From 80e091d10e8bf7b801d634ea8870b9e907314424 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 28 Nov 2016 09:22:47 -0700 Subject: blk-wbt: allow reset of default latency through sysfs Allow a write of '-1' to reset the default latency target for a given device. This removes knowledge of the different default settings for rotational vs non-rotational from user space. Signed-off-by: Jens Axboe --- Documentation/block/queue-sysfs.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt index 14235e72a702..51642159aedb 100644 --- a/Documentation/block/queue-sysfs.txt +++ b/Documentation/block/queue-sysfs.txt @@ -188,7 +188,9 @@ wb_lat_usec (RW) If the device is registered for writeback throttling, then this file shows the target minimum read latency. If this latency is exceeded in a given window of time (see wb_window_usec), then the writeback throttling will start -scaling back writes. +scaling back writes. Writing a value of '0' to this file disables the +feature. Writing a value of '-1' to this file resets the value to the +default setting. Jens Axboe , February 2009 -- cgit v1.2.3