scsi: megaraid_sas: add correct return type check for ldio hint logic for raid1

Return value check of atomic_dec_if_positive is required as it returns
old value minus one.  Without this fix, driver will send small ios to
firmware path and that will be a performance issue.

Not critical, but good to have r1_ldio_hint as default value in sdev
private.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@broadcom.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 016ffcebaf66bd2d43c7d77f03ba8173ed5fba94..0016f12cc563e7c6e1eb3c2a87685f60c83b9747 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -1963,6 +1963,9 @@ scan_target:
        if (!mr_device_priv_data)
                return -ENOMEM;
        sdev->hostdata = mr_device_priv_data;
+
+       atomic_set(&mr_device_priv_data->r1_ldio_hint,
+                  instance->r1_ldio_hint_default);
        return 0;
 }
 

diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index 29650ba669da58da099cf91e9de0aae504146bb0..ebd746e2d97cb0bc63bdd5342bca5f6588ac5a44 100644 (file)
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -2338,7 +2338,7 @@ megasas_build_ldio_fusion(struct megasas_instance *instance,
                                fp_possible = false;
                                atomic_dec(&instance->fw_outstanding);
                        } else if ((scsi_buff_len > MR_LARGE_IO_MIN_SIZE) ||
-                                  atomic_dec_if_positive(&mrdev_priv->r1_ldio_hint)) {
+                                  (atomic_dec_if_positive(&mrdev_priv->r1_ldio_hint) > 0)) {
                                fp_possible = false;
                                atomic_dec(&instance->fw_outstanding);
                                if (scsi_buff_len > MR_LARGE_IO_MIN_SIZE)