blk-wbt: use BLK_STAT_{READ,WRITE} instead of 0/1

Since we have proper enums for the stats directions, use them.

Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index f6ec7e587fa605a515469caa6d23d2e3632bed73..20712f0db6eab03a7d8d3271e29bfe111e678722 100644 (file)
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -255,8 +255,8 @@ static bool inline stat_sample_valid(struct blk_rq_stat *stat)
         * that it's writes impacting us, and not just some sole read on
         * a device that is in a lower power state.
         */
-       return stat[0].nr_samples >= 1 &&
-               stat[1].nr_samples >= RWB_MIN_WRITE_SAMPLES;
+       return stat[BLK_STAT_READ].nr_samples >= 1 &&
+               stat[BLK_STAT_WRITE].nr_samples >= RWB_MIN_WRITE_SAMPLES;
 }
 
 static u64 rwb_sync_issue_lat(struct rq_wb *rwb)
@@ -293,7 +293,7 @@ static int __latency_exceeded(struct rq_wb *rwb, struct blk_rq_stat *stat)
         */
        thislat = rwb_sync_issue_lat(rwb);
        if (thislat > rwb->cur_win_nsec ||
-           (thislat > rwb->min_lat_nsec && !stat[0].nr_samples)) {
+           (thislat > rwb->min_lat_nsec && !stat[BLK_STAT_READ].nr_samples)) {
                trace_wbt_lat(bdi, thislat);
                return LAT_EXCEEDED;
        }
@@ -308,7 +308,7 @@ static int __latency_exceeded(struct rq_wb *rwb, struct blk_rq_stat *stat)
                 * waited or still has writes in flights, consider us doing
                 * just writes as well.
                 */
-               if ((stat[1].nr_samples && blk_stat_is_current(stat)) ||
+               if ((stat[BLK_STAT_WRITE].nr_samples && blk_stat_is_current(stat)) ||
                    wb_recent_wait(rwb) || wbt_inflight(rwb))
                        return LAT_UNKNOWN_WRITES;
                return LAT_UNKNOWN;
@@ -317,8 +317,8 @@ static int __latency_exceeded(struct rq_wb *rwb, struct blk_rq_stat *stat)
        /*
         * If the 'min' latency exceeds our target, step down.
         */
-       if (stat[0].min > rwb->min_lat_nsec) {
-               trace_wbt_lat(bdi, stat[0].min);
+       if (stat[BLK_STAT_READ].min > rwb->min_lat_nsec) {
+               trace_wbt_lat(bdi, stat[BLK_STAT_READ].min);
                trace_wbt_stat(bdi, stat);
                return LAT_EXCEEDED;
        }