Just do a simple list_for_each_entry_safe on all_mddevs, and only grab a reference when we drop the lock and delete the now unused for_each_mddev macro. Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxx> --- drivers/md/md.c | 39 +++++++++++---------------------------- 1 file changed, 11 insertions(+), 28 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index ede817286cacd..ee3e9ba03fd25 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -368,28 +368,6 @@ EXPORT_SYMBOL_GPL(md_new_event); static LIST_HEAD(all_mddevs); static DEFINE_SPINLOCK(all_mddevs_lock); -/* - * iterates through all used mddevs in the system. - * We take care to grab the all_mddevs_lock whenever navigating - * the list, and to always hold a refcount when unlocked. - * Any code which breaks out of this loop while own - * a reference to the current mddev and must mddev_put it. - */ -#define for_each_mddev(_mddev,_tmp) \ - \ - for (({ spin_lock(&all_mddevs_lock); \ - _tmp = all_mddevs.next; \ - _mddev = NULL;}); \ - ({ if (_tmp != &all_mddevs) \ - mddev_get(list_entry(_tmp, struct mddev, all_mddevs));\ - spin_unlock(&all_mddevs_lock); \ - if (_mddev) mddev_put(_mddev); \ - _mddev = list_entry(_tmp, struct mddev, all_mddevs); \ - _tmp != &all_mddevs;}); \ - ({ spin_lock(&all_mddevs_lock); \ - _tmp = _tmp->next;}) \ - ) - /* Rather than calling directly into the personality make_request function, * IO requests come here first so that we can check if the device is * being suspended pending a reconfiguration. @@ -9923,8 +9901,7 @@ void md_autostart_arrays(int part) static __exit void md_exit(void) { - struct mddev *mddev; - struct list_head *tmp; + struct mddev *mddev, *n; int delay = 1; unregister_blkdev(MD_MAJOR,"md"); @@ -9944,17 +9921,23 @@ static __exit void md_exit(void) } remove_proc_entry("mdstat", NULL); - for_each_mddev(mddev, tmp) { + spin_lock(&all_mddevs_lock); + list_for_each_entry_safe(mddev, n, &all_mddevs, all_mddevs) { + mddev_get(mddev); + spin_unlock(&all_mddevs_lock); export_array(mddev); mddev->ctime = 0; mddev->hold_active = 0; /* - * for_each_mddev() will call mddev_put() at the end of each - * iteration. As the mddev is now fully clear, this will - * schedule the mddev for destruction by a workqueue, and the + * As the mddev is now fully clear, mddev_put will schedule + * the mddev for destruction by a workqueue, and the * destroy_workqueue() below will wait for that to complete. */ + mddev_put(mddev); + spin_lock(&all_mddevs_lock); } + spin_unlock(&all_mddevs_lock); + destroy_workqueue(md_rdev_misc_wq); destroy_workqueue(md_misc_wq); destroy_workqueue(md_wq); -- 2.30.2