From 85496749904016f36b69332f73a1cf3ecfee828f Mon Sep 17 00:00:00 2001 From: Yu Kuai Date: Wed, 21 Sep 2022 17:53:08 +0800 Subject: [PATCH] blk-throttle: remove THROTL_TG_HAS_IOPS_LIMIT Currently, "tg->has_rules" and "tg->flags & THROTL_TG_HAS_IOPS_LIMIT" both try to bypass bios that don't need to be throttled, however, they are a little redundant and both not perfect: 1) "tg->has_rules" only distinguish read and write, but not iops and bps limit. 2) "tg->flags & THROTL_TG_HAS_IOPS_LIMIT" only check if iops limit exist, read and write is not distinguished, and bps limit is not checked. tg->has_rules will extended to distinguish bps and iops in the following patch. There is no need to keep the flag. Signed-off-by: Yu Kuai Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20220921095309.1481289-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe --- block/blk-throttle.c | 16 ++-------------- block/blk-throttle.h | 8 +------- 2 files changed, 3 insertions(+), 21 deletions(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 55f2d985cfbb..a062539d84d0 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -420,24 +420,12 @@ static void tg_update_has_rules(struct throtl_grp *tg) struct throtl_grp *parent_tg = sq_to_tg(tg->service_queue.parent_sq); struct throtl_data *td = tg->td; int rw; - int has_iops_limit = 0; - - for (rw = READ; rw <= WRITE; rw++) { - unsigned int iops_limit = tg_iops_limit(tg, rw); + for (rw = READ; rw <= WRITE; rw++) tg->has_rules[rw] = (parent_tg && parent_tg->has_rules[rw]) || (td->limit_valid[td->limit_index] && (tg_bps_limit(tg, rw) != U64_MAX || - iops_limit != UINT_MAX)); - - if (iops_limit != UINT_MAX) - has_iops_limit = 1; - } - - if (has_iops_limit) - tg->flags |= THROTL_TG_HAS_IOPS_LIMIT; - else - tg->flags &= ~THROTL_TG_HAS_IOPS_LIMIT; + tg_iops_limit(tg, rw) != UINT_MAX)); } static void throtl_pd_online(struct blkg_policy_data *pd) diff --git a/block/blk-throttle.h b/block/blk-throttle.h index 66b4292b1b92..3994b89dfa11 100644 --- a/block/blk-throttle.h +++ b/block/blk-throttle.h @@ -55,8 +55,7 @@ struct throtl_service_queue { enum tg_state_flags { THROTL_TG_PENDING = 1 << 0, /* on parent's pending tree */ THROTL_TG_WAS_EMPTY = 1 << 1, /* bio_lists[] became non-empty */ - THROTL_TG_HAS_IOPS_LIMIT = 1 << 2, /* tg has iops limit */ - THROTL_TG_CANCELING = 1 << 3, /* starts to cancel bio */ + THROTL_TG_CANCELING = 1 << 2, /* starts to cancel bio */ }; enum { @@ -183,11 +182,6 @@ static inline bool blk_throtl_bio(struct bio *bio) { struct throtl_grp *tg = blkg_to_tg(bio->bi_blkg); - /* no need to throttle bps any more if the bio has been throttled */ - if (bio_flagged(bio, BIO_BPS_THROTTLED) && - !(tg->flags & THROTL_TG_HAS_IOPS_LIMIT)) - return false; - if (!tg->has_rules[bio_data_dir(bio)]) return false;