diff mbox series

[2/3] megaraid_sas: iouring iopoll support

Message ID 20201014122655.201272-1-kashyap.desai@broadcom.com (mailing list archive)
State Changes Requested
Headers show
Series [1/3] add io_uring with IOPOLL support in scsi layer | expand

Commit Message

Kashyap Desai Oct. 14, 2020, 12:26 p.m. UTC
Add support of iouring iopoll interface. This feature requires shared
hosttag support in kernel and driver.

Driver will work in non-IRQ mode = There will not be any msix vector
associated for poll_queues and h/w can still work in this mode.
MegaRaid h/w is single submission queue and multiple reply queue, but
using shared host tagset support it will enable simulated multiple hw queue.

Driver allocates some extra reply queues and it will be marked as poll_queue.
These poll_queues will not have associated msix vectors. All the IO
completion on this queue will be done from IOPOLL interface.

megaraid_sas driver having 8 poll_queues and using io_uring hiprio=1 settings,
It can reach 3.2M IOPs and there is zero interrupt generated by h/w.

This feature can be enabled using module parameter poll_queues.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: sumit.saxena@broadcom.com
Cc: chandrakanth.patil@broadcom.com
Cc: linux-block@vger.kernel.org
---
 drivers/scsi/megaraid/megaraid_sas.h        |  2 +
 drivers/scsi/megaraid/megaraid_sas_base.c   | 90 ++++++++++++++++++---
 drivers/scsi/megaraid/megaraid_sas_fusion.c | 43 +++++++++-
 drivers/scsi/megaraid/megaraid_sas_fusion.h |  3 +
 4 files changed, 127 insertions(+), 11 deletions(-)

Comments

kernel test robot Oct. 14, 2020, 4:05 p.m. UTC | #1
Hi Kashyap,

I love your patch! Perhaps something to improve:

[auto build test WARNING on next-20201013]
[cannot apply to scsi/for-next mkp-scsi/for-next v5.9 v5.9-rc8 v5.9-rc7 v5.9]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Kashyap-Desai/add-io_uring-with-IOPOLL-support-in-scsi-layer/20201014-202916
base:    f2fb1afc57304f9dd68c20a08270e287470af2eb
config: xtensa-allyesconfig (attached as .config)
compiler: xtensa-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/4f93510c3e695f6f22822115f6587db68fb40e5c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Kashyap-Desai/add-io_uring-with-IOPOLL-support-in-scsi-layer/20201014-202916
        git checkout 4f93510c3e695f6f22822115f6587db68fb40e5c
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=xtensa 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/scsi/megaraid/megaraid_sas_fusion.c:3652:5: warning: no previous prototype for 'megasas_blk_mq_poll' [-Wmissing-prototypes]
    3652 | int megasas_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
         |     ^~~~~~~~~~~~~~~~~~~

vim +/megasas_blk_mq_poll +3652 drivers/scsi/megaraid/megaraid_sas_fusion.c

  3651	
> 3652	int megasas_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
  3653	{
  3654	
  3655		struct megasas_instance *instance;
  3656		int num_entries = 0;
  3657		struct fusion_context *fusion;
  3658	
  3659		instance = (struct megasas_instance *)shost->hostdata;
  3660	
  3661		fusion = instance->ctrl_context;
  3662	
  3663		queue_num = queue_num + instance->low_latency_index_start;
  3664	
  3665		if (!atomic_add_unless(&fusion->busy_mq_poll[queue_num], 1, 1))
  3666			return 0;
  3667	
  3668		num_entries = complete_cmd_fusion(instance, queue_num, NULL);
  3669		atomic_dec(&fusion->busy_mq_poll[queue_num]);
  3670	
  3671		return num_entries;
  3672	}
  3673	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
kernel test robot Oct. 14, 2020, 6:23 p.m. UTC | #2
Hi Kashyap,

I love your patch! Perhaps something to improve:

[auto build test WARNING on next-20201013]
[cannot apply to scsi/for-next mkp-scsi/for-next v5.9 v5.9-rc8 v5.9-rc7 v5.9]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Kashyap-Desai/add-io_uring-with-IOPOLL-support-in-scsi-layer/20201014-202916
base:    f2fb1afc57304f9dd68c20a08270e287470af2eb
config: x86_64-randconfig-a004-20201014 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project e7fe3c6dfede8d5781bd000741c3dea7088307a4)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/4f93510c3e695f6f22822115f6587db68fb40e5c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Kashyap-Desai/add-io_uring-with-IOPOLL-support-in-scsi-layer/20201014-202916
        git checkout 4f93510c3e695f6f22822115f6587db68fb40e5c
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/scsi/megaraid/megaraid_sas_fusion.c:3652:5: warning: no previous prototype for function 'megasas_blk_mq_poll' [-Wmissing-prototypes]
   int megasas_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
       ^
   drivers/scsi/megaraid/megaraid_sas_fusion.c:3652:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int megasas_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
   ^
   static 
   1 warning generated.

vim +/megasas_blk_mq_poll +3652 drivers/scsi/megaraid/megaraid_sas_fusion.c

  3651	
> 3652	int megasas_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
  3653	{
  3654	
  3655		struct megasas_instance *instance;
  3656		int num_entries = 0;
  3657		struct fusion_context *fusion;
  3658	
  3659		instance = (struct megasas_instance *)shost->hostdata;
  3660	
  3661		fusion = instance->ctrl_context;
  3662	
  3663		queue_num = queue_num + instance->low_latency_index_start;
  3664	
  3665		if (!atomic_add_unless(&fusion->busy_mq_poll[queue_num], 1, 1))
  3666			return 0;
  3667	
  3668		num_entries = complete_cmd_fusion(instance, queue_num, NULL);
  3669		atomic_dec(&fusion->busy_mq_poll[queue_num]);
  3670	
  3671		return num_entries;
  3672	}
  3673	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index 5e4137f10e0e..4bf6fde49565 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -2212,6 +2212,7 @@  struct megasas_irq_context {
 	struct irq_poll irqpoll;
 	bool irq_poll_scheduled;
 	bool irq_line_enable;
+	atomic_t   in_used;
 };
 
 struct MR_DRV_SYSTEM_INFO {
@@ -2446,6 +2447,7 @@  struct megasas_instance {
 	bool support_pci_lane_margining;
 	u8  low_latency_index_start;
 	int perf_mode;
+	int iopoll_q_count;
 };
 
 struct MR_LD_VF_MAP {
diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 020270ce790b..e2c307523a8a 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -114,6 +114,15 @@  unsigned int enable_sdev_max_qd;
 module_param(enable_sdev_max_qd, int, 0444);
 MODULE_PARM_DESC(enable_sdev_max_qd, "Enable sdev max qd as can_queue. Default: 0");
 
+int poll_queues;
+module_param(poll_queues, int, 0444);
+MODULE_PARM_DESC(poll_queues, "Number of queues to be use for io_uring poll mode.\n\t\t"
+		"This parameter is effective only if host_tagset_enable=1 &\n\t\t"
+		"It is not applicable for MFI_SERIES. &\n\t\t"
+		"Driver will work in latency mode. &\n\t\t"
+		"High iops queues are not allocated &\n\t\t"
+		);
+
 int host_tagset_enable = 1;
 module_param(host_tagset_enable, int, 0444);
 MODULE_PARM_DESC(host_tagset_enable, "Shared host tagset enable/disable Default: enable(1)");
@@ -207,6 +216,7 @@  static bool support_pci_lane_margining;
 static spinlock_t poll_aen_lock;
 
 extern struct dentry *megasas_debugfs_root;
+extern int megasas_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num);
 
 void
 megasas_complete_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd,
@@ -3127,14 +3137,45 @@  megasas_bios_param(struct scsi_device *sdev, struct block_device *bdev,
 static int megasas_map_queues(struct Scsi_Host *shost)
 {
 	struct megasas_instance *instance;
+	int i, qoff, offset;
 
 	instance = (struct megasas_instance *)shost->hostdata;
 
 	if (shost->nr_hw_queues == 1)
 		return 0;
 
-	return blk_mq_pci_map_queues(&shost->tag_set.map[HCTX_TYPE_DEFAULT],
-			instance->pdev, instance->low_latency_index_start);
+	offset = instance->low_latency_index_start;
+
+	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 = instance->msix_vectors - offset;
+		else if (i == HCTX_TYPE_POLL)
+			map->nr_queues = instance->iopoll_q_count;
+
+		if (!map->nr_queues) {
+			BUG_ON(i == HCTX_TYPE_DEFAULT);
+			continue;
+		}
+
+		/*
+		 * The poll queue(s) doesn't have an IRQ (and hence IRQ
+		 * affinity), so use the regular blk-mq cpu mapping
+		 */
+		map->queue_offset = qoff;
+		if (i != HCTX_TYPE_POLL)
+			blk_mq_pci_map_queues(map, instance->pdev, offset);
+		else
+			blk_mq_map_queues(map);
+
+		qoff += map->nr_queues;
+		offset += map->nr_queues;
+	}
+
+	return 0;
 }
 
 static void megasas_aen_polling(struct work_struct *work);
@@ -3446,6 +3487,7 @@  static struct scsi_host_template megasas_template = {
 	.shost_attrs = megaraid_host_attrs,
 	.bios_param = megasas_bios_param,
 	.map_queues = megasas_map_queues,
+	.mq_poll = megasas_blk_mq_poll,
 	.change_queue_depth = scsi_change_queue_depth,
 	.max_segment_size = 0xffffffff,
 };
@@ -5834,13 +5876,16 @@  __megasas_alloc_irq_vectors(struct megasas_instance *instance)
 	irq_flags = PCI_IRQ_MSIX;
 
 	if (instance->smp_affinity_enable)
-		irq_flags |= PCI_IRQ_AFFINITY;
+		irq_flags |= PCI_IRQ_AFFINITY | PCI_IRQ_ALL_TYPES;
 	else
 		descp = NULL;
 
+	/* Do not allocate msix vectors for poll_queues.
+	 * msix_vectors is always within a range of FW supported reply queue.
+	 */
 	i = pci_alloc_irq_vectors_affinity(instance->pdev,
 		instance->low_latency_index_start,
-		instance->msix_vectors, irq_flags, descp);
+		instance->msix_vectors - instance->iopoll_q_count, irq_flags, descp);
 
 	return i;
 }
@@ -5856,10 +5901,25 @@  megasas_alloc_irq_vectors(struct megasas_instance *instance)
 	int i;
 	unsigned int num_msix_req;
 
+	instance->iopoll_q_count = 0;
+	if ((instance->adapter_type != MFI_SERIES) &&
+		poll_queues) {
+
+		instance->perf_mode = MR_LATENCY_PERF_MODE;
+		instance->low_latency_index_start = 1;
+
+		/* reserve for default and non-mananged pre-vector. */
+		if (instance->msix_vectors > (instance->iopoll_q_count + 2))
+			instance->iopoll_q_count = poll_queues;
+		else
+			instance->iopoll_q_count = 0;
+	}
+
 	i = __megasas_alloc_irq_vectors(instance);
 
-	if ((instance->perf_mode == MR_BALANCED_PERF_MODE) &&
-	    (i != instance->msix_vectors)) {
+	if (((instance->perf_mode == MR_BALANCED_PERF_MODE)
+		|| instance->iopoll_q_count) &&
+	    (i != (instance->msix_vectors - instance->iopoll_q_count))) {
 		if (instance->msix_vectors)
 			pci_free_irq_vectors(instance->pdev);
 		/* Disable Balanced IOPS mode and try realloc vectors */
@@ -5870,12 +5930,15 @@  megasas_alloc_irq_vectors(struct megasas_instance *instance)
 		instance->msix_vectors = min(num_msix_req,
 				instance->msix_vectors);
 
+		instance->iopoll_q_count = 0;
 		i = __megasas_alloc_irq_vectors(instance);
 
 	}
 
 	dev_info(&instance->pdev->dev,
-		"requested/available msix %d/%d\n", instance->msix_vectors, i);
+		"requested/available msix %d/%d poll_queue %d\n",
+			instance->msix_vectors - instance->iopoll_q_count,
+			i, instance->iopoll_q_count);
 
 	if (i > 0)
 		instance->msix_vectors = i;
@@ -6841,12 +6904,18 @@  static int megasas_io_attach(struct megasas_instance *instance)
 		instance->smp_affinity_enable) {
 		host->host_tagset = 1;
 		host->nr_hw_queues = instance->msix_vectors -
-			instance->low_latency_index_start;
+			instance->low_latency_index_start + instance->iopoll_q_count;
+		if (instance->iopoll_q_count)
+			host->nr_maps = 3;
+	} else {
+		instance->iopoll_q_count = 0;
 	}
 
 	dev_info(&instance->pdev->dev,
-		"Max firmware commands: %d shared with nr_hw_queues = %d\n",
-		instance->max_fw_cmds, host->nr_hw_queues);
+		"Max firmware commands: %d shared with default "
+		"hw_queues = %d poll_queues %d\n", instance->max_fw_cmds,
+		host->nr_hw_queues - instance->iopoll_q_count,
+		instance->iopoll_q_count);
 	/*
 	 * Notify the mid-layer about the new controller
 	 */
@@ -8907,6 +8976,7 @@  static int __init megasas_init(void)
 		msix_vectors = 1;
 		rdpq_enable = 0;
 		dual_qdepth_disable = 1;
+		poll_queues = 0;
 	}
 
 	/*
diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index fd607287608e..49c8cc3507e0 100644
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -685,6 +685,8 @@  megasas_alloc_reply_fusion(struct megasas_instance *instance)
 	fusion = instance->ctrl_context;
 
 	count = instance->msix_vectors > 0 ? instance->msix_vectors : 1;
+	count += instance->iopoll_q_count;
+
 	fusion->reply_frames_desc_pool =
 			dma_pool_create("mr_reply", &instance->pdev->dev,
 				fusion->reply_alloc_sz * count, 16, 0);
@@ -779,6 +781,7 @@  megasas_alloc_rdpq_fusion(struct megasas_instance *instance)
 	}
 
 	msix_count = instance->msix_vectors > 0 ? instance->msix_vectors : 1;
+	msix_count += instance->iopoll_q_count;
 
 	fusion->reply_frames_desc_pool = dma_pool_create("mr_rdpq",
 							 &instance->pdev->dev,
@@ -1129,7 +1132,7 @@  megasas_ioc_init_fusion(struct megasas_instance *instance)
 			MPI2_IOCINIT_MSGFLAG_RDPQ_ARRAY_MODE : 0;
 	IOCInitMessage->SystemRequestFrameBaseAddress = cpu_to_le64(fusion->io_request_frames_phys);
 	IOCInitMessage->SenseBufferAddressHigh = cpu_to_le32(upper_32_bits(fusion->sense_phys_addr));
-	IOCInitMessage->HostMSIxVectors = instance->msix_vectors;
+	IOCInitMessage->HostMSIxVectors = instance->msix_vectors + instance->iopoll_q_count;
 	IOCInitMessage->HostPageSize = MR_DEFAULT_NVME_PAGE_SHIFT;
 
 	time = ktime_get_real();
@@ -1823,6 +1826,8 @@  megasas_init_adapter_fusion(struct megasas_instance *instance)
 		 sizeof(union MPI2_SGE_IO_UNION))/16;
 
 	count = instance->msix_vectors > 0 ? instance->msix_vectors : 1;
+	count += instance->iopoll_q_count;
+
 	for (i = 0 ; i < count; i++)
 		fusion->last_reply_idx[i] = 0;
 
@@ -1835,6 +1840,9 @@  megasas_init_adapter_fusion(struct megasas_instance *instance)
 				MEGASAS_FUSION_IOCTL_CMDS);
 	sema_init(&instance->ioctl_sem, MEGASAS_FUSION_IOCTL_CMDS);
 
+	for (i = 0; i < MAX_MSIX_QUEUES_FUSION; i++)
+		atomic_set(&fusion->busy_mq_poll[i], 0);
+
 	if (megasas_alloc_ioc_init_frame(instance))
 		return 1;
 
@@ -3500,6 +3508,9 @@  complete_cmd_fusion(struct megasas_instance *instance, u32 MSIxIndex,
 	if (reply_descript_type == MPI2_RPY_DESCRIPT_FLAGS_UNUSED)
 		return IRQ_NONE;
 
+	if (irq_context && !atomic_add_unless(&irq_context->in_used, 1, 1))
+		return 0;
+
 	num_completed = 0;
 
 	while (d_val.u.low != cpu_to_le32(UINT_MAX) &&
@@ -3613,6 +3624,7 @@  complete_cmd_fusion(struct megasas_instance *instance, u32 MSIxIndex,
 					irq_context->irq_line_enable = true;
 					irq_poll_sched(&irq_context->irqpoll);
 				}
+				atomic_dec(&irq_context->in_used);
 				return num_completed;
 			}
 		}
@@ -3630,9 +3642,36 @@  complete_cmd_fusion(struct megasas_instance *instance, u32 MSIxIndex,
 				instance->reply_post_host_index_addr[0]);
 		megasas_check_and_restore_queue_depth(instance);
 	}
+
+	if (irq_context)
+		atomic_dec(&irq_context->in_used);
+
 	return num_completed;
 }
 
+int megasas_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
+{
+
+	struct megasas_instance *instance;
+	int num_entries = 0;
+	struct fusion_context *fusion;
+
+	instance = (struct megasas_instance *)shost->hostdata;
+
+	fusion = instance->ctrl_context;
+
+	queue_num = queue_num + instance->low_latency_index_start;
+
+	if (!atomic_add_unless(&fusion->busy_mq_poll[queue_num], 1, 1))
+		return 0;
+
+	num_entries = complete_cmd_fusion(instance, queue_num, NULL);
+	atomic_dec(&fusion->busy_mq_poll[queue_num]);
+
+	return num_entries;
+}
+
+
 /**
  * megasas_enable_irq_poll() - enable irqpoll
  * @instance:			Adapter soft state
@@ -4164,6 +4203,8 @@  void  megasas_reset_reply_desc(struct megasas_instance *instance)
 
 	fusion = instance->ctrl_context;
 	count = instance->msix_vectors > 0 ? instance->msix_vectors : 1;
+	count += instance->iopoll_q_count;
+
 	for (i = 0 ; i < count ; i++) {
 		fusion->last_reply_idx[i] = 0;
 		reply_desc = fusion->reply_frames_desc[i];
diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.h b/drivers/scsi/megaraid/megaraid_sas_fusion.h
index 30de4b01f703..242ff58a3404 100644
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.h
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.h
@@ -1303,6 +1303,9 @@  struct fusion_context {
 	u8 *sense;
 	dma_addr_t sense_phys_addr;
 
+	atomic_t   busy_mq_poll[MAX_MSIX_QUEUES_FUSION];
+
+
 	dma_addr_t reply_frames_desc_phys[MAX_MSIX_QUEUES_FUSION];
 	union MPI2_REPLY_DESCRIPTORS_UNION *reply_frames_desc[MAX_MSIX_QUEUES_FUSION];
 	struct rdpq_alloc_detail rdpq_tracker[RDPQ_MAX_CHUNK_COUNT];