From b8b3e16cfe6435d961f6aaebcfd52a1ff2a988c5 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Fri, 15 Aug 2008 10:15:19 +0200 Subject: block: drop virtual merging accounting Remove virtual merge accounting. Signed-off-by: Mikulas Patocka Signed-off-by: Jens Axboe --- block/blk-merge.c | 79 +++++-------------------------------------------------- 1 file changed, 6 insertions(+), 73 deletions(-) (limited to 'block') diff --git a/block/blk-merge.c b/block/blk-merge.c index 6cf8f0c70a51..2c2a2ee716ec 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -66,7 +66,7 @@ void blk_recalc_rq_segments(struct request *rq) */ high = page_to_pfn(bv->bv_page) > q->bounce_pfn; if (high || highprv) - goto new_hw_segment; + goto new_segment; if (cluster) { if (seg_size + bv->bv_len > q->max_segment_size) goto new_segment; @@ -74,8 +74,6 @@ void blk_recalc_rq_segments(struct request *rq) goto new_segment; if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bv)) goto new_segment; - if (BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len)) - goto new_hw_segment; seg_size += bv->bv_len; hw_seg_size += bv->bv_len; @@ -83,17 +81,11 @@ void blk_recalc_rq_segments(struct request *rq) continue; } new_segment: - if (BIOVEC_VIRT_MERGEABLE(bvprv, bv) && - !BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len)) - hw_seg_size += bv->bv_len; - else { -new_hw_segment: - if (nr_hw_segs == 1 && - hw_seg_size > rq->bio->bi_hw_front_size) - rq->bio->bi_hw_front_size = hw_seg_size; - hw_seg_size = BIOVEC_VIRT_START_SIZE(bv) + bv->bv_len; - nr_hw_segs++; - } + if (nr_hw_segs == 1 && + hw_seg_size > rq->bio->bi_hw_front_size) + rq->bio->bi_hw_front_size = hw_seg_size; + hw_seg_size = bv->bv_len; + nr_hw_segs++; nr_phys_segs++; bvprv = bv; @@ -150,23 +142,6 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, return 0; } -static int blk_hw_contig_segment(struct request_queue *q, struct bio *bio, - struct bio *nxt) -{ - if (!bio_flagged(bio, BIO_SEG_VALID)) - blk_recount_segments(q, bio); - if (!bio_flagged(nxt, BIO_SEG_VALID)) - blk_recount_segments(q, nxt); - if (bio_has_data(bio) && - (!BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)) || - BIOVEC_VIRT_OVERSIZE(bio->bi_hw_back_size + nxt->bi_hw_front_size))) - return 0; - if (bio->bi_hw_back_size + nxt->bi_hw_front_size > q->max_segment_size) - return 0; - - return 1; -} - /* * map a request to scatterlist, return number of sg entries setup. Caller * must make sure sg can hold rq->nr_phys_segments entries @@ -304,7 +279,6 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req, struct bio *bio) { unsigned short max_sectors; - int len; if (unlikely(blk_pc_request(req))) max_sectors = q->max_hw_sectors; @@ -321,20 +295,6 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req, blk_recount_segments(q, req->biotail); if (!bio_flagged(bio, BIO_SEG_VALID)) blk_recount_segments(q, bio); - len = req->biotail->bi_hw_back_size + bio->bi_hw_front_size; - if (!bio_has_data(bio) || - (BIOVEC_VIRT_MERGEABLE(__BVEC_END(req->biotail), __BVEC_START(bio)) - && !BIOVEC_VIRT_OVERSIZE(len))) { - int mergeable = ll_new_mergeable(q, req, bio); - - if (mergeable) { - if (req->nr_hw_segments == 1) - req->bio->bi_hw_front_size = len; - if (bio->bi_hw_segments == 1) - bio->bi_hw_back_size = len; - } - return mergeable; - } return ll_new_hw_segment(q, req, bio); } @@ -343,7 +303,6 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req, struct bio *bio) { unsigned short max_sectors; - int len; if (unlikely(blk_pc_request(req))) max_sectors = q->max_hw_sectors; @@ -357,24 +316,10 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req, q->last_merge = NULL; return 0; } - len = bio->bi_hw_back_size + req->bio->bi_hw_front_size; if (!bio_flagged(bio, BIO_SEG_VALID)) blk_recount_segments(q, bio); if (!bio_flagged(req->bio, BIO_SEG_VALID)) blk_recount_segments(q, req->bio); - if (!bio_has_data(bio) || - (BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(req->bio)) && - !BIOVEC_VIRT_OVERSIZE(len))) { - int mergeable = ll_new_mergeable(q, req, bio); - - if (mergeable) { - if (bio->bi_hw_segments == 1) - bio->bi_hw_front_size = len; - if (req->nr_hw_segments == 1) - req->biotail->bi_hw_back_size = len; - } - return mergeable; - } return ll_new_hw_segment(q, req, bio); } @@ -406,18 +351,6 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, return 0; total_hw_segments = req->nr_hw_segments + next->nr_hw_segments; - if (blk_hw_contig_segment(q, req->biotail, next->bio)) { - int len = req->biotail->bi_hw_back_size + - next->bio->bi_hw_front_size; - /* - * propagate the combined length to the end of the requests - */ - if (req->nr_hw_segments == 1) - req->bio->bi_hw_front_size = len; - if (next->nr_hw_segments == 1) - next->biotail->bi_hw_back_size = len; - total_hw_segments--; - } if (total_hw_segments > q->max_hw_segments) return 0; -- cgit v1.2.3-58-ga151