From 9f626e372a602486fa319c2c6ab18e8068b30094 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Mon, 27 Mar 2017 10:51:30 -0700 Subject: blk-throttle: prepare support multiple limits We are going to support low/max limit, each cgroup will have 2 limits after that. This patch prepares for the multiple limits change. Signed-off-by: Shaohua Li Signed-off-by: Jens Axboe --- block/blk-throttle.c | 110 ++++++++++++++++++++++++++++++++------------------- 1 file changed, 70 insertions(+), 40 deletions(-) (limited to 'block/blk-throttle.c') diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 0d5d85ba25ea3..1da9f30cc3d10 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -83,6 +83,11 @@ enum tg_state_flags { #define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node) +enum { + LIMIT_MAX, + LIMIT_CNT, +}; + struct throtl_grp { /* must be the first member */ struct blkg_policy_data pd; @@ -120,10 +125,10 @@ struct throtl_grp { bool has_rules[2]; /* bytes per second rate limits */ - uint64_t bps[2]; + uint64_t bps[2][LIMIT_CNT]; /* IOPS limits */ - unsigned int iops[2]; + unsigned int iops[2][LIMIT_CNT]; /* Number of bytes disptached in current slice */ uint64_t bytes_disp[2]; @@ -147,6 +152,8 @@ struct throtl_data /* Work for dispatching throttled bios */ struct work_struct dispatch_work; + unsigned int limit_index; + bool limit_valid[LIMIT_CNT]; }; static void throtl_pending_timer_fn(unsigned long arg); @@ -198,6 +205,16 @@ static struct throtl_data *sq_to_td(struct throtl_service_queue *sq) return container_of(sq, struct throtl_data, service_queue); } +static uint64_t tg_bps_limit(struct throtl_grp *tg, int rw) +{ + return tg->bps[rw][tg->td->limit_index]; +} + +static unsigned int tg_iops_limit(struct throtl_grp *tg, int rw) +{ + return tg->iops[rw][tg->td->limit_index]; +} + /** * throtl_log - log debug message via blktrace * @sq: the service_queue being reported @@ -334,10 +351,10 @@ static struct blkg_policy_data *throtl_pd_alloc(gfp_t gfp, int node) } RB_CLEAR_NODE(&tg->rb_node); - tg->bps[READ] = U64_MAX; - tg->bps[WRITE] = U64_MAX; - tg->iops[READ] = UINT_MAX; - tg->iops[WRITE] = UINT_MAX; + tg->bps[READ][LIMIT_MAX] = U64_MAX; + tg->bps[WRITE][LIMIT_MAX] = U64_MAX; + tg->iops[READ][LIMIT_MAX] = UINT_MAX; + tg->iops[WRITE][LIMIT_MAX] = UINT_MAX; return &tg->pd; } @@ -376,11 +393,14 @@ static void throtl_pd_init(struct blkg_policy_data *pd) 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; for (rw = READ; rw <= WRITE; rw++) tg->has_rules[rw] = (parent_tg && parent_tg->has_rules[rw]) || - (tg->bps[rw] != U64_MAX || tg->iops[rw] != UINT_MAX); + (td->limit_valid[td->limit_index] && + (tg_bps_limit(tg, rw) != U64_MAX || + tg_iops_limit(tg, rw) != UINT_MAX)); } static void throtl_pd_online(struct blkg_policy_data *pd) @@ -632,11 +652,11 @@ static inline void throtl_trim_slice(struct throtl_grp *tg, bool rw) if (!nr_slices) return; - tmp = tg->bps[rw] * throtl_slice * nr_slices; + tmp = tg_bps_limit(tg, rw) * throtl_slice * nr_slices; do_div(tmp, HZ); bytes_trim = tmp; - io_trim = (tg->iops[rw] * throtl_slice * nr_slices)/HZ; + io_trim = (tg_iops_limit(tg, rw) * throtl_slice * nr_slices) / HZ; if (!bytes_trim && !io_trim) return; @@ -682,7 +702,7 @@ static bool tg_with_in_iops_limit(struct throtl_grp *tg, struct bio *bio, * have been trimmed. */ - tmp = (u64)tg->iops[rw] * jiffy_elapsed_rnd; + tmp = (u64)tg_iops_limit(tg, rw) * jiffy_elapsed_rnd; do_div(tmp, HZ); if (tmp > UINT_MAX) @@ -697,7 +717,7 @@ static bool tg_with_in_iops_limit(struct throtl_grp *tg, struct bio *bio, } /* Calc approx time to dispatch */ - jiffy_wait = ((tg->io_disp[rw] + 1) * HZ)/tg->iops[rw] + 1; + jiffy_wait = ((tg->io_disp[rw] + 1) * HZ) / tg_iops_limit(tg, rw) + 1; if (jiffy_wait > jiffy_elapsed) jiffy_wait = jiffy_wait - jiffy_elapsed; @@ -724,7 +744,7 @@ static bool tg_with_in_bps_limit(struct throtl_grp *tg, struct bio *bio, jiffy_elapsed_rnd = roundup(jiffy_elapsed_rnd, throtl_slice); - tmp = tg->bps[rw] * jiffy_elapsed_rnd; + tmp = tg_bps_limit(tg, rw) * jiffy_elapsed_rnd; do_div(tmp, HZ); bytes_allowed = tmp; @@ -736,7 +756,7 @@ static bool tg_with_in_bps_limit(struct throtl_grp *tg, struct bio *bio, /* Calc approx time to dispatch */ extra_bytes = tg->bytes_disp[rw] + bio->bi_iter.bi_size - bytes_allowed; - jiffy_wait = div64_u64(extra_bytes * HZ, tg->bps[rw]); + jiffy_wait = div64_u64(extra_bytes * HZ, tg_bps_limit(tg, rw)); if (!jiffy_wait) jiffy_wait = 1; @@ -771,7 +791,8 @@ static bool tg_may_dispatch(struct throtl_grp *tg, struct bio *bio, bio != throtl_peek_queued(&tg->service_queue.queued[rw])); /* If tg->bps = -1, then BW is unlimited */ - if (tg->bps[rw] == U64_MAX && tg->iops[rw] == UINT_MAX) { + if (tg_bps_limit(tg, rw) == U64_MAX && + tg_iops_limit(tg, rw) == UINT_MAX) { if (wait) *wait = 0; return true; @@ -1150,8 +1171,8 @@ static void tg_conf_updated(struct throtl_grp *tg) throtl_log(&tg->service_queue, "limit change rbps=%llu wbps=%llu riops=%u wiops=%u", - tg->bps[READ], tg->bps[WRITE], - tg->iops[READ], tg->iops[WRITE]); + tg_bps_limit(tg, READ), tg_bps_limit(tg, WRITE), + tg_iops_limit(tg, READ), tg_iops_limit(tg, WRITE)); /* * Update has_rules[] flags for the updated tg's subtree. A tg is @@ -1228,25 +1249,25 @@ static ssize_t tg_set_conf_uint(struct kernfs_open_file *of, static struct cftype throtl_legacy_files[] = { { .name = "throttle.read_bps_device", - .private = offsetof(struct throtl_grp, bps[READ]), + .private = offsetof(struct throtl_grp, bps[READ][LIMIT_MAX]), .seq_show = tg_print_conf_u64, .write = tg_set_conf_u64, }, { .name = "throttle.write_bps_device", - .private = offsetof(struct throtl_grp, bps[WRITE]), + .private = offsetof(struct throtl_grp, bps[WRITE][LIMIT_MAX]), .seq_show = tg_print_conf_u64, .write = tg_set_conf_u64, }, { .name = "throttle.read_iops_device", - .private = offsetof(struct throtl_grp, iops[READ]), + .private = offsetof(struct throtl_grp, iops[READ][LIMIT_MAX]), .seq_show = tg_print_conf_uint, .write = tg_set_conf_uint, }, { .name = "throttle.write_iops_device", - .private = offsetof(struct throtl_grp, iops[WRITE]), + .private = offsetof(struct throtl_grp, iops[WRITE][LIMIT_MAX]), .seq_show = tg_print_conf_uint, .write = tg_set_conf_uint, }, @@ -1272,18 +1293,25 @@ static u64 tg_prfill_max(struct seq_file *sf, struct blkg_policy_data *pd, if (!dname) return 0; - if (tg->bps[READ] == U64_MAX && tg->bps[WRITE] == U64_MAX && - tg->iops[READ] == UINT_MAX && tg->iops[WRITE] == UINT_MAX) + + if (tg->bps[READ][LIMIT_MAX] == U64_MAX && + tg->bps[WRITE][LIMIT_MAX] == U64_MAX && + tg->iops[READ][LIMIT_MAX] == UINT_MAX && + tg->iops[WRITE][LIMIT_MAX] == UINT_MAX) return 0; - if (tg->bps[READ] != U64_MAX) - snprintf(bufs[0], sizeof(bufs[0]), "%llu", tg->bps[READ]); - if (tg->bps[WRITE] != U64_MAX) - snprintf(bufs[1], sizeof(bufs[1]), "%llu", tg->bps[WRITE]); - if (tg->iops[READ] != UINT_MAX) - snprintf(bufs[2], sizeof(bufs[2]), "%u", tg->iops[READ]); - if (tg->iops[WRITE] != UINT_MAX) - snprintf(bufs[3], sizeof(bufs[3]), "%u", tg->iops[WRITE]); + if (tg->bps[READ][LIMIT_MAX] != U64_MAX) + snprintf(bufs[0], sizeof(bufs[0]), "%llu", + tg->bps[READ][LIMIT_MAX]); + if (tg->bps[WRITE][LIMIT_MAX] != U64_MAX) + snprintf(bufs[1], sizeof(bufs[1]), "%llu", + tg->bps[WRITE][LIMIT_MAX]); + if (tg->iops[READ][LIMIT_MAX] != UINT_MAX) + snprintf(bufs[2], sizeof(bufs[2]), "%u", + tg->iops[READ][LIMIT_MAX]); + if (tg->iops[WRITE][LIMIT_MAX] != UINT_MAX) + snprintf(bufs[3], sizeof(bufs[3]), "%u", + tg->iops[WRITE][LIMIT_MAX]); seq_printf(sf, "%s rbps=%s wbps=%s riops=%s wiops=%s\n", dname, bufs[0], bufs[1], bufs[2], bufs[3]); @@ -1312,10 +1340,10 @@ static ssize_t tg_set_max(struct kernfs_open_file *of, tg = blkg_to_tg(ctx.blkg); - v[0] = tg->bps[READ]; - v[1] = tg->bps[WRITE]; - v[2] = tg->iops[READ]; - v[3] = tg->iops[WRITE]; + v[0] = tg->bps[READ][LIMIT_MAX]; + v[1] = tg->bps[WRITE][LIMIT_MAX]; + v[2] = tg->iops[READ][LIMIT_MAX]; + v[3] = tg->iops[WRITE][LIMIT_MAX]; while (true) { char tok[27]; /* wiops=18446744073709551616 */ @@ -1352,10 +1380,10 @@ static ssize_t tg_set_max(struct kernfs_open_file *of, goto out_finish; } - tg->bps[READ] = v[0]; - tg->bps[WRITE] = v[1]; - tg->iops[READ] = v[2]; - tg->iops[WRITE] = v[3]; + tg->bps[READ][LIMIT_MAX] = v[0]; + tg->bps[WRITE][LIMIT_MAX] = v[1]; + tg->iops[READ][LIMIT_MAX] = v[2]; + tg->iops[WRITE][LIMIT_MAX] = v[3]; tg_conf_updated(tg); ret = 0; @@ -1453,8 +1481,9 @@ bool blk_throtl_bio(struct request_queue *q, struct blkcg_gq *blkg, /* out-of-limit, queue to @tg */ throtl_log(sq, "[%c] bio. bdisp=%llu sz=%u bps=%llu iodisp=%u iops=%u queued=%d/%d", rw == READ ? 'R' : 'W', - tg->bytes_disp[rw], bio->bi_iter.bi_size, tg->bps[rw], - tg->io_disp[rw], tg->iops[rw], + tg->bytes_disp[rw], bio->bi_iter.bi_size, + tg_bps_limit(tg, rw), + tg->io_disp[rw], tg_iops_limit(tg, rw), sq->nr_queued[READ], sq->nr_queued[WRITE]); bio_associate_current(bio); @@ -1565,6 +1594,7 @@ int blk_throtl_init(struct request_queue *q) q->td = td; td->queue = q; + td->limit_valid[LIMIT_MAX] = true; /* activate policy */ ret = blkcg_activate_policy(q, &blkcg_policy_throtl); if (ret) -- cgit v1.2.3