From: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Date: Sat, 9 Jul 2022 01:20:20 +0530
Subject: scsi: mpi3mr: Reduce VD queue depth on detecting throttling
Git-commit: cf1ce8b715240e3e4a86162788958444e9208472
Patch-mainline: v6.0-rc1
References: jsc#PED-1446
Reduce the VD queue depth on detecting the throttling condition.
[mkp: incorporate fix for pointer cast issue reported by the test
robot and Guenter Roeck]
Link: https://lore.kernel.org/r/20220708195020.8323-3-sreekanth.reddy@broadcom.com
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Lee Duncan <lduncan@suse.com>
---
drivers/scsi/mpi3mr/mpi3mr.h | 10 ++++
drivers/scsi/mpi3mr/mpi3mr_fw.c | 4 ++
drivers/scsi/mpi3mr/mpi3mr_os.c | 122 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 136 insertions(+)
diff --git a/drivers/scsi/mpi3mr/mpi3mr.h b/drivers/scsi/mpi3mr/mpi3mr.h
index 6bb3311b8620..0935b2e80662 100644
--- a/drivers/scsi/mpi3mr/mpi3mr.h
+++ b/drivers/scsi/mpi3mr/mpi3mr.h
@@ -436,6 +436,10 @@ struct mpi3mr_intr_info {
* struct mpi3mr_throttle_group_info - Throttle group info
*
* @io_divert: Flag indicates io divert is on or off for the TG
+ * @need_qd_reduction: Flag to indicate QD reduction is needed
+ * @qd_reduction: Queue Depth reduction in units of 10%
+ * @fw_qd: QueueDepth value reported by the firmware
+ * @modified_qd: Modified QueueDepth value due to throttling
* @id: Throttle Group ID.
* @high: High limit to turn on throttling in 512 byte blocks
* @low: Low limit to turn off throttling in 512 byte blocks
@@ -443,6 +447,10 @@ struct mpi3mr_intr_info {
*/
struct mpi3mr_throttle_group_info {
u8 io_divert;
+ u8 need_qd_reduction;
+ u8 qd_reduction;
+ u16 fw_qd;
+ u16 modified_qd;
u16 id;
u32 high;
u32 low;
@@ -486,6 +494,7 @@ struct tgt_dev_pcie {
* cached from firmware given data
*
* @state: State of the VD
+ * @tg_qd_reduction: Queue Depth reduction in units of 10%
* @tg_id: VDs throttle group ID
* @high: High limit to turn on throttling in 512 byte blocks
* @low: Low limit to turn off throttling in 512 byte blocks
@@ -493,6 +502,7 @@ struct tgt_dev_pcie {
*/
struct tgt_dev_vd {
u8 state;
+ u8 tg_qd_reduction;
u16 tg_id;
u32 tg_high;
u32 tg_low;
diff --git a/drivers/scsi/mpi3mr/mpi3mr_fw.c b/drivers/scsi/mpi3mr/mpi3mr_fw.c
index ab79374bb6e1..6e39f7969e63 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_fw.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_fw.c
@@ -4077,9 +4077,13 @@ void mpi3mr_memset_buffers(struct mpi3mr_ioc *mrioc)
tg = mrioc->throttle_groups;
for (i = 0; i < mrioc->num_io_throttle_group; i++, tg++) {
tg->id = 0;
+ tg->fw_qd = 0;
+ tg->modified_qd = 0;
tg->io_divert = 0;
+ tg->need_qd_reduction = 0;
tg->high = 0;
tg->low = 0;
+ tg->qd_reduction = 0;
atomic_set(&tg->pend_large_data_sz, 0);
}
}
diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
index e1ccb5fcd68a..4102636df4fc 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_os.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
@@ -38,6 +38,8 @@ MODULE_PARM_DESC(logging_level,
static void mpi3mr_send_event_ack(struct mpi3mr_ioc *mrioc, u8 event,
struct mpi3mr_drv_cmd *cmdparam, u32 event_ctx);
+#define MPI3MR_DRIVER_EVENT_TG_QD_REDUCTION (0xFFFF)
+
/**
* mpi3mr_host_tag_for_scmd - Get host tag for a scmd
* @mrioc: Adapter instance reference
@@ -354,6 +356,50 @@ void mpi3mr_cleanup_fwevt_list(struct mpi3mr_ioc *mrioc)
}
}
+/**
+ * mpi3mr_queue_qd_reduction_event - Queue TG QD reduction event
+ * @mrioc: Adapter instance reference
+ * @tg: Throttle group information pointer
+ *
+ * Accessor to queue on synthetically generated driver event to
+ * the event worker thread, the driver event will be used to
+ * reduce the QD of all VDs in the TG from the worker thread.
+ *
+ * Return: None.
+ */
+static void mpi3mr_queue_qd_reduction_event(struct mpi3mr_ioc *mrioc,
+ struct mpi3mr_throttle_group_info *tg)
+{
+ struct mpi3mr_fwevt *fwevt;
+ u16 sz = sizeof(struct mpi3mr_throttle_group_info *);
+
+ /*
+ * If the QD reduction event is already queued due to throttle and if
+ * the QD is not restored through device info change event
+ * then dont queue further reduction events
+ */
+ if (tg->fw_qd != tg->modified_qd)
+ return;
+
+ fwevt = mpi3mr_alloc_fwevt(sz);
+ if (!fwevt) {
+ ioc_warn(mrioc, "failed to queue TG QD reduction event\n");
+ return;
+ }
+ *(struct mpi3mr_throttle_group_info **)fwevt->event_data = tg;
+ fwevt->mrioc = mrioc;
+ fwevt->event_id = MPI3MR_DRIVER_EVENT_TG_QD_REDUCTION;
+ fwevt->send_ack = 0;
+ fwevt->process_evt = 1;
+ fwevt->evt_ctx = 0;
+ fwevt->event_data_size = sz;
+ tg->modified_qd = max_t(u16, (tg->fw_qd * tg->qd_reduction) / 10, 8);
+
+ dprint_event_bh(mrioc, "qd reduction event queued for tg_id(%d)\n",
+ tg->id);
+ mpi3mr_fwevt_add_to_list(mrioc, fwevt);
+}
+
/**
* mpi3mr_invalidate_devhandles -Invalidate device handles
* @mrioc: Adapter instance reference
@@ -880,6 +926,7 @@ static int mpi3mr_change_queue_depth(struct scsi_device *sdev,
else if (!q_depth)
q_depth = MPI3MR_DEFAULT_SDEV_QD;
retval = scsi_change_queue_depth(sdev, q_depth);
+ sdev->max_queue_depth = sdev->queue_depth;
return retval;
}
@@ -1100,6 +1147,11 @@ static void mpi3mr_update_tgtdev(struct mpi3mr_ioc *mrioc,
tg->id = vdinf_io_throttle_group;
tg->high = tgtdev->dev_spec.vd_inf.tg_high;
tg->low = tgtdev->dev_spec.vd_inf.tg_low;
+ tg->qd_reduction =
+ tgtdev->dev_spec.vd_inf.tg_qd_reduction;
+ if (is_added == true)
+ tg->fw_qd = tgtdev->q_depth;
+ tg->modified_qd = tgtdev->q_depth;
}
tgtdev->dev_spec.vd_inf.tg = tg;
if (scsi_tgt_priv_data)
@@ -1493,6 +1545,60 @@ static void mpi3mr_logdata_evt_bh(struct mpi3mr_ioc *mrioc,
fwevt->event_data_size);
}
+/**
+ * mpi3mr_update_sdev_qd - Update SCSI device queue depath
+ * @sdev: SCSI device reference
+ * @data: Queue depth reference
+ *
+ * This is an iterator function called for each SCSI device in a
+ * target to update the QD of each SCSI device.
+ *
+ * Return: Nothing.
+ */
+static void mpi3mr_update_sdev_qd(struct scsi_device *sdev, void *data)
+{
+ u16 *q_depth = (u16 *)data;
+
+ scsi_change_queue_depth(sdev, (int)*q_depth);
+ sdev->max_queue_depth = sdev->queue_depth;
+}
+
+/**
+ * mpi3mr_set_qd_for_all_vd_in_tg -set QD for TG VDs
+ * @mrioc: Adapter instance reference
+ * @tg: Throttle group information pointer
+ *
+ * Accessor to reduce QD for each device associated with the
+ * given throttle group.
+ *
+ * Return: None.
+ */
+static void mpi3mr_set_qd_for_all_vd_in_tg(struct mpi3mr_ioc *mrioc,
+ struct mpi3mr_throttle_group_info *tg)
+{
+ unsigned long flags;
+ struct mpi3mr_tgt_dev *tgtdev;
+ struct mpi3mr_stgt_priv_data *tgt_priv;
+
+
+ spin_lock_irqsave(&mrioc->tgtdev_lock, flags);
+ list_for_each_entry(tgtdev, &mrioc->tgtdev_list, list) {
+ if (tgtdev->starget && tgtdev->starget->hostdata) {
+ tgt_priv = tgtdev->starget->hostdata;
+ if (tgt_priv->throttle_group == tg) {
+ dprint_event_bh(mrioc,
+ "updating qd due to throttling for persist_id(%d) original_qd(%d), reduced_qd (%d)\n",
+ tgt_priv->perst_id, tgtdev->q_depth,
+ tg->modified_qd);
+ starget_for_each_device(tgtdev->starget,
+ (void *)&tg->modified_qd,
+ mpi3mr_update_sdev_qd);
+ }
+ }
+ }
+ spin_unlock_irqrestore(&mrioc->tgtdev_lock, flags);
+}
+
/**
* mpi3mr_fwevt_bh - Firmware event bottomhalf handler
* @mrioc: Adapter instance reference
@@ -1550,6 +1656,20 @@ static void mpi3mr_fwevt_bh(struct mpi3mr_ioc *mrioc,
mpi3mr_logdata_evt_bh(mrioc, fwevt);
break;
}
+ case MPI3MR_DRIVER_EVENT_TG_QD_REDUCTION:
+ {
+ struct mpi3mr_throttle_group_info *tg;
+
+ tg = *(struct mpi3mr_throttle_group_info **)fwevt->event_data;
+ dprint_event_bh(mrioc,
+ "qd reduction event processed for tg_id(%d) reduction_needed(%d)\n",
+ tg->id, tg->need_qd_reduction);
+ if (tg->need_qd_reduction) {
+ mpi3mr_set_qd_for_all_vd_in_tg(mrioc, tg);
+ tg->need_qd_reduction = 0;
+ }
+ break;
+ }
default:
break;
}
@@ -4234,8 +4354,10 @@ static int mpi3mr_qcmd(struct Scsi_Host *shost,
mrioc->io_throttle_high) ||
(tg_pend_data_len >= tg->high))) {
tg->io_divert = 1;
+ tg->need_qd_reduction = 1;
mpi3mr_set_io_divert_for_all_vd_in_tg(mrioc,
tg, 1);
+ mpi3mr_queue_qd_reduction_event(mrioc, tg);
}
} else {
ioc_pend_data_len = atomic_add_return(data_len_blks,