NVMe: Increase the max transfer size when mdts is 0
authorSathyavathi M <[email protected]>
Thu, 5 Nov 2015 19:52:28 +0000 (12:52 -0700)
committerJens Axboe <[email protected]>
Wed, 11 Nov 2015 16:36:56 +0000 (09:36 -0700)
This patch address the issue when IO with 128KB from FIO is split into
two parts, 124KB and 4KB, due to max transfer size(127KB). This degrades
the device performance.

Signed-off-by: Sathyavathi M <[email protected]>
Acked-by: Keith Busch <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
drivers/nvme/host/pci.c

index 3dfc28875cc31338be0c33ff040185d03302a3b7..cb89789df40c495b3b7e9d0d2a561a366e18a664 100644 (file)
@@ -2622,6 +2622,8 @@ static int nvme_dev_add(struct nvme_dev *dev)
        memcpy(dev->firmware_rev, ctrl->fr, sizeof(ctrl->fr));
        if (ctrl->mdts)
                dev->max_hw_sectors = 1 << (ctrl->mdts + shift - 9);
+       else
+               dev->max_hw_sectors = UINT_MAX;
        if ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
                        (pdev->device == 0x0953) && ctrl->vs[3]) {
                unsigned int max_hw_sectors;