1 100644 > --- a/fs/fs-writeback.c > +++ b/fs/fs-writeback.c > @@ -335,8 +335,7 @@ struct inode_switch_wbs_context { > struct inode *inode; > struct bdi_writeback *new_wb; > > - struct rcu_head rcu_head; > - struct work_struct work; > + struct rcu_work work; > }; > > static void bdi_down_write_wb_switch_rwsem(struct backing_dev_info *bdi) > @@ -352,7 +351,7 @@ static void bdi_up_write_wb_switch_rwsem(struct backing_dev_info *bdi) > static void inode_switch_wbs_work_fn(struct work_struct *work) > { > struct inode_switch_wbs_context *isw = > - container_of(work, struct inode_switch_wbs_context, work); > + container_of(to_rcu_work(work), struct inode_switch_wbs_context, work); > struct inode *inode = isw->inode; > struct backing_dev_info *bdi = inode_to_bdi(inode); > struct address_space *mapping = inode->i_mapping; > @@ -469,16 +468,6 @@ static void inode_switch_wbs_work_fn(struct work_struct *work) > atomic_dec(&isw_nr_in_flight); > } > > -static void inode_switch_wbs_rcu_fn(struct rcu_head *rcu_head) > -{ > - struct inode_switch_wbs_context *isw = container_of(rcu_head, > - struct inode_switch_wbs_context, rcu_head); > - > - /* needs to grab bh-unsafe locks, bounce to work item */ > - INIT_WORK(&isw->work, inode_switch_wbs_work_fn); > - queue_work(isw_wq, &isw->work); > -} > - > /** > * inode_switch_wbs - change the wb association of an inode > * @inode: target inode > @@ -534,7 +523,8 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id) > * lock so that stat transfer can synchronize against them. > * Let's continue after I_WB_SWITCH is guaranteed to be visible. > */ > - call_rcu(&isw->rcu_head, inode_switch_wbs_rcu_fn); > + INIT_RCU_WORK(&isw->work, inode_switch_wbs_work_fn); > + queue_rcu_work(isw_wq, &isw->work); > > atomic_inc(&isw_nr_in_flight); > return; > -- > 2.31.1 >
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index e91980f49388..1f51857e41d1 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -335,8 +335,7 @@ struct inode_switch_wbs_context { struct inode *inode; struct bdi_writeback *new_wb; - struct rcu_head rcu_head; - struct work_struct work; + struct rcu_work work; }; static void bdi_down_write_wb_switch_rwsem(struct backing_dev_info *bdi) @@ -352,7 +351,7 @@ static void bdi_up_write_wb_switch_rwsem(struct backing_dev_info *bdi) static void inode_switch_wbs_work_fn(struct work_struct *work) { struct inode_switch_wbs_context *isw = - container_of(work, struct inode_switch_wbs_context, work); + container_of(to_rcu_work(work), struct inode_switch_wbs_context, work); struct inode *inode = isw->inode; struct backing_dev_info *bdi = inode_to_bdi(inode); struct address_space *mapping = inode->i_mapping; @@ -469,16 +468,6 @@ static void inode_switch_wbs_work_fn(struct work_struct *work) atomic_dec(&isw_nr_in_flight); } -static void inode_switch_wbs_rcu_fn(struct rcu_head *rcu_head) -{ - struct inode_switch_wbs_context *isw = container_of(rcu_head, - struct inode_switch_wbs_context, rcu_head); - - /* needs to grab bh-unsafe locks, bounce to work item */ - INIT_WORK(&isw->work, inode_switch_wbs_work_fn); - queue_work(isw_wq, &isw->work); -} - /** * inode_switch_wbs - change the wb association of an inode * @inode: target inode @@ -534,7 +523,8 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id) * lock so that stat transfer can synchronize against them. * Let's continue after I_WB_SWITCH is guaranteed to be visible. */ - call_rcu(&isw->rcu_head, inode_switch_wbs_rcu_fn); + INIT_RCU_WORK(&isw->work, inode_switch_wbs_work_fn); + queue_rcu_work(isw_wq, &isw->work); atomic_inc(&isw_nr_in_flight); return;
Inode's wb switching requires two steps divided by an RCU grace period. It's currently implemented as an RCU callback inode_switch_wbs_rcu_fn(), which schedules inode_switch_wbs_work_fn() as a work. Switching to the rcu_work API allows to do the same in a cleaner and slightly shorter form. Signed-off-by: Roman Gushchin <guro@fb.com> --- fs/fs-writeback.c | 18 ++++-------------- 1 file changed, 4 insertions(+), 14 deletions(-)