isci: preallocate requests

the dma_pool interface is optimized for object_size << page_size which
is not the case with isci_request objects and the dma_pool routines show
up in the top of the profile.

The old io_request_table which tracked whether tci slots were in-flight
or not is replaced with an IREQ_ACTIVE flag per request.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/scsi/isci/host.c

@@ -255,14 +255,14 @@ static bool scic_sds_controller_error_isr(struct scic_sds_controller *scic)
 static void scic_sds_controller_task_completion(struct scic_sds_controller *scic,
 						u32 completion_entry)
 {
-	u32 index;
-	struct scic_sds_request *sci_req;
-
-	index = SCU_GET_COMPLETION_INDEX(completion_entry);
-	sci_req = scic->io_request_table[index];
+	u32 index = SCU_GET_COMPLETION_INDEX(completion_entry);
+	struct isci_host *ihost = scic_to_ihost(scic);
+	struct isci_request *ireq = ihost->reqs[index];
+	struct scic_sds_request *sci_req = &ireq->sci;
 
 	/* Make sure that we really want to process this IO request */
-	if (sci_req && sci_req->io_tag != SCI_CONTROLLER_INVALID_IO_TAG &&
+	if (test_bit(IREQ_ACTIVE, &ireq->flags) &&
+	    sci_req->io_tag != SCI_CONTROLLER_INVALID_IO_TAG &&
 	    ISCI_TAG_SEQ(sci_req->io_tag) == scic->io_request_sequence[index])
 		/* Yep this is a valid io request pass it along to the io request handler */
 		scic_sds_io_request_tc_completion(sci_req, completion_entry);
@@ -280,7 +280,7 @@ static void scic_sds_controller_sdma_completion(struct scic_sds_controller *scic
 	switch (scu_get_command_request_type(completion_entry)) {
 	case SCU_CONTEXT_COMMAND_REQUEST_TYPE_POST_TC:
 	case SCU_CONTEXT_COMMAND_REQUEST_TYPE_DUMP_TC:
-		io_request = scic->io_request_table[index];
+		io_request = &scic_to_ihost(scic)->reqs[index]->sci;
 		dev_warn(scic_to_dev(scic),
 			 "%s: SCIC SDS Completion type SDMA %x for io request "
 			 "%p\n",
@@ -418,7 +418,7 @@ static void scic_sds_controller_event_completion(struct scic_sds_controller *sci
 		break;
 
 	case SCU_EVENT_TYPE_TRANSPORT_ERROR:
-		io_request = scic->io_request_table[index];
+		io_request = &ihost->reqs[index]->sci;
 		scic_sds_io_request_event_handler(io_request, completion_entry);
 		break;
 
@@ -426,7 +426,7 @@ static void scic_sds_controller_event_completion(struct scic_sds_controller *sci
 		switch (scu_get_event_specifier(completion_entry)) {
 		case SCU_EVENT_SPECIFIC_SMP_RESPONSE_NO_PE:
 		case SCU_EVENT_SPECIFIC_TASK_TIMEOUT:
-			io_request = scic->io_request_table[index];
+			io_request = &ihost->reqs[index]->sci;
 			if (io_request != NULL)
 				scic_sds_io_request_event_handler(io_request, completion_entry);
 			else
@@ -1187,9 +1187,6 @@ static void isci_host_completion_routine(unsigned long data)
 		spin_lock_irq(&isci_host->scic_lock);
 		isci_free_tag(isci_host, request->sci.io_tag);
 		spin_unlock_irq(&isci_host->scic_lock);
-
-		/* Free the request object. */
-		isci_request_free(isci_host, request);
 	}
 	list_for_each_entry_safe(request, next_request, &errored_request_list,
 				 completed_node) {
@@ -1227,9 +1224,6 @@ static void isci_host_completion_routine(unsigned long data)
 			list_del_init(&request->dev_node);
 			isci_free_tag(isci_host, request->sci.io_tag);
 			spin_unlock_irq(&isci_host->scic_lock);
-
-			/* Free the request object. */
-			isci_request_free(isci_host, request);
 		}
 	}
 
@@ -2469,13 +2463,6 @@ int isci_host_init(struct isci_host *isci_host)
 	if (err)
 		return err;
 
-	isci_host->dma_pool = dmam_pool_create(DRV_NAME, &isci_host->pdev->dev,
-					       sizeof(struct isci_request),
-					       SLAB_HWCACHE_ALIGN, 0);
-
-	if (!isci_host->dma_pool)
-		return -ENOMEM;
-
 	for (i = 0; i < SCI_MAX_PORTS; i++)
 		isci_port_init(&isci_host->ports[i], isci_host, i);
 
@@ -2489,6 +2476,25 @@ int isci_host_init(struct isci_host *isci_host)
 		INIT_LIST_HEAD(&idev->node);
 	}
 
+	for (i = 0; i < SCI_MAX_IO_REQUESTS; i++) {
+		struct isci_request *ireq;
+		dma_addr_t dma;
+
+		ireq = dmam_alloc_coherent(&isci_host->pdev->dev,
+					   sizeof(struct isci_request), &dma,
+					   GFP_KERNEL);
+		if (!ireq)
+			return -ENOMEM;
+
+		ireq->sci.tc = &isci_host->sci.task_context_table[i];
+		ireq->sci.owning_controller = &isci_host->sci;
+		spin_lock_init(&ireq->state_lock);
+		ireq->request_daddr = dma;
+		ireq->isci_host = isci_host;
+
+		isci_host->reqs[i] = ireq;
+	}
+
 	return 0;
 }
 
@@ -2602,12 +2608,13 @@ struct scic_sds_request *scic_request_by_tag(struct scic_sds_controller *scic, u
 	task_index = ISCI_TAG_TCI(io_tag);
 
 	if (task_index < scic->task_context_entries) {
-		if (scic->io_request_table[task_index] != NULL) {
+		struct isci_request *ireq = scic_to_ihost(scic)->reqs[task_index];
+
+		if (test_bit(IREQ_ACTIVE, &ireq->flags)) {
 			task_sequence = ISCI_TAG_SEQ(io_tag);
 
-			if (task_sequence == scic->io_request_sequence[task_index]) {
-				return scic->io_request_table[task_index];
-			}
+			if (task_sequence == scic->io_request_sequence[task_index])
+				return &ireq->sci;
 		}
 	}
 
@@ -2820,7 +2827,7 @@ enum sci_status scic_controller_start_io(struct scic_sds_controller *scic,
 	if (status != SCI_SUCCESS)
 		return status;
 
-	scic->io_request_table[ISCI_TAG_TCI(req->io_tag)] = req;
+	set_bit(IREQ_ACTIVE, &sci_req_to_ireq(req)->flags);
 	scic_sds_controller_post_request(scic, scic_sds_request_get_post_context(req));
 	return SCI_SUCCESS;
 }
@@ -2897,7 +2904,7 @@ enum sci_status scic_controller_complete_io(
 			return status;
 
 		index = ISCI_TAG_TCI(request->io_tag);
-		scic->io_request_table[index] = NULL;
+		clear_bit(IREQ_ACTIVE, &sci_req_to_ireq(request)->flags);
 		return SCI_SUCCESS;
 	default:
 		dev_warn(scic_to_dev(scic), "invalid state to complete I/O");
@@ -2915,7 +2922,7 @@ enum sci_status scic_controller_continue_io(struct scic_sds_request *sci_req)
 		return SCI_FAILURE_INVALID_STATE;
 	}
 
-	scic->io_request_table[ISCI_TAG_TCI(sci_req->io_tag)] = sci_req;
+	set_bit(IREQ_ACTIVE, &sci_req_to_ireq(sci_req)->flags);
 	scic_sds_controller_post_request(scic, scic_sds_request_get_post_context(sci_req));
 	return SCI_SUCCESS;
 }
@@ -2934,6 +2941,7 @@ enum sci_task_status scic_controller_start_task(
 	struct scic_sds_remote_device *rdev,
 	struct scic_sds_request *req)
 {
+	struct isci_request *ireq = sci_req_to_ireq(req);
 	enum sci_status status;
 
 	if (scic->sm.current_state_id != SCIC_READY) {
@@ -2947,7 +2955,7 @@ enum sci_task_status scic_controller_start_task(
 	status = scic_sds_remote_device_start_task(scic, rdev, req);
 	switch (status) {
 	case SCI_FAILURE_RESET_DEVICE_PARTIAL_SUCCESS:
-		scic->io_request_table[ISCI_TAG_TCI(req->io_tag)] = req;
+		set_bit(IREQ_ACTIVE, &ireq->flags);
 
 		/*
 		 * We will let framework know this task request started successfully,
@@ -2956,7 +2964,7 @@ enum sci_task_status scic_controller_start_task(
 		 */
 		return SCI_SUCCESS;
 	case SCI_SUCCESS:
-		scic->io_request_table[ISCI_TAG_TCI(req->io_tag)] = req;
+		set_bit(IREQ_ACTIVE, &ireq->flags);
 
 		scic_sds_controller_post_request(scic,
 			scic_sds_request_get_post_context(req));

drivers/scsi/isci/host.h

@@ -165,14 +165,6 @@ struct scic_sds_controller {
 	 */
 	struct scic_sds_remote_device *device_table[SCI_MAX_REMOTE_DEVICES];
 
-	/**
-	 * This field is the array of IO request objects that are currently active for
-	 * this controller object.  This table is used as a fast lookup of the io
-	 * request object that need to handle completion queue notifications.  The
-	 * table is TCi based.
-	 */
-	struct scic_sds_request *io_request_table[SCI_MAX_IO_REQUESTS];
-
 	/**
 	 * This field is the free RNi data structure
 	 */
@@ -298,7 +290,6 @@ struct isci_host {
 	union scic_oem_parameters oem_parameters;
 
 	int id; /* unique within a given pci device */
-	struct dma_pool *dma_pool;
 	struct isci_phy phys[SCI_MAX_PHYS];
 	struct isci_port ports[SCI_MAX_PORTS + 1]; /* includes dummy port */
 	struct sas_ha_struct sas_ha;
@@ -315,7 +306,7 @@ struct isci_host {
 	struct list_head requests_to_complete;
 	struct list_head requests_to_errorback;
 	spinlock_t scic_lock;
-
+	struct isci_request *reqs[SCI_MAX_IO_REQUESTS];
 	struct isci_remote_device devices[SCI_MAX_REMOTE_DEVICES];
 };
 

drivers/scsi/isci/remote_device.c

@@ -136,16 +136,19 @@ static void rnc_destruct_done(void *_dev)
 static enum sci_status scic_sds_remote_device_terminate_requests(struct scic_sds_remote_device *sci_dev)
 {
 	struct scic_sds_controller *scic = sci_dev->owning_port->owning_controller;
+	struct isci_host *ihost = scic_to_ihost(scic);
 	u32 i, request_count = sci_dev->started_request_count;
 	enum sci_status status  = SCI_SUCCESS;
 
 	for (i = 0; i < SCI_MAX_IO_REQUESTS && i < request_count; i++) {
-		struct scic_sds_request *sci_req;
+		struct isci_request *ireq = ihost->reqs[i];
+		struct scic_sds_request *sci_req = &ireq->sci;
 		enum sci_status s;
 
-		sci_req = scic->io_request_table[i];
-		if (!sci_req || sci_req->target_device != sci_dev)
+		if (!test_bit(IREQ_ACTIVE, &ireq->flags) ||
+		    sci_req->target_device != sci_dev)
 			continue;
+
 		s = scic_controller_terminate_request(scic, sci_dev, sci_req);
 		if (s != SCI_SUCCESS)
 			status = s;

drivers/scsi/isci/request.c

@@ -3017,13 +3017,10 @@ static const struct sci_base_state scic_sds_request_state_table[] = {
 static void
 scic_sds_general_request_construct(struct scic_sds_controller *scic,
 				   struct scic_sds_remote_device *sci_dev,
-				   u16 io_tag,
 				   struct scic_sds_request *sci_req)
 {
 	sci_init_sm(&sci_req->sm, scic_sds_request_state_table, SCI_REQ_INIT);
 
-	sci_req->io_tag = io_tag;
-	sci_req->owning_controller = scic;
 	sci_req->target_device = sci_dev;
 	sci_req->protocol = SCIC_NO_PROTOCOL;
 	sci_req->saved_rx_frame_index = SCU_INVALID_FRAME_INDEX;
@@ -3031,20 +3028,18 @@ scic_sds_general_request_construct(struct scic_sds_controller *scic,
 	sci_req->sci_status   = SCI_SUCCESS;
 	sci_req->scu_status   = 0;
 	sci_req->post_context = 0xFFFFFFFF;
-	sci_req->tc = &scic->task_context_table[ISCI_TAG_TCI(io_tag)];
-	WARN_ONCE(io_tag == SCI_CONTROLLER_INVALID_IO_TAG, "straggling invalid tag usage\n");
 }
 
 static enum sci_status
 scic_io_request_construct(struct scic_sds_controller *scic,
 			  struct scic_sds_remote_device *sci_dev,
-			  u16 io_tag, struct scic_sds_request *sci_req)
+			  struct scic_sds_request *sci_req)
 {
 	struct domain_device *dev = sci_dev_to_domain(sci_dev);
 	enum sci_status status = SCI_SUCCESS;
 
 	/* Build the common part of the request */
-	scic_sds_general_request_construct(scic, sci_dev, io_tag, sci_req);
+	scic_sds_general_request_construct(scic, sci_dev, sci_req);
 
 	if (sci_dev->rnc.remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
 		return SCI_FAILURE_INVALID_REMOTE_DEVICE;
@@ -3071,7 +3066,7 @@ enum sci_status scic_task_request_construct(struct scic_sds_controller *scic,
 	enum sci_status status = SCI_SUCCESS;
 
 	/* Build the common part of the request */
-	scic_sds_general_request_construct(scic, sci_dev, io_tag, sci_req);
+	scic_sds_general_request_construct(scic, sci_dev, sci_req);
 
 	if (dev->dev_type == SAS_END_DEV ||
 	    dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) {
@@ -3291,8 +3286,7 @@ static enum sci_status isci_smp_request_build(struct isci_request *ireq)
  */
 static enum sci_status isci_io_request_build(struct isci_host *isci_host,
 					     struct isci_request *request,
-					     struct isci_remote_device *isci_device,
-					     u16 tag)
+					     struct isci_remote_device *isci_device)
 {
 	enum sci_status status = SCI_SUCCESS;
 	struct sas_task *task = isci_request_access_task(request);
@@ -3325,11 +3319,8 @@ static enum sci_status isci_io_request_build(struct isci_host *isci_host,
 			return SCI_FAILURE_INSUFFICIENT_RESOURCES;
 	}
 
-	/* build the common request object. For now,
-	 * we will let the core allocate the IO tag.
-	 */
 	status = scic_io_request_construct(&isci_host->sci, sci_device,
-					   tag, &request->sci);
+					   &request->sci);
 
 	if (status != SCI_SUCCESS) {
 		dev_warn(&isci_host->pdev->dev,
@@ -3359,65 +3350,51 @@ static enum sci_status isci_io_request_build(struct isci_host *isci_host,
 	return SCI_SUCCESS;
 }
 
-static struct isci_request *isci_request_alloc_core(struct isci_host *ihost,
-						    gfp_t gfp_flags)
+static struct isci_request *isci_request_from_tag(struct isci_host *ihost, u16 tag)
 {
-	dma_addr_t handle;
 	struct isci_request *ireq;
 
-	ireq = dma_pool_alloc(ihost->dma_pool, gfp_flags, &handle);
-	if (!ireq) {
-		dev_warn(&ihost->pdev->dev,
-			 "%s: dma_pool_alloc returned NULL\n", __func__);
-		return NULL;
-	}
-
-	/* initialize the request object.	*/
-	spin_lock_init(&ireq->state_lock);
-	ireq->request_daddr = handle;
-	ireq->isci_host = ihost;
+	ireq = ihost->reqs[ISCI_TAG_TCI(tag)];
+	ireq->sci.io_tag = tag;
 	ireq->io_request_completion = NULL;
 	ireq->flags = 0;
 	ireq->num_sg_entries = 0;
 	INIT_LIST_HEAD(&ireq->completed_node);
 	INIT_LIST_HEAD(&ireq->dev_node);
-
 	isci_request_change_state(ireq, allocated);
 
 	return ireq;
 }
 
-static struct isci_request *isci_request_alloc_io(struct isci_host *ihost,
+static struct isci_request *isci_io_request_from_tag(struct isci_host *ihost,
 						     struct sas_task *task,
-						  gfp_t gfp_flags)
+						     u16 tag)
 {
 	struct isci_request *ireq;
 
-	ireq = isci_request_alloc_core(ihost, gfp_flags);
-	if (ireq) {
+	ireq = isci_request_from_tag(ihost, tag);
 	ireq->ttype_ptr.io_task_ptr = task;
 	ireq->ttype = io_task;
 	task->lldd_task = ireq;
-	}
+
 	return ireq;
 }
 
-struct isci_request *isci_request_alloc_tmf(struct isci_host *ihost,
+struct isci_request *isci_tmf_request_from_tag(struct isci_host *ihost,
 					       struct isci_tmf *isci_tmf,
-					    gfp_t gfp_flags)
+					       u16 tag)
 {
 	struct isci_request *ireq;
 
-	ireq = isci_request_alloc_core(ihost, gfp_flags);
-	if (ireq) {
+	ireq = isci_request_from_tag(ihost, tag);
 	ireq->ttype_ptr.tmf_task_ptr = isci_tmf;
 	ireq->ttype = tmf_task;
-	}
+
 	return ireq;
 }
 
 int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *idev,
-			 struct sas_task *task, u16 tag, gfp_t gfp_flags)
+			 struct sas_task *task, u16 tag)
 {
 	enum sci_status status = SCI_FAILURE_UNSUPPORTED_PROTOCOL;
 	struct isci_request *ireq;
@@ -3425,17 +3402,15 @@ int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *ide
 	int ret = 0;
 
 	/* do common allocation and init of request object. */
-	ireq = isci_request_alloc_io(ihost, task, gfp_flags);
-	if (!ireq)
-		goto out;
+	ireq = isci_io_request_from_tag(ihost, task, tag);
 
-	status = isci_io_request_build(ihost, ireq, idev, tag);
+	status = isci_io_request_build(ihost, ireq, idev);
 	if (status != SCI_SUCCESS) {
 		dev_warn(&ihost->pdev->dev,
 			 "%s: request_construct failed - status = 0x%x\n",
 			 __func__,
 			 status);
-		goto out;
+		return status;
 	}
 
 	spin_lock_irqsave(&ihost->scic_lock, flags);
@@ -3468,7 +3443,7 @@ int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *ide
 			 "%s: failed request start (0x%x)\n",
 			 __func__, status);
 		spin_unlock_irqrestore(&ihost->scic_lock, flags);
-		goto out;
+		return status;
 	}
 
 	/* Either I/O started OK, or the core has signaled that
@@ -3518,13 +3493,5 @@ int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *ide
 		status = SCI_SUCCESS;
 	}
 
- out:
-	if (status != SCI_SUCCESS) {
-		/* release dma memory on failure. */
-		isci_request_free(ihost, ireq);
-		ireq = NULL;
-		ret = SCI_FAILURE;
-	}
-
 	return ret;
 }

drivers/scsi/isci/request.h

@@ -257,6 +257,7 @@ struct isci_request {
 	#define IREQ_COMPLETE_IN_TARGET 0
 	#define IREQ_TERMINATED 1
 	#define IREQ_TMF 2
+	#define IREQ_ACTIVE 3
 	unsigned long flags;
 
 	union ttype_ptr_union {
@@ -590,33 +591,16 @@ isci_request_change_started_to_aborted(struct isci_request *isci_request,
 						       completion_ptr,
 						       aborted);
 }
-/**
- * isci_request_free() - This function frees the request object.
- * @isci_host: This parameter specifies the ISCI host object
- * @isci_request: This parameter points to the isci_request object
- *
- */
-static inline void isci_request_free(struct isci_host *isci_host,
-				     struct isci_request *isci_request)
-{
-	if (!isci_request)
-		return;
-
-	/* release the dma memory if we fail. */
-	dma_pool_free(isci_host->dma_pool,
-		      isci_request,
-		      isci_request->request_daddr);
-}
 
 #define isci_request_access_task(req) ((req)->ttype_ptr.io_task_ptr)
 
 #define isci_request_access_tmf(req) ((req)->ttype_ptr.tmf_task_ptr)
 
-struct isci_request *isci_request_alloc_tmf(struct isci_host *ihost,
+struct isci_request *isci_tmf_request_from_tag(struct isci_host *ihost,
 					       struct isci_tmf *isci_tmf,
-					    gfp_t gfp_flags);
+					       u16 tag);
 int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *idev,
-			 struct sas_task *task, u16 tag, gfp_t gfp_flags);
+			 struct sas_task *task, u16 tag);
 void isci_terminate_pending_requests(struct isci_host *ihost,
 				     struct isci_remote_device *idev);
 enum sci_status

drivers/scsi/isci/task.c

@@ -203,7 +203,7 @@ int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags)
 				spin_unlock_irqrestore(&task->task_state_lock, flags);
 
 				/* build and send the request. */
-				status = isci_request_execute(ihost, idev, task, tag, gfp_flags);
+				status = isci_request_execute(ihost, idev, task, tag);
 
 				if (status != SCI_SUCCESS) {
 
@@ -252,7 +252,7 @@ static struct isci_request *isci_task_request_build(struct isci_host *ihost,
 	dev = idev->domain_dev;
 
 	/* do common allocation and init of request object. */
-	ireq = isci_request_alloc_tmf(ihost, isci_tmf, GFP_ATOMIC);
+	ireq = isci_tmf_request_from_tag(ihost, isci_tmf, tag);
 	if (!ireq)
 		return NULL;
 
@@ -266,7 +266,7 @@ static struct isci_request *isci_task_request_build(struct isci_host *ihost,
 			 "status = 0x%x\n",
 			 __func__,
 			 status);
-		goto errout;
+		return NULL;
 	}
 
 	/* XXX convert to get this from task->tproto like other drivers */
@@ -274,7 +274,7 @@ static struct isci_request *isci_task_request_build(struct isci_host *ihost,
 		isci_tmf->proto = SAS_PROTOCOL_SSP;
 		status = scic_task_request_construct_ssp(&ireq->sci);
 		if (status != SCI_SUCCESS)
-			goto errout;
+			return NULL;
 	}
 
 	if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) {
@@ -282,12 +282,9 @@ static struct isci_request *isci_task_request_build(struct isci_host *ihost,
 		status = isci_sata_management_task_request_build(ireq);
 
 		if (status != SCI_SUCCESS)
-			goto errout;
+			return NULL;
 	}
 	return ireq;
- errout:
-	isci_request_free(ihost, ireq);
-	return NULL;
 }
 
 int isci_task_execute_tmf(struct isci_host *ihost,
@@ -349,7 +346,7 @@ int isci_task_execute_tmf(struct isci_host *ihost,
 			 status,
 			 ireq);
 		spin_unlock_irqrestore(&ihost->scic_lock, flags);
-		goto err_ireq;
+		goto err_tci;
 	}
 
 	if (tmf->cb_state_func != NULL)
@@ -401,8 +398,6 @@ int isci_task_execute_tmf(struct isci_host *ihost,
 
 	return ret;
 
- err_ireq:
-	isci_request_free(ihost, ireq);
  err_tci:
 	spin_lock_irqsave(&ihost->scic_lock, flags);
 	isci_tci_free(ihost, ISCI_TAG_TCI(tag));
@@ -516,8 +511,6 @@ static void isci_request_cleanup_completed_loiterer(
 		spin_lock_irqsave(&isci_host->scic_lock, flags);
 		list_del_init(&isci_request->dev_node);
 		spin_unlock_irqrestore(&isci_host->scic_lock, flags);
-
-		isci_request_free(isci_host, isci_request);
 	}
 }