Commit d7952249 authored by Cunyin Chang's avatar Cunyin Chang Committed by Jim Harris
Browse files

iscsi: optimization for read process. 



This patch aimed at avoid run out of large rbuf for read commands.

Change-Id: If10f45292da5d5a26c2e338f1ddeafccedb88a4c
Signed-off-by: default avatarCunyin Chang <cunyin.chang@intel.com>
parent dfe5d837

lib/iscsi/conn.c

+6 −9
Original line number Diff line number Diff line
@@ -1093,17 +1093,14 @@ spdk_iscsi_conn_flush_pdus_internal(struct spdk_iscsi_conn *conn) 
						  tailq);

			} else {

				if (pdu->task) {

					if (pdu->bhs.opcode == ISCSI_OP_SCSI_DATAIN) {

						if (pdu->task->scsi.offset > 0) {

					if (pdu->bhs.opcode == ISCSI_OP_SCSI_DATAIN &&

					    pdu->task->scsi.length > SPDK_BDEV_SMALL_RBUF_MAX_SIZE) {

						conn->data_in_cnt--;

						if (pdu->bhs.flags & ISCSI_DATAIN_STATUS) {

							spdk_iscsi_task_put(spdk_iscsi_task_get_primary(pdu->task));

						}

						spdk_iscsi_conn_handle_queued_tasks(conn);

					}



						spdk_iscsi_conn_handle_queued_datain(conn);

					}



					spdk_iscsi_task_put(pdu->task);

				}

				spdk_put_pdu(pdu);

lib/iscsi/iscsi.c

+16 −12
Original line number Diff line number Diff line
@@ -2846,15 +2846,21 @@ static void spdk_iscsi_queue_mgmt_task(struct spdk_iscsi_conn *conn, 
	spdk_scsi_dev_queue_mgmt_task(conn->dev, &task->scsi);

}



int spdk_iscsi_conn_handle_queued_datain(struct spdk_iscsi_conn *conn)

int spdk_iscsi_conn_handle_queued_tasks(struct spdk_iscsi_conn *conn)

{

	struct spdk_iscsi_task *task;



	while (!TAILQ_EMPTY(&conn->queued_datain_tasks) &&

	       conn->data_in_cnt < MAX_EXTRA_DATAIN_PER_CONNECTION) {

	       conn->data_in_cnt < MAX_LARGE_DATAIN_PER_CONNECTION) {

		task = TAILQ_FIRST(&conn->queued_datain_tasks);

		assert(task->current_datain_offset <= task->scsi.transfer_len);



		if (task->current_datain_offset == 0) {

			task->current_datain_offset = task->scsi.length;

			conn->data_in_cnt++;

			spdk_iscsi_queue_task(conn, task);

			continue;

		}

		if (task->current_datain_offset < task->scsi.transfer_len) {

			struct spdk_iscsi_task *subtask;

			uint32_t remaining_size = 0;
@@ -2879,24 +2885,22 @@ int spdk_iscsi_conn_handle_queued_datain(struct spdk_iscsi_conn *conn) 
static int spdk_iscsi_op_scsi_read(struct spdk_iscsi_conn *conn,

				   struct spdk_iscsi_task *task)

{

	int32_t remaining_size = 0;



	TAILQ_INIT(&task->scsi.subtask_list);

	task->scsi.dxfer_dir = SPDK_SCSI_DIR_FROM_DEV;

	task->scsi.parent = NULL;

	task->scsi.offset = 0;

	task->scsi.length = DMIN32(SPDK_BDEV_LARGE_RBUF_MAX_SIZE, task->scsi.transfer_len);

	task->scsi.rbuf = NULL;

	spdk_iscsi_queue_task(conn, task);

	task->current_datain_offset = 0;



	remaining_size = task->scsi.transfer_len - task->scsi.length;

	task->current_datain_offset = task->scsi.length;

	if (task->scsi.transfer_len <= SPDK_BDEV_SMALL_RBUF_MAX_SIZE) {

		spdk_iscsi_queue_task(conn, task);

		return 0;

	}



	if (remaining_size > 0) {

	TAILQ_INSERT_TAIL(&conn->queued_datain_tasks, task, link);

		return spdk_iscsi_conn_handle_queued_datain(conn);

	}

	return 0;



	return spdk_iscsi_conn_handle_queued_tasks(conn);

}



static int

lib/iscsi/iscsi.h

+5 −6
Original line number Diff line number Diff line
@@ -107,13 +107,12 @@ 


/*

 * Defines maximum number of data in buffers each connection can have in

 *  use at any given time.  An "extra data in buffer" means any buffer after

 *  the first for the iSCSI I/O command.  So this limit does not affect I/O

 *  smaller than SPDK_ISCSI_MAX_SEND_DATA_SEGMENT_LENGTH.

 *  use at any given time. So this limit does not affect I/O smaller than

 *  SPDK_BDEV_SMALL_RBUF_MAX_SIZE.

 */

#define MAX_EXTRA_DATAIN_PER_CONNECTION 64

#define MAX_LARGE_DATAIN_PER_CONNECTION 64



#define NUM_PDU_PER_CONNECTION	(2 * (SPDK_ISCSI_MAX_QUEUE_DEPTH + MAX_EXTRA_DATAIN_PER_CONNECTION + 8))

#define NUM_PDU_PER_CONNECTION	(2 * (SPDK_ISCSI_MAX_QUEUE_DEPTH + MAX_LARGE_DATAIN_PER_CONNECTION + 8))



#define SPDK_ISCSI_MAX_BURST_LENGTH	\

		(SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH * MAX_DATA_OUT_PER_CONNECTION)
@@ -358,7 +357,7 @@ void process_task_mgmt_completion(spdk_event_t event); 
/* Memory management */

void spdk_put_pdu(struct spdk_iscsi_pdu *pdu);

struct spdk_iscsi_pdu *spdk_get_pdu(void);

int spdk_iscsi_conn_handle_queued_datain(struct spdk_iscsi_conn *conn);

int spdk_iscsi_conn_handle_queued_tasks(struct spdk_iscsi_conn *conn);



static inline int

spdk_get_immediate_data_buffer_size(void)