NVMe: Avoid shift operation when writing cq head doorbell

Changes the type of dev->db_stride to unsigned and changes the value
stored there to be 1 << the current value. Then there is less
calculation to be done at completion time.

Signed-off-by: Haiyan Hu <huhaiyan@huawei.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 26ebcf41c213..8119a476cb29 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -80,7 +80,7 @@ struct nvme_dev {
         struct dma_pool *prp_small_pool;
         int instance;
         int queue_count;
-        int db_stride;
+        u32 db_stride;
         u32 ctrl_config;
         struct msix_entry *entry;
         struct nvme_bar __iomem *bar;