scsi: hisi_sas: Run I_T nexus resets in parallel for clear nexus reset

For a clear nexus reset operation, the I_T nexus resets are executed
serially for each device. For devices attached through an expander, this
may take 2s per device; so, in total, could take a long time.

Reduce the total time by running the I_T nexus resets in parallel through
async operations.

Link: https://lore.kernel.org/r/1623058179-80434-3-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index 8e36ede..fbecdf7 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -8,6 +8,7 @@
 #define _HISI_SAS_H_
 
 #include <linux/acpi.h>
+#include <linux/async.h>
 #include <linux/blk-mq.h>
 #include <linux/blk-mq-pci.h>
 #include <linux/clk.h>

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 5042074..856cdc1 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -1886,12 +1886,24 @@ out:
        return rc;
 }
 
+static void hisi_sas_async_I_T_nexus_reset(void *data, async_cookie_t cookie)
+{
+       struct domain_device *device = data;
+       struct hisi_hba *hisi_hba = dev_to_hisi_hba(device);
+       int rc;
+
+       rc = hisi_sas_debug_I_T_nexus_reset(device);
+       if (rc != TMF_RESP_FUNC_COMPLETE)
+               dev_info(hisi_hba->dev, "I_T_nexus reset fail for dev:%016llx rc=%d\n",
+                        SAS_ADDR(device->sas_addr), rc);
+}
+
 static int hisi_sas_clear_nexus_ha(struct sas_ha_struct *sas_ha)
 {
        struct hisi_hba *hisi_hba = sas_ha->lldd_ha;
-       struct device *dev = hisi_hba->dev;
        HISI_SAS_DECLARE_RST_WORK_ON_STACK(r);
-       int rc, i;
+       ASYNC_DOMAIN_EXCLUSIVE(async);
+       int i;
 
        queue_work(hisi_hba->wq, &r.work);
        wait_for_completion(r.completion);
@@ -1906,12 +1918,11 @@ static int hisi_sas_clear_nexus_ha(struct sas_ha_struct *sas_ha)
                    dev_is_expander(device->dev_type))
                        continue;
 
-               rc = hisi_sas_debug_I_T_nexus_reset(device);
-               if (rc != TMF_RESP_FUNC_COMPLETE)
-                       dev_info(dev, "clear nexus ha: for device[%d] rc=%d\n",
-                                sas_dev->device_id, rc);
+               async_schedule_domain(hisi_sas_async_I_T_nexus_reset,
+                                     device, &async);
        }
 
+       async_synchronize_full_domain(&async);
        hisi_sas_release_tasks(hisi_hba);
 
        return TMF_RESP_FUNC_COMPLETE;