From bd7d4ef6a4c9b3611fa487a0065bf042c71ce620 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 9 May 2018 15:25:22 -0600 Subject: [PATCH] bfq-iosched: remove unused variable bfqd->sb_shift was attempted used as a cache for the sbitmap queue shift, but we don't need it, as it never changes. Kill it with fire. Acked-by: Paolo Valente Reviewed-by: Omar Sandoval Signed-off-by: Jens Axboe --- block/bfq-iosched.c | 16 +++++++--------- block/bfq-iosched.h | 6 ------ 2 files changed, 7 insertions(+), 15 deletions(-) diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 0cd8aa80c32d..10294124d597 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -5085,26 +5085,24 @@ void bfq_put_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg) */ static void bfq_update_depths(struct bfq_data *bfqd, struct sbitmap_queue *bt) { - bfqd->sb_shift = bt->sb.shift; - /* * In-word depths if no bfq_queue is being weight-raised: * leaving 25% of tags only for sync reads. * * In next formulas, right-shift the value - * (1U<sb_shift), instead of computing directly - * (1U<<(bfqd->sb_shift - something)), to be robust against - * any possible value of bfqd->sb_shift, without having to + * (1U<sb.shift), instead of computing directly + * (1U<<(bt->sb.shift - something)), to be robust against + * any possible value of bt->sb.shift, without having to * limit 'something'. */ /* no more than 50% of tags for async I/O */ - bfqd->word_depths[0][0] = max((1U<sb_shift)>>1, 1U); + bfqd->word_depths[0][0] = max((1U << bt->sb.shift) >> 1, 1U); /* * no more than 75% of tags for sync writes (25% extra tags * w.r.t. async I/O, to prevent async I/O from starving sync * writes) */ - bfqd->word_depths[0][1] = max(((1U<sb_shift) * 3)>>2, 1U); + bfqd->word_depths[0][1] = max(((1U << bt->sb.shift) * 3) >> 2, 1U); /* * In-word depths in case some bfq_queue is being weight- @@ -5114,9 +5112,9 @@ static void bfq_update_depths(struct bfq_data *bfqd, struct sbitmap_queue *bt) * shortage. */ /* no more than ~18% of tags for async I/O */ - bfqd->word_depths[1][0] = max(((1U<sb_shift) * 3)>>4, 1U); + bfqd->word_depths[1][0] = max(((1U << bt->sb.shift) * 3) >> 4, 1U); /* no more than ~37% of tags for sync writes (~20% extra tags) */ - bfqd->word_depths[1][1] = max(((1U<sb_shift) * 6)>>4, 1U); + bfqd->word_depths[1][1] = max(((1U << bt->sb.shift) * 6) >> 4, 1U); } static int bfq_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int index) diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h index 8ec7ff92cd6f..faac509cb35e 100644 --- a/block/bfq-iosched.h +++ b/block/bfq-iosched.h @@ -635,12 +635,6 @@ struct bfq_data { /* bfqq associated with the task issuing current bio for merging */ struct bfq_queue *bio_bfqq; - /* - * Cached sbitmap shift, used to compute depth limits in - * bfq_update_depths. - */ - unsigned int sb_shift; - /* * Depth limits used in bfq_limit_depth (see comments on the * function) -- GitLab