Since scsi_dh_activate() has become an asynchronous function, we do not need a workqueue for submitting scsi_dh_activate(). This patch just removes the workqueue that submits scsi_dh_activate(). --------- Signed-off-by: Chandra Seetharaman <sekharan@xxxxxxxxxx> --- drivers/md/dm-mpath.c | 51 ++++---------------------------------------------- 1 file changed, 4 insertions(+), 47 deletions(-) Index: linux-2.6.29/drivers/md/dm-mpath.c =================================================================== --- linux-2.6.29.orig/drivers/md/dm-mpath.c +++ linux-2.6.29/drivers/md/dm-mpath.c @@ -64,8 +64,6 @@ struct multipath { spinlock_t lock; const char *hw_handler_name; - struct work_struct activate_path; - struct pgpath *pgpath_to_activate; unsigned nr_priority_groups; struct list_head priority_groups; unsigned pg_init_required; /* pg_init needs calling? */ @@ -110,11 +108,11 @@ typedef int (*action_fn) (struct pgpath static struct kmem_cache *_mpio_cache; -static struct workqueue_struct *kmultipathd, *kmpath_handlerd; +static struct workqueue_struct *kmultipathd; static void process_queued_ios(struct work_struct *work); static void trigger_event(struct work_struct *work); -static void activate_path(struct work_struct *work); static void deactivate_path(struct work_struct *work); +static void pg_init_done(void *path, int errors); /*----------------------------------------------- @@ -160,7 +158,6 @@ static struct priority_group *alloc_prio static void free_pgpaths(struct list_head *pgpaths, struct dm_target *ti) { - unsigned long flags; struct pgpath *pgpath, *tmp; struct multipath *m = ti->private; @@ -169,10 +166,6 @@ static void free_pgpaths(struct list_hea if (m->hw_handler_name) scsi_dh_detach(bdev_get_queue(pgpath->path.dev->bdev)); dm_put_device(ti, pgpath->path.dev); - spin_lock_irqsave(&m->lock, flags); - if (m->pgpath_to_activate == pgpath) - m->pgpath_to_activate = NULL; - spin_unlock_irqrestore(&m->lock, flags); free_pgpath(pgpath); } } @@ -202,7 +195,6 @@ static struct multipath *alloc_multipath m->queue_io = 1; INIT_WORK(&m->process_queued_ios, process_queued_ios); INIT_WORK(&m->trigger_event, trigger_event); - INIT_WORK(&m->activate_path, activate_path); m->mpio_pool = mempool_create_slab_pool(MIN_IOS, _mpio_cache); if (!m->mpio_pool) { kfree(m); @@ -446,7 +438,6 @@ static void process_queued_ios(struct wo must_queue = 0; if (m->pg_init_required && !m->pg_init_in_progress && pgpath) { - m->pgpath_to_activate = pgpath; m->pg_init_count++; m->pg_init_required = 0; m->pg_init_in_progress = 1; @@ -457,7 +448,8 @@ out: spin_unlock_irqrestore(&m->lock, flags); if (init_required) - queue_work(kmpath_handlerd, &m->activate_path); + scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev), + pg_init_done, &pgpath->path); if (!must_queue) dispatch_queued_ios(m); @@ -834,7 +826,6 @@ static void multipath_dtr(struct dm_targ { struct multipath *m = (struct multipath *) ti->private; - flush_workqueue(kmpath_handlerd); flush_workqueue(kmultipathd); free_multipath(m); } @@ -1116,24 +1107,6 @@ static void pg_init_done(void *data, int spin_unlock_irqrestore(&m->lock, flags); } -static void activate_path(struct work_struct *work) -{ - int ret; - struct multipath *m = - container_of(work, struct multipath, activate_path); - struct dm_path *path; - unsigned long flags; - - spin_lock_irqsave(&m->lock, flags); - path = &m->pgpath_to_activate->path; - m->pgpath_to_activate = NULL; - spin_unlock_irqrestore(&m->lock, flags); - if (!path) - return; - ret = scsi_dh_activate(bdev_get_queue(path->dev->bdev), - pg_init_done, path); -} - /* * end_io handling */ @@ -1471,21 +1444,6 @@ static int __init dm_multipath_init(void return -ENOMEM; } - /* - * A separate workqueue is used to handle the device handlers - * to avoid overloading existing workqueue. Overloading the - * old workqueue would also create a bottleneck in the - * path of the storage hardware device activation. - */ - kmpath_handlerd = create_singlethread_workqueue("kmpath_handlerd"); - if (!kmpath_handlerd) { - DMERR("failed to create workqueue kmpath_handlerd"); - destroy_workqueue(kmultipathd); - dm_unregister_target(&multipath_target); - kmem_cache_destroy(_mpio_cache); - return -ENOMEM; - } - DMINFO("version %u.%u.%u loaded", multipath_target.version[0], multipath_target.version[1], multipath_target.version[2]); @@ -1495,7 +1453,6 @@ static int __init dm_multipath_init(void static void __exit dm_multipath_exit(void) { - destroy_workqueue(kmpath_handlerd); destroy_workqueue(kmultipathd); dm_unregister_target(&multipath_target); -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel