diff options
Diffstat (limited to 'block/blk-wbt.c')
| -rw-r--r-- | block/blk-wbt.c | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/block/blk-wbt.c b/block/blk-wbt.c index 6dfc659d22e2..f1754d07f7e0 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -136,8 +136,9 @@ enum { RWB_MIN_WRITE_SAMPLES = 3, /* - * If we have this number of consecutive windows with not enough - * information to scale up or down, scale up. + * If we have this number of consecutive windows without enough + * information to scale up or down, slowly return to center state + * (step == 0). */ RWB_UNKNOWN_BUMP = 5, }; @@ -446,9 +447,9 @@ static void wb_timer_fn(struct blk_stat_callback *cb) break; case LAT_UNKNOWN_WRITES: /* - * We started a the center step, but don't have a valid - * read/write sample, but we do have writes going on. - * Allow step to go negative, to increase write perf. + * We don't have a valid read/write sample, but we do have + * writes going on. Allow step to go negative, to increase + * write performance. */ scale_up(rwb); break; @@ -638,11 +639,7 @@ static void wbt_cleanup(struct rq_qos *rqos, struct bio *bio) __wbt_done(rqos, flags); } -/* - * May sleep, if we have exceeded the writeback limits. Caller can pass - * in an irq held spinlock, if it holds one when calling this function. - * If we do sleep, we'll release and re-grab it. - */ +/* May sleep, if we have exceeded the writeback limits. */ static void wbt_wait(struct rq_qos *rqos, struct bio *bio) { struct rq_wb *rwb = RQWB(rqos); |