scsi: megaraid_sas: Replace sdev_busy with local counter

Use local tracking of per-sdev outstanding command since sdev_busy in SCSI
mid layer is improved for performance reason using sbitmap (earlier it was
atomic variable).

Link: https://lore.kernel.org/r/20210122023317.687987-11-ming.lei@redhat.com
Cc: Omar Sandoval <osandov@fb.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Sumanesh Samanta <sumanesh.samanta@broadcom.com>
Cc: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index 0f808d6..0c6a56b 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -2019,10 +2019,12 @@ union megasas_frame {
  * struct MR_PRIV_DEVICE - sdev private hostdata
  * @is_tm_capable: firmware managed tm_capable flag
  * @tm_busy: TM request is in progress
+ * @sdev_priv_busy: pending command per sdev
  */
 struct MR_PRIV_DEVICE {
        bool is_tm_capable;
        bool tm_busy;
+       atomic_t sdev_priv_busy;
        atomic_t r1_ldio_hint;
        u8 interface_type;
        u8 task_abort_tmo;

diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index 38fc946..f344856 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -220,6 +220,40 @@ megasas_clear_intr_fusion(struct megasas_instance *instance)
        return 1;
 }
 
+static inline void
+megasas_sdev_busy_inc(struct megasas_instance *instance,
+                     struct scsi_cmnd *scmd)
+{
+       if (instance->perf_mode == MR_BALANCED_PERF_MODE) {
+               struct MR_PRIV_DEVICE *mr_device_priv_data =
+                       scmd->device->hostdata;
+               atomic_inc(&mr_device_priv_data->sdev_priv_busy);
+       }
+}
+
+static inline void
+megasas_sdev_busy_dec(struct megasas_instance *instance,
+                     struct scsi_cmnd *scmd)
+{
+       if (instance->perf_mode == MR_BALANCED_PERF_MODE) {
+               struct MR_PRIV_DEVICE *mr_device_priv_data =
+                       scmd->device->hostdata;
+               atomic_dec(&mr_device_priv_data->sdev_priv_busy);
+       }
+}
+
+static inline int
+megasas_sdev_busy_read(struct megasas_instance *instance,
+                      struct scsi_cmnd *scmd)
+{
+       if (instance->perf_mode == MR_BALANCED_PERF_MODE) {
+               struct MR_PRIV_DEVICE *mr_device_priv_data =
+                       scmd->device->hostdata;
+               return atomic_read(&mr_device_priv_data->sdev_priv_busy);
+       }
+       return 0;
+}
+
 /**
  * megasas_get_cmd_fusion -    Get a command from the free pool
  * @instance:          Adapter soft state
@@ -357,15 +391,9 @@ megasas_get_msix_index(struct megasas_instance *instance,
                       struct megasas_cmd_fusion *cmd,
                       u8 data_arms)
 {
-       int sdev_busy;
-
-       /* TBD - if sml remove device_busy in future, driver
-        * should track counter in internal structure.
-        */
-       sdev_busy = atomic_read(&scmd->device->device_busy);
-
        if (instance->perf_mode == MR_BALANCED_PERF_MODE &&
-           sdev_busy > (data_arms * MR_DEVICE_HIGH_IOPS_DEPTH)) {
+           (megasas_sdev_busy_read(instance, scmd) >
+            (data_arms * MR_DEVICE_HIGH_IOPS_DEPTH))) {
                cmd->request_desc->SCSIIO.MSIxIndex =
                        mega_mod64((atomic64_add_return(1, &instance->high_iops_outstanding) /
                                        MR_HIGH_IOPS_BATCH_COUNT), instance->low_latency_index_start);
@@ -3390,6 +3418,7 @@ megasas_build_and_issue_cmd_fusion(struct megasas_instance *instance,
         * Issue the command to the FW
         */
 
+       megasas_sdev_busy_inc(instance, scmd);
        megasas_fire_cmd_fusion(instance, req_desc);
 
        if (r1_cmd)
@@ -3450,6 +3479,7 @@ megasas_complete_r1_command(struct megasas_instance *instance,
                scmd_local->SCp.ptr = NULL;
                megasas_return_cmd_fusion(instance, cmd);
                scsi_dma_unmap(scmd_local);
+               megasas_sdev_busy_dec(instance, scmd_local);
                scmd_local->scsi_done(scmd_local);
        }
 }
@@ -3550,6 +3580,7 @@ complete_cmd_fusion(struct megasas_instance *instance, u32 MSIxIndex,
                                scmd_local->SCp.ptr = NULL;
                                megasas_return_cmd_fusion(instance, cmd_fusion);
                                scsi_dma_unmap(scmd_local);
+                               megasas_sdev_busy_dec(instance, scmd_local);
                                scmd_local->scsi_done(scmd_local);
                        } else  /* Optimal VD - R1 FP command completion. */
                                megasas_complete_r1_command(instance, cmd_fusion);