Message ID | 20201015133721.63476-1-kashyap.desai@broadcom.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | io_uring iopoll in scsi layer | expand |
> -----Original Message----- > From: Kashyap Desai [mailto:kashyap.desai@broadcom.com] > Sent: Thursday, October 15, 2020 7:07 PM > To: linux-scsi@vger.kernel.org > Cc: Kashyap Desai <kashyap.desai@broadcom.com>; dgilbert@interlog.com; > linux-block@vger.kernel.org > Subject: [PATCH v1 3/3] scsi_debug: iouring iopoll support > > Add support of iouring iopoll interface in scsi_debug. > This feature requires shared hosttag support in kernel and driver. > > Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com> > Cc: dgilbert@interlog.com > Cc: linux-block@vger.kernel.org > --- > drivers/scsi/scsi_debug.c | 123 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 123 insertions(+) Hi Doug - Any comment/feedback ? Kashyap
On 2020-11-13 5:50 a.m., Kashyap Desai wrote: >> -----Original Message----- >> From: Kashyap Desai [mailto:kashyap.desai@broadcom.com] >> Sent: Thursday, October 15, 2020 7:07 PM >> To: linux-scsi@vger.kernel.org >> Cc: Kashyap Desai <kashyap.desai@broadcom.com>; dgilbert@interlog.com; >> linux-block@vger.kernel.org >> Subject: [PATCH v1 3/3] scsi_debug: iouring iopoll support >> >> Add support of iouring iopoll interface in scsi_debug. >> This feature requires shared hosttag support in kernel and driver. >> >> Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com> >> Cc: dgilbert@interlog.com >> Cc: linux-block@vger.kernel.org >> --- >> drivers/scsi/scsi_debug.c | 123 ++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 123 insertions(+) > > > Hi Doug - Any comment/feedback ? Hi, I'm testing this patch and have found an issue which I have taken up directly with Kashyap. More to follow. Doug Gilbert
On 2020-10-15 9:37 a.m., Kashyap Desai wrote: > Add support of iouring iopoll interface in scsi_debug. > This feature requires shared hosttag support in kernel and driver. I am continuing to test this patch. There is one fix shown inline below plus a question near the end. Doug Gilbert > Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com> > Cc: dgilbert@interlog.com > Cc: linux-block@vger.kernel.org > --- > drivers/scsi/scsi_debug.c | 123 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 123 insertions(+) > > diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c > index a87e40aec11f..4d9cc6af588c 100644 > --- a/drivers/scsi/scsi_debug.c > +++ b/drivers/scsi/scsi_debug.c > @@ -826,6 +826,7 @@ 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); > @@ -5422,6 +5423,14 @@ 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) { > @@ -5604,6 +5613,7 @@ 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); > @@ -5673,6 +5683,7 @@ MODULE_PARM_DESC(sector_size, "logical block size in bytes (def=512)"); > MODULE_PARM_DESC(statistics, "collect statistics on commands, queues (def=0)"); > MODULE_PARM_DESC(strict, "stricter checks: reserved field in cdb (def=0)"); > MODULE_PARM_DESC(submit_queues, "support for block multi-queue (def=1)"); > +MODULE_PARM_DESC(poll_queues, "support for iouring iopoll queues"); > MODULE_PARM_DESC(tur_ms_to_ready, "TEST UNIT READY millisecs before initial good status (def=0)"); > MODULE_PARM_DESC(unmap_alignment, "lowest aligned thin provisioning lba (def=0)"); > MODULE_PARM_DESC(unmap_granularity, "thin provisioning granularity in blocks (def=1)"); > @@ -7140,6 +7151,104 @@ 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_CANQUEUE))) The above line IMO needs to be: if (unlikely((qc_idx < 0) || (qc_idx >= sdebug_max_queue))) If not, when sdebug_max_queue < SDEBUG_CANQUEUE and there is no request waiting then "scp is NULL, ..." is reported suggesting there is an error. > + 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) > { > @@ -7318,6 +7427,8 @@ 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, > @@ -7365,6 +7476,18 @@ 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 = 0; > + > + /* poll queues */ > + if (poll_queues >= submit_queues) { So the above line rules out poll_queues == submit_queues; is that the intention? If so, a short explanation of why in a comment would be helpful. Helpful at least to me who would like to document this option. > + 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)) >
> > On 2020-10-15 9:37 a.m., Kashyap Desai wrote: > > Add support of iouring iopoll interface in scsi_debug. > > This feature requires shared hosttag support in kernel and driver. > > I am continuing to test this patch. There is one fix shown inline below > plus a > question near the end. Hi Doug, I have created add-on patch which includes all your comment. I am also able to see the issue you reported and below patch fix it. I will hold V2 revision of the series and I will wait for your Review-by and Tested-by Tag. diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 4d9cc6af588c..fb328253086d 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -5675,6 +5675,7 @@ 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)"); @@ -5683,7 +5684,6 @@ MODULE_PARM_DESC(sector_size, "logical block size in bytes (def=512)"); MODULE_PARM_DESC(statistics, "collect statistics on commands, queues (def=0)"); MODULE_PARM_DESC(strict, "stricter checks: reserved field in cdb (def=0)"); MODULE_PARM_DESC(submit_queues, "support for block multi-queue (def=1)"); -MODULE_PARM_DESC(poll_queues, "support for iouring iopoll queues"); MODULE_PARM_DESC(tur_ms_to_ready, "TEST UNIT READY millisecs before initial good status (def=0)"); MODULE_PARM_DESC(unmap_alignment, "lowest aligned thin provisioning lba (def=0)"); MODULE_PARM_DESC(unmap_granularity, "thin provisioning granularity in blocks (def=1)"); @@ -7199,7 +7199,7 @@ static int sdebug_blk_mq_poll(struct Scsi_Host *shost, unsigned int 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_CANQUEUE))) + if (unlikely((qc_idx < 0) || (qc_idx >= sdebug_max_queue))) goto out; sqcp = &sqp->qc_arr[qc_idx]; @@ -7477,10 +7477,17 @@ static int sdebug_driver_probe(struct device *dev) hpnt->host_tagset = 1; /* poll queues are possible for nr_hw_queues > 1 */ - if (hpnt->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 */ + /* + * 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; > > + 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_CANQUEUE))) > > The above line IMO needs to be: > if (unlikely((qc_idx < 0) || (qc_idx >= sdebug_max_queue))) > > If not, when sdebug_max_queue < SDEBUG_CANQUEUE and there is no > request waiting then "scp is NULL, ..." is reported suggesting there is an > error. BTW - Is below piece of code at sdebug_q_cmd_complete() requires similar change ? Use sdebug_max_queue instead of SDEBUG_CANQUEUE if (unlikely((qc_idx < 0) || (qc_idx >= SDEBUG_CANQUEUE))) { pr_err("wild qc_idx=%d\n", qc_idx); return; } Kashyap
On 2020-11-30 4:06 a.m., Kashyap Desai wrote: >> >> On 2020-10-15 9:37 a.m., Kashyap Desai wrote: >>> Add support of iouring iopoll interface in scsi_debug. >>> This feature requires shared hosttag support in kernel and driver. >> >> I am continuing to test this patch. There is one fix shown inline below >> plus a >> question near the end. > > Hi Doug, I have created add-on patch which includes all your comment. I am > also able to see the issue you reported and below patch fix it. > I will hold V2 revision of the series and I will wait for your Review-by and > Tested-by Tag. > > diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c > index 4d9cc6af588c..fb328253086d 100644 > --- a/drivers/scsi/scsi_debug.c > +++ b/drivers/scsi/scsi_debug.c > @@ -5675,6 +5675,7 @@ 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)"); > @@ -5683,7 +5684,6 @@ MODULE_PARM_DESC(sector_size, "logical block size in > bytes (def=512)"); > MODULE_PARM_DESC(statistics, "collect statistics on commands, queues > (def=0)"); > MODULE_PARM_DESC(strict, "stricter checks: reserved field in cdb (def=0)"); > MODULE_PARM_DESC(submit_queues, "support for block multi-queue (def=1)"); > -MODULE_PARM_DESC(poll_queues, "support for iouring iopoll queues"); > MODULE_PARM_DESC(tur_ms_to_ready, "TEST UNIT READY millisecs before initial > good status (def=0)"); > MODULE_PARM_DESC(unmap_alignment, "lowest aligned thin provisioning lba > (def=0)"); > MODULE_PARM_DESC(unmap_granularity, "thin provisioning granularity in > blocks (def=1)"); > @@ -7199,7 +7199,7 @@ static int sdebug_blk_mq_poll(struct Scsi_Host *shost, > unsigned int 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_CANQUEUE))) > + if (unlikely((qc_idx < 0) || (qc_idx >= sdebug_max_queue))) > goto out; > > sqcp = &sqp->qc_arr[qc_idx]; > @@ -7477,10 +7477,17 @@ static int sdebug_driver_probe(struct device *dev) > hpnt->host_tagset = 1; > > /* poll queues are possible for nr_hw_queues > 1 */ > - if (hpnt->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 */ > + /* > + * 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; > > Kashyap, I struggled with this patch, first the line wrap, then the last two patch segments not applying. Could you send me the scsi_debug.c file attached to an email? >>> + 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_CANQUEUE))) >> >> The above line IMO needs to be: >> if (unlikely((qc_idx < 0) || (qc_idx >= sdebug_max_queue))) >> >> If not, when sdebug_max_queue < SDEBUG_CANQUEUE and there is no >> request waiting then "scp is NULL, ..." is reported suggesting there is an >> error. > > BTW - Is below piece of code at sdebug_q_cmd_complete() requires similar > change ? > Use sdebug_max_queue instead of SDEBUG_CANQUEUE > if (unlikely((qc_idx < 0) || (qc_idx >= SDEBUG_CANQUEUE))) { > pr_err("wild qc_idx=%d\n", qc_idx); > return; > } Yes, I need to look at this. sdebug_max_queue is initialized to SDEBUG_CANQUEUE but then can be overridden by the invocation line parameters. Several arrays in structures are sized by SDEBUG_CANQUEUE which will remain. But most SDEBUG_CANQUEUE uses inside driver functions can probably be replaced by sdebug_max_queue when I confirm that it is safe. Since sdebug_max_queue <= SDEBUG_CANQUEUE and the fields in between should always be zero, the current situation just leads to wasted cycles. Doug Gilbert
On 2020-11-30 4:06 a.m., Kashyap Desai wrote: >> >> On 2020-10-15 9:37 a.m., Kashyap Desai wrote: >>> Add support of iouring iopoll interface in scsi_debug. >>> This feature requires shared hosttag support in kernel and driver. >> >> I am continuing to test this patch. There is one fix shown inline below >> plus a >> question near the end. > > Hi Doug, I have created add-on patch which includes all your comment. I am > also able to see the issue you reported and below patch fix it. > I will hold V2 revision of the series and I will wait for your Review-by and > Tested-by Tag. Thanks, that is a good explanation of why poll_queues must be less than submit_queues. Acked-by: Douglas Gilbert <dgilbert@interlog.com> Tested-by: Douglas Gilbert <dgilbert@interlog.com>
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index a87e40aec11f..4d9cc6af588c 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -826,6 +826,7 @@ 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); @@ -5422,6 +5423,14 @@ 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) { @@ -5604,6 +5613,7 @@ 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); @@ -5673,6 +5683,7 @@ MODULE_PARM_DESC(sector_size, "logical block size in bytes (def=512)"); MODULE_PARM_DESC(statistics, "collect statistics on commands, queues (def=0)"); MODULE_PARM_DESC(strict, "stricter checks: reserved field in cdb (def=0)"); MODULE_PARM_DESC(submit_queues, "support for block multi-queue (def=1)"); +MODULE_PARM_DESC(poll_queues, "support for iouring iopoll queues"); MODULE_PARM_DESC(tur_ms_to_ready, "TEST UNIT READY millisecs before initial good status (def=0)"); MODULE_PARM_DESC(unmap_alignment, "lowest aligned thin provisioning lba (def=0)"); MODULE_PARM_DESC(unmap_granularity, "thin provisioning granularity in blocks (def=1)"); @@ -7140,6 +7151,104 @@ 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_CANQUEUE))) + 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) { @@ -7318,6 +7427,8 @@ 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, @@ -7365,6 +7476,18 @@ 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 = 0; + + /* poll queues */ + 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))
Add support of iouring iopoll interface in scsi_debug. This feature requires shared hosttag support in kernel and driver. Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com> Cc: dgilbert@interlog.com Cc: linux-block@vger.kernel.org --- drivers/scsi/scsi_debug.c | 123 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+)