[PATCH v4] block: add documentation for io_timeout

[PATCH v4] block: add documentation for io_timeout

[Weiping Zhang]

Add documentation for /sys/block/<disk>/queue/io_timeout.

Signed-off-by: Weiping Zhang <zhangweiping@didiglobal.com>
---
 Documentation/ABI/testing/sysfs-block | 9 +++++++++
 Documentation/block/queue-sysfs.txt   | 7 +++++++
 2 files changed, 16 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index 7710d4022b19..dfad7427817c 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -279,3 +279,12 @@ Description:
 		size in 512B sectors of the zones of the device, with
 		the eventual exception of the last zone of the device
 		which may be smaller.
+
+What:		/sys/block/<disk>/queue/io_timeout
+Date:		November 2018
+Contact:	Weiping Zhang <zhangweiping@didiglobal.com>
+Description:
+		io_timeout is the request timeout in milliseconds. If a request
+		does not complete in this time then the block driver timeout
+		handler is invoked. That timeout handler can decide to retry
+		the request, to fail it or to start a device recovery strategy.
diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt
index 39e286d7afc9..83b457e24bba 100644
--- a/Documentation/block/queue-sysfs.txt
+++ b/Documentation/block/queue-sysfs.txt
@@ -67,6 +67,13 @@ If set to a value larger than 0, the kernel will put the process issuing
 IO to sleep for this amount of microseconds before entering classic
 polling.
 
+io_timeout (RW)
+---------------
+io_timeout is the request timeout in milliseconds. If a request does not
+complete in this time then the block driver timeout handler is invoked.
+That timeout handler can decide to retry the request, to fail it or to start
+a device recovery strategy.
+
 iostats (RW)
 -------------
 This file is used to control (on/off) the iostats accounting of the
-- 
2.14.1

Re: [PATCH v4] block: add documentation for io_timeout

[Bart Van Assche]

On Wed, 2018-12-26 at 11:56 +0800, Weiping Zhang wrote:
> Add documentation for /sys/block/<disk>/queue/io_timeout.
> 
> Signed-off-by: Weiping Zhang <zhangweiping@didiglobal.com>
> ---
>  Documentation/ABI/testing/sysfs-block | 9 +++++++++
>  Documentation/block/queue-sysfs.txt   | 7 +++++++
>  2 files changed, 16 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
> index 7710d4022b19..dfad7427817c 100644
> --- a/Documentation/ABI/testing/sysfs-block
> +++ b/Documentation/ABI/testing/sysfs-block
> @@ -279,3 +279,12 @@ Description:
>  		size in 512B sectors of the zones of the device, with
>  		the eventual exception of the last zone of the device
>  		which may be smaller.
> +
> +What:		/sys/block/<disk>/queue/io_timeout
> +Date:		November 2018
> +Contact:	Weiping Zhang <zhangweiping@didiglobal.com>
> +Description:
> +		io_timeout is the request timeout in milliseconds. If a request
> +		does not complete in this time then the block driver timeout
> +		handler is invoked. That timeout handler can decide to retry
> +		the request, to fail it or to start a device recovery strategy.
> diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt
> index 39e286d7afc9..83b457e24bba 100644
> --- a/Documentation/block/queue-sysfs.txt
> +++ b/Documentation/block/queue-sysfs.txt
> @@ -67,6 +67,13 @@ If set to a value larger than 0, the kernel will put the process issuing
>  IO to sleep for this amount of microseconds before entering classic
>  polling.
>  
> +io_timeout (RW)
> +---------------
> +io_timeout is the request timeout in milliseconds. If a request does not
> +complete in this time then the block driver timeout handler is invoked.
> +That timeout handler can decide to retry the request, to fail it or to start
> +a device recovery strategy.
> +
>  iostats (RW)
>  -------------
>  This file is used to control (on/off) the iostats accounting of the

Reviewed-by: Bart Van Assche <bvanassche@acm.org>

Re: [PATCH v4] block: add documentation for io_timeout

[Jens Axboe]

On 12/25/18 8:56 PM, Weiping Zhang wrote:
> Add documentation for /sys/block/<disk>/queue/io_timeout.

Applied, thanks.

-- 
Jens Axboe