scsi: scsi_debug: mq_poll support (c4b57d89) · Commits · EulixOS / Software / Kernel

drivers/scsi/scsi_debug.c

+130 −0

Original line number	Diff line number	Diff line
		@@ -829,6 +829,7 @@ static int sdeb_zbc_max_open = DEF_ZBC_MAX_OPEN_ZONES;
		static int sdeb_zbc_nr_conv = DEF_ZBC_NR_CONV_ZONES;

		static int submit_queues = DEF_SUBMIT_QUEUES; /* > 1 for multi-queue (mq) */
		static int poll_queues; /* iouring iopoll interface.*/
		static struct sdebug_queue sdebug_q_arr; / ptr to array of submit queues */

		static DEFINE_RWLOCK(atomic_rw);
		@@ -5432,6 +5433,14 @@ static int schedule_resp(struct scsi_cmnd cmnd, struct sdebug_dev_info devip,
		cmnd->host_scribble = (unsigned char *)sqcp;
		sd_dp = sqcp->sd_dp;
		spin_unlock_irqrestore(&sqp->qc_lock, iflags);

		/* Do not complete IO from default completion path.
		* Let it to be on queue.
		* Completion should happen from mq_poll interface.
		*/
		if ((sqp - sdebug_q_arr) >= (submit_queues - poll_queues))
		return 0;

		if (!sd_dp) {
		sd_dp = kzalloc(sizeof(*sd_dp), GFP_ATOMIC);
		if (!sd_dp) {
		@@ -5615,6 +5624,7 @@ module_param_named(sector_size, sdebug_sector_size, int, S_IRUGO);
		module_param_named(statistics, sdebug_statistics, bool, S_IRUGO \| S_IWUSR);
		module_param_named(strict, sdebug_strict, bool, S_IRUGO \| S_IWUSR);
		module_param_named(submit_queues, submit_queues, int, S_IRUGO);
		module_param_named(poll_queues, poll_queues, int, S_IRUGO);
		module_param_named(tur_ms_to_ready, sdeb_tur_ms_to_ready, int, S_IRUGO);
		module_param_named(unmap_alignment, sdebug_unmap_alignment, int, S_IRUGO);
		module_param_named(unmap_granularity, sdebug_unmap_granularity, int, S_IRUGO);
		@@ -5677,6 +5687,7 @@ MODULE_PARM_DESC(opt_xferlen_exp, "optimal transfer length granularity exponent
		MODULE_PARM_DESC(opts, "1->noise, 2->medium_err, 4->timeout, 8->recovered_err... (def=0)");
		MODULE_PARM_DESC(per_host_store, "If set, next positive add_host will get new store (def=0)");
		MODULE_PARM_DESC(physblk_exp, "physical block exponent (def=0)");
		MODULE_PARM_DESC(poll_queues, "support for iouring iopoll queues (1 to max(submit_queues - 1)");
		MODULE_PARM_DESC(ptype, "SCSI peripheral type(def=0[disk])");
		MODULE_PARM_DESC(random, "If set, uniformly randomize command duration between 0 and delay_in_ns");
		MODULE_PARM_DESC(removable, "claim to have removable media (def=0)");
		@@ -7202,6 +7213,104 @@ static int resp_not_ready(struct scsi_cmnd scp, struct sdebug_dev_info devip)
		return check_condition_result;
		}

		static int sdebug_map_queues(struct Scsi_Host *shost)
		{
		int i, qoff;

		if (shost->nr_hw_queues == 1)
		return 0;

		for (i = 0, qoff = 0; i < HCTX_MAX_TYPES; i++) {
		struct blk_mq_queue_map *map = &shost->tag_set.map[i];

		map->nr_queues = 0;

		if (i == HCTX_TYPE_DEFAULT)
		map->nr_queues = submit_queues - poll_queues;
		else if (i == HCTX_TYPE_POLL)
		map->nr_queues = poll_queues;

		if (!map->nr_queues) {
		BUG_ON(i == HCTX_TYPE_DEFAULT);
		continue;
		}

		map->queue_offset = qoff;
		blk_mq_map_queues(map);

		qoff += map->nr_queues;
		}

		return 0;

		}

		static int sdebug_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
		{
		int qc_idx;
		int retiring = 0;
		unsigned long iflags;
		struct sdebug_queue *sqp;
		struct sdebug_queued_cmd *sqcp;
		struct scsi_cmnd *scp;
		struct sdebug_dev_info *devip;
		int num_entries = 0;

		sqp = sdebug_q_arr + queue_num;

		do {
		spin_lock_irqsave(&sqp->qc_lock, iflags);
		qc_idx = find_first_bit(sqp->in_use_bm, sdebug_max_queue);
		if (unlikely((qc_idx < 0) \|\| (qc_idx >= sdebug_max_queue)))
		goto out;

		sqcp = &sqp->qc_arr[qc_idx];
		scp = sqcp->a_cmnd;
		if (unlikely(scp == NULL)) {
		pr_err("scp is NULL, queue_num=%d, qc_idx=%d from %s\n",
		queue_num, qc_idx, __func__);
		goto out;
		}
		devip = (struct sdebug_dev_info *)scp->device->hostdata;
		if (likely(devip))
		atomic_dec(&devip->num_in_q);
		else
		pr_err("devip=NULL from %s\n", __func__);
		if (unlikely(atomic_read(&retired_max_queue) > 0))
		retiring = 1;

		sqcp->a_cmnd = NULL;
		if (unlikely(!test_and_clear_bit(qc_idx, sqp->in_use_bm))) {
		pr_err("Unexpected completion sqp %p queue_num=%d qc_idx=%d from %s\n",
		sqp, queue_num, qc_idx, __func__);
		goto out;
		}

		if (unlikely(retiring)) { /* user has reduced max_queue */
		int k, retval;

		retval = atomic_read(&retired_max_queue);
		if (qc_idx >= retval) {
		pr_err("index %d too large\n", retval);
		goto out;
		}
		k = find_last_bit(sqp->in_use_bm, retval);
		if ((k < sdebug_max_queue) \|\| (k == retval))
		atomic_set(&retired_max_queue, 0);
		else
		atomic_set(&retired_max_queue, k + 1);
		}
		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
		scp->scsi_done(scp); /* callback to mid level */
		num_entries++;
		} while (1);

		out:
		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
		return num_entries;
		}


		static int scsi_debug_queuecommand(struct Scsi_Host *shost,
		struct scsi_cmnd *scp)
		{
		@@ -7381,6 +7490,8 @@ static struct scsi_host_template sdebug_driver_template = {
		.ioctl = scsi_debug_ioctl,
		.queuecommand = scsi_debug_queuecommand,
		.change_queue_depth = sdebug_change_qdepth,
		.map_queues = sdebug_map_queues,
		.mq_poll = sdebug_blk_mq_poll,
		.eh_abort_handler = scsi_debug_abort,
		.eh_device_reset_handler = scsi_debug_device_reset,
		.eh_target_reset_handler = scsi_debug_target_reset,
		@@ -7428,6 +7539,25 @@ static int sdebug_driver_probe(struct device *dev)
		if (sdebug_host_max_queue)
		hpnt->host_tagset = 1;

		/* poll queues are possible for nr_hw_queues > 1 */
		if (hpnt->nr_hw_queues == 1 \|\| (poll_queues < 1)) {
		pr_warn("%s: trim poll_queues to 0. poll_q/nr_hw = (%d/%d)\n",
		my_name, poll_queues, hpnt->nr_hw_queues);
		poll_queues = 0;
		}

		/*
		* Poll queues don't need interrupts, but we need at least one I/O queue
		* left over for non-polled I/O.
		* If condition not met, trim poll_queues to 1 (just for simplicity).
		*/
		if (poll_queues >= submit_queues) {
		pr_warn("%s: trim poll_queues to 1\n", my_name);
		poll_queues = 1;
		}
		if (poll_queues)
		hpnt->nr_maps = 3;

		sdbg_host->shost = hpnt;
		((struct sdebug_host_info *)hpnt->hostdata) = sdbg_host;
		if ((hpnt->this_id >= 0) && (sdebug_num_tgts > hpnt->this_id))