From 1643dfa4c2c827d6e2aa419df8c17b0f24090278 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Fri, 12 Aug 2016 15:45:52 +0200 Subject: [PATCH] rbd: introduce a per-device ordered workqueue This is going to be used for re-registering watch requests and exclusive-lock tasks: acquire/request lock, notify-acquired, release lock, notify-released. Some refactoring in the map/unmap paths was necessary to give this workqueue a meaningful name: "rbdX-tasks". Signed-off-by: Ilya Dryomov Reviewed-by: Mike Christie --- drivers/block/rbd.c | 151 +++++++++++++++++++++----------------------- 1 file changed, 71 insertions(+), 80 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index e0585e9040f1..1c805eea6767 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -128,11 +128,8 @@ static int atomic_dec_return_safe(atomic_t *v) /* * An RBD device name will be "rbd#", where the "rbd" comes from * RBD_DRV_NAME above, and # is a unique integer identifier. - * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big - * enough to hold all possible device names. */ #define DEV_NAME_LEN 32 -#define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1) /* * block device image metadata (in-memory version) @@ -353,10 +350,12 @@ struct rbd_device { struct ceph_object_id header_oid; struct ceph_object_locator header_oloc; - struct ceph_file_layout layout; + struct ceph_file_layout layout; /* used for all rbd requests */ struct ceph_osd_linger_request *watch_handle; + struct workqueue_struct *task_wq; + struct rbd_spec *parent_spec; u64 parent_overlap; atomic_t parent_ref; @@ -3944,11 +3943,8 @@ static void rbd_spec_free(struct kref *kref) kfree(spec); } -static void rbd_dev_release(struct device *dev) +static void rbd_dev_free(struct rbd_device *rbd_dev) { - struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); - bool need_put = !!rbd_dev->opts; - ceph_oid_destroy(&rbd_dev->header_oid); ceph_oloc_destroy(&rbd_dev->header_oloc); @@ -3956,6 +3952,19 @@ static void rbd_dev_release(struct device *dev) rbd_spec_put(rbd_dev->spec); kfree(rbd_dev->opts); kfree(rbd_dev); +} + +static void rbd_dev_release(struct device *dev) +{ + struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); + bool need_put = !!rbd_dev->opts; + + if (need_put) { + destroy_workqueue(rbd_dev->task_wq); + ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); + } + + rbd_dev_free(rbd_dev); /* * This is racy, but way better than putting module outside of @@ -3966,19 +3975,16 @@ static void rbd_dev_release(struct device *dev) module_put(THIS_MODULE); } -static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, - struct rbd_spec *spec, - struct rbd_options *opts) +static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc, + struct rbd_spec *spec) { struct rbd_device *rbd_dev; - rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL); + rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL); if (!rbd_dev) return NULL; spin_lock_init(&rbd_dev->lock); - rbd_dev->flags = 0; - atomic_set(&rbd_dev->parent_ref, 0); INIT_LIST_HEAD(&rbd_dev->node); init_rwsem(&rbd_dev->header_rwsem); @@ -3992,9 +3998,6 @@ static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, rbd_dev->rbd_client = rbdc; rbd_dev->spec = spec; - rbd_dev->opts = opts; - - /* Initialize the layout used for all rbd requests */ rbd_dev->layout.stripe_unit = 1 << RBD_MAX_OBJ_ORDER; rbd_dev->layout.stripe_count = 1; @@ -4002,15 +4005,48 @@ static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, rbd_dev->layout.pool_id = spec->pool_id; RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL); - /* - * If this is a mapping rbd_dev (as opposed to a parent one), - * pin our module. We have a ref from do_rbd_add(), so use - * __module_get(). - */ - if (rbd_dev->opts) - __module_get(THIS_MODULE); + return rbd_dev; +} + +/* + * Create a mapping rbd_dev. + */ +static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, + struct rbd_spec *spec, + struct rbd_options *opts) +{ + struct rbd_device *rbd_dev; + + rbd_dev = __rbd_dev_create(rbdc, spec); + if (!rbd_dev) + return NULL; + + rbd_dev->opts = opts; + + /* get an id and fill in device name */ + rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0, + minor_to_rbd_dev_id(1 << MINORBITS), + GFP_KERNEL); + if (rbd_dev->dev_id < 0) + goto fail_rbd_dev; + + sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id); + rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM, + rbd_dev->name); + if (!rbd_dev->task_wq) + goto fail_dev_id; + /* we have a ref from do_rbd_add() */ + __module_get(THIS_MODULE); + + dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id); return rbd_dev; + +fail_dev_id: + ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); +fail_rbd_dev: + rbd_dev_free(rbd_dev); + return NULL; } static void rbd_dev_destroy(struct rbd_device *rbd_dev) @@ -4645,46 +4681,6 @@ static int rbd_dev_header_info(struct rbd_device *rbd_dev) return rbd_dev_v2_header_info(rbd_dev); } -/* - * Get a unique rbd identifier for the given new rbd_dev, and add - * the rbd_dev to the global list. - */ -static int rbd_dev_id_get(struct rbd_device *rbd_dev) -{ - int new_dev_id; - - new_dev_id = ida_simple_get(&rbd_dev_id_ida, - 0, minor_to_rbd_dev_id(1 << MINORBITS), - GFP_KERNEL); - if (new_dev_id < 0) - return new_dev_id; - - rbd_dev->dev_id = new_dev_id; - - spin_lock(&rbd_dev_list_lock); - list_add_tail(&rbd_dev->node, &rbd_dev_list); - spin_unlock(&rbd_dev_list_lock); - - dout("rbd_dev %p given dev id %d\n", rbd_dev, rbd_dev->dev_id); - - return 0; -} - -/* - * Remove an rbd_dev from the global list, and record that its - * identifier is no longer in use. - */ -static void rbd_dev_id_put(struct rbd_device *rbd_dev) -{ - spin_lock(&rbd_dev_list_lock); - list_del_init(&rbd_dev->node); - spin_unlock(&rbd_dev_list_lock); - - ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); - - dout("rbd_dev %p released dev id %d\n", rbd_dev, rbd_dev->dev_id); -} - /* * Skips over white space at *buf, and updates *buf to point to the * first found non-space character (if any). Returns the length of @@ -5077,8 +5073,7 @@ static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth) goto out_err; } - parent = rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec, - NULL); + parent = __rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec); if (!parent) { ret = -ENOMEM; goto out_err; @@ -5113,22 +5108,12 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev) { int ret; - /* Get an id and fill in device name. */ - - ret = rbd_dev_id_get(rbd_dev); - if (ret) - goto err_out_unlock; - - BUILD_BUG_ON(DEV_NAME_LEN - < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH); - sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id); - /* Record our major and minor device numbers. */ if (!single_major) { ret = register_blkdev(0, rbd_dev->name); if (ret < 0) - goto err_out_id; + goto err_out_unlock; rbd_dev->major = ret; rbd_dev->minor = 0; @@ -5160,6 +5145,10 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev) set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); up_write(&rbd_dev->header_rwsem); + spin_lock(&rbd_dev_list_lock); + list_add_tail(&rbd_dev->node, &rbd_dev_list); + spin_unlock(&rbd_dev_list_lock); + add_disk(rbd_dev->disk); pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name, (unsigned long long) rbd_dev->mapping.size); @@ -5173,8 +5162,6 @@ err_out_disk: err_out_blkdev: if (!single_major) unregister_blkdev(rbd_dev->major, rbd_dev->name); -err_out_id: - rbd_dev_id_put(rbd_dev); err_out_unlock: up_write(&rbd_dev->header_rwsem); return ret; @@ -5406,12 +5393,16 @@ static ssize_t rbd_add_single_major(struct bus_type *bus, static void rbd_dev_device_release(struct rbd_device *rbd_dev) { rbd_free_disk(rbd_dev); + + spin_lock(&rbd_dev_list_lock); + list_del_init(&rbd_dev->node); + spin_unlock(&rbd_dev_list_lock); + clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); device_del(&rbd_dev->dev); rbd_dev_mapping_clear(rbd_dev); if (!single_major) unregister_blkdev(rbd_dev->major, rbd_dev->name); - rbd_dev_id_put(rbd_dev); } static void rbd_dev_remove_parent(struct rbd_device *rbd_dev) -- 2.20.1