block: kill request slab cache

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-core.c

@@ -57,11 +57,6 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(block_unplug);
 
 DEFINE_IDA(blk_queue_ida);
 
-/*
- * For the allocated request tables
- */
-struct kmem_cache *request_cachep;
-
 /*
  * For queue allocation
  */
@@ -1971,9 +1966,6 @@ int __init blk_dev_init(void)
 	if (!kblockd_workqueue)
 		panic("Failed to create kblockd\n");
 
-	request_cachep = kmem_cache_create("blkdev_requests",
-			sizeof(struct request), 0, SLAB_PANIC, NULL);
-
 	blk_requestq_cachep = kmem_cache_create("request_queue",
 			sizeof(struct request_queue), 0, SLAB_PANIC, NULL);
 

block/blk.h

@@ -32,7 +32,6 @@ struct blk_flush_queue {
 };
 
 extern struct kmem_cache *blk_requestq_cachep;
-extern struct kmem_cache *request_cachep;
 extern struct kobj_type blk_queue_ktype;
 extern struct ida blk_queue_ida;