Commit 893def38 authored Jun 04, 2013 by K. Y. Srinivasan Committed by James Bottomley Jun 26, 2013

[SCSI] storvsc: Increase the value of scsi timeout for storvsc devices



The standard scsi timeout is not appropriate in some of the environments where
Hyper-V is deployed. Set this timeout appropriately for all devices managed
by this driver.

On cloud environments where storage latencies may be unbounded, having the
scsi layer initiating recovery can be problematic since (a) the host is
already implementing a variety of recovery strategies and (b) implementing a
recovery strategy at the VM level may be more appropriate in cases where
storage latencies exceed a certain threshold.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

parent 1f34923c

drivers/scsi/storvsc_drv.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -221,6 +221,11 @@ static int storvsc_ringbuffer_size = (20 * PAGE_SIZE);
		module_param(storvsc_ringbuffer_size, int, S_IRUGO);
		MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");

		/*
		* Timeout in seconds for all devices managed by this driver.
		*/
		static int storvsc_timeout = 180;

		#define STORVSC_MAX_IO_REQUESTS 128

		/*
		@@ -1204,6 +1209,8 @@ static int storvsc_device_configure(struct scsi_device *sdevice)

		blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);

		blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));

		sdevice->no_write_same = 1;

		return 0;