diff options
| -rw-r--r-- | block/blk-sysfs.c | 22 | ||||
| -rw-r--r-- | block/blk-wbt.c | 3 | ||||
| -rw-r--r-- | block/blk-wbt.h | 11 |
3 files changed, 29 insertions, 7 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index f0ca569e276b..a97841491769 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -425,20 +425,30 @@ static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, ssize_t ret; s64 val; - rwb = q->rq_wb; - if (!rwb) - return -EINVAL; - ret = queue_var_store64(&val, page); if (ret < 0) return ret; + if (val < -1) + return -EINVAL; + + rwb = q->rq_wb; + if (!rwb) { + ret = wbt_init(q); + if (ret) + return ret; + + rwb = q->rq_wb; + if (!rwb) + return -EINVAL; + } if (val == -1) rwb->min_lat_nsec = wbt_default_latency_nsec(q); else if (val >= 0) rwb->min_lat_nsec = val * 1000ULL; - else - return -EINVAL; + + if (rwb->enable_state == WBT_STATE_ON_DEFAULT) + rwb->enable_state = WBT_STATE_ON_MANUAL; wbt_update_limits(rwb); return count; diff --git a/block/blk-wbt.c b/block/blk-wbt.c index 7c0e618d6e7d..b8647343141f 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -673,7 +673,7 @@ void wbt_disable_default(struct request_queue *q) { struct rq_wb *rwb = q->rq_wb; - if (rwb) { + if (rwb && rwb->enable_state == WBT_STATE_ON_DEFAULT) { del_timer_sync(&rwb->window_timer); rwb->win_nsec = rwb->min_lat_nsec = 0; wbt_update_limits(rwb); @@ -721,6 +721,7 @@ int wbt_init(struct request_queue *q) rwb->last_comp = rwb->last_issue = jiffies; rwb->queue = q; rwb->win_nsec = RWB_WINDOW_NSEC; + rwb->enable_state = WBT_STATE_ON_DEFAULT; wbt_update_limits(rwb); /* diff --git a/block/blk-wbt.h b/block/blk-wbt.h index 8f485f8e1baf..65f1de519f67 100644 --- a/block/blk-wbt.h +++ b/block/blk-wbt.h @@ -21,6 +21,15 @@ enum { WBT_NUM_RWQ = 2, }; +/* + * Enable states. Either off, or on by default (done at init time), + * or on through manual setup in sysfs. + */ +enum { + WBT_STATE_ON_DEFAULT = 1, + WBT_STATE_ON_MANUAL = 2, +}; + static inline void wbt_clear_state(struct blk_issue_stat *stat) { stat->time &= BLK_STAT_TIME_MASK; @@ -61,6 +70,8 @@ struct rq_wb { int scale_step; bool scaled_max; + short enable_state; /* WBT_STATE_* */ + /* * Number of consecutive periods where we don't have enough * information to make a firm scale up/down decision. |