blk-wbt: make enable_state more accurate

Currently, if user disable wbt through sysfs, 'enable_state' will be
'WBT_STATE_ON_MANUAL', which will be confusing. Add a new state
'WBT_STATE_OFF_MANUAL' to cover that case.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index c5a8c10..4680691 100644 (file)
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -435,8 +435,13 @@ void wbt_set_min_lat(struct request_queue *q, u64 val)
        struct rq_qos *rqos = wbt_rq_qos(q);
        if (!rqos)
                return;
+
        RQWB(rqos)->min_lat_nsec = val;
-       RQWB(rqos)->enable_state = WBT_STATE_ON_MANUAL;
+       if (val)
+               RQWB(rqos)->enable_state = WBT_STATE_ON_MANUAL;
+       else
+               RQWB(rqos)->enable_state = WBT_STATE_OFF_MANUAL;
+
        wbt_update_limits(RQWB(rqos));
 }
 

diff --git a/block/blk-wbt.h b/block/blk-wbt.h
index 7e44ecc..7fe9863 100644 (file)
--- a/block/blk-wbt.h
+++ b/block/blk-wbt.h
@@ -28,13 +28,15 @@ enum {
 };
 
 /*
- * Enable states. Either off, or on by default (done at init time),
- * or on through manual setup in sysfs.
+ * If current state is WBT_STATE_ON/OFF_DEFAULT, it can be covered to any other
+ * state, if current state is WBT_STATE_ON/OFF_MANUAL, it can only be covered
+ * to WBT_STATE_OFF/ON_MANUAL.
  */
 enum {
-       WBT_STATE_ON_DEFAULT    = 1,
-       WBT_STATE_ON_MANUAL     = 2,
-       WBT_STATE_OFF_DEFAULT
+       WBT_STATE_ON_DEFAULT    = 1,    /* on by default */
+       WBT_STATE_ON_MANUAL     = 2,    /* on manually by sysfs */
+       WBT_STATE_OFF_DEFAULT   = 3,    /* off by default */
+       WBT_STATE_OFF_MANUAL    = 4,    /* off manually by sysfs */
 };
 
 struct rq_wb {