From 8622384f138b786b9ae639e79ccfb84c7db82cbc Mon Sep 17 00:00:00 2001 From: Sebastian Ott Date: Fri, 5 Dec 2014 16:47:17 +0100 Subject: s390/scm_block: make the number of reqs per HW req configurable Introduce a module parameter to specify the number of requests we try to handle with one HW request. Suggested-by: Peter Oberparleiter Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky --- drivers/s390/block/scm_blk.c | 48 ++++++++++++++++++++++++++++++-------------- drivers/s390/block/scm_blk.h | 3 +-- 2 files changed, 34 insertions(+), 17 deletions(-) diff --git a/drivers/s390/block/scm_blk.c b/drivers/s390/block/scm_blk.c index cd27cb92ac6d..75d9896deccb 100644 --- a/drivers/s390/block/scm_blk.c +++ b/drivers/s390/block/scm_blk.c @@ -25,10 +25,14 @@ static mempool_t *aidaw_pool; static DEFINE_SPINLOCK(list_lock); static LIST_HEAD(inactive_requests); static unsigned int nr_requests = 64; +static unsigned int nr_requests_per_io = 8; static atomic_t nr_devices = ATOMIC_INIT(0); module_param(nr_requests, uint, S_IRUGO); MODULE_PARM_DESC(nr_requests, "Number of parallel requests."); +module_param(nr_requests_per_io, uint, S_IRUGO); +MODULE_PARM_DESC(nr_requests_per_io, "Number of requests per IO."); + MODULE_DESCRIPTION("Block driver for s390 storage class memory."); MODULE_LICENSE("GPL"); MODULE_ALIAS("scm:scmdev*"); @@ -39,6 +43,7 @@ static void __scm_free_rq(struct scm_request *scmrq) free_page((unsigned long) scmrq->aob); __scm_free_rq_cluster(scmrq); + kfree(scmrq->request); kfree(aobrq); } @@ -69,15 +74,16 @@ static int __scm_alloc_rq(void) scmrq = (void *) aobrq->data; scmrq->aob = (void *) get_zeroed_page(GFP_DMA); - if (!scmrq->aob) { - __scm_free_rq(scmrq); - return -ENOMEM; - } + if (!scmrq->aob) + goto free; - if (__scm_alloc_rq_cluster(scmrq)) { - __scm_free_rq(scmrq); - return -ENOMEM; - } + scmrq->request = kcalloc(nr_requests_per_io, sizeof(scmrq->request[0]), + GFP_KERNEL); + if (!scmrq->request) + goto free; + + if (__scm_alloc_rq_cluster(scmrq)) + goto free; INIT_LIST_HEAD(&scmrq->list); spin_lock_irq(&list_lock); @@ -85,6 +91,9 @@ static int __scm_alloc_rq(void) spin_unlock_irq(&list_lock); return 0; +free: + __scm_free_rq(scmrq); + return -ENOMEM; } static int scm_alloc_rqs(unsigned int nrqs) @@ -122,7 +131,7 @@ static void scm_request_done(struct scm_request *scmrq) u64 aidaw; int i; - for (i = 0; i < SCM_RQ_PER_IO && scmrq->request[i]; i++) { + for (i = 0; i < nr_requests_per_io && scmrq->request[i]; i++) { msb = &scmrq->aob->msb[i]; aidaw = msb->data_addr; @@ -214,7 +223,8 @@ static inline void scm_request_init(struct scm_blk_dev *bdev, struct aob_rq_header *aobrq = to_aobrq(scmrq); struct aob *aob = scmrq->aob; - memset(scmrq->request, 0, sizeof(scmrq->request)); + memset(scmrq->request, 0, + nr_requests_per_io * sizeof(scmrq->request[0])); memset(aob, 0, sizeof(*aob)); aobrq->scmdev = bdev->scmdev; aob->request.cmd_code = ARQB_CMD_MOVE; @@ -223,7 +233,7 @@ static inline void scm_request_init(struct scm_blk_dev *bdev, scmrq->retries = 4; scmrq->error = 0; /* We don't use all msbs - place aidaws at the end of the aob page. */ - scmrq->next_aidaw = (void *) &aob->msb[SCM_RQ_PER_IO]; + scmrq->next_aidaw = (void *) &aob->msb[nr_requests_per_io]; scm_request_cluster_init(scmrq); } @@ -242,7 +252,7 @@ void scm_request_requeue(struct scm_request *scmrq) int i; scm_release_cluster(scmrq); - for (i = 0; i < SCM_RQ_PER_IO && scmrq->request[i]; i++) + for (i = 0; i < nr_requests_per_io && scmrq->request[i]; i++) blk_requeue_request(bdev->rq, scmrq->request[i]); atomic_dec(&bdev->queued_reqs); @@ -256,7 +266,7 @@ void scm_request_finish(struct scm_request *scmrq) int i; scm_release_cluster(scmrq); - for (i = 0; i < SCM_RQ_PER_IO && scmrq->request[i]; i++) + for (i = 0; i < nr_requests_per_io && scmrq->request[i]; i++) blk_end_request_all(scmrq->request[i], scmrq->error); atomic_dec(&bdev->queued_reqs); @@ -342,7 +352,7 @@ static void scm_blk_request(struct request_queue *rq) } blk_start_request(req); - if (scmrq->aob->request.msb_count < SCM_RQ_PER_IO) + if (scmrq->aob->request.msb_count < nr_requests_per_io) continue; if (scm_request_start(scmrq)) @@ -551,11 +561,19 @@ void scm_blk_set_available(struct scm_blk_dev *bdev) spin_unlock_irqrestore(&bdev->lock, flags); } +static bool __init scm_blk_params_valid(void) +{ + if (!nr_requests_per_io || nr_requests_per_io > 64) + return false; + + return scm_cluster_size_valid(); +} + static int __init scm_blk_init(void) { int ret = -EINVAL; - if (!scm_cluster_size_valid()) + if (!scm_blk_params_valid()) goto out; ret = register_blkdev(0, "scm"); diff --git a/drivers/s390/block/scm_blk.h b/drivers/s390/block/scm_blk.h index 3dae0a3570ce..09218cdc5129 100644 --- a/drivers/s390/block/scm_blk.h +++ b/drivers/s390/block/scm_blk.h @@ -11,7 +11,6 @@ #include #define SCM_NR_PARTS 8 -#define SCM_RQ_PER_IO 8 #define SCM_QUEUE_DELAY 5 struct scm_blk_dev { @@ -32,7 +31,7 @@ struct scm_blk_dev { struct scm_request { struct scm_blk_dev *bdev; struct aidaw *next_aidaw; - struct request *request[SCM_RQ_PER_IO]; + struct request **request; struct aob *aob; struct list_head list; u8 retries; -- cgit v1.2.2