From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757830AbcLOUhN (ORCPT ); Thu, 15 Dec 2016 15:37:13 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:47693 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756286AbcLOUdL (ORCPT ); Thu, 15 Dec 2016 15:33:11 -0500 Smtp-Origin-Hostprefix: devbig From: Shaohua Li Smtp-Origin-Hostname: devbig638.prn2.facebook.com To: , CC: , , , Smtp-Origin-Cluster: prn2c22 Subject: [PATCH V5 03/17] blk-throttle: add .low interface Date: Thu, 15 Dec 2016 12:32:54 -0800 Message-ID: X-Mailer: git-send-email 2.9.3 In-Reply-To: References: X-FB-Internal: Safe MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-12-15_14:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add low limit for cgroup and corresponding cgroup interface. Signed-off-by: Shaohua Li --- block/blk-throttle.c | 134 ++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 106 insertions(+), 28 deletions(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index a75bfa2..fcc4199 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -84,6 +84,7 @@ enum tg_state_flags { #define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node) enum { + LIMIT_LOW, LIMIT_MAX, LIMIT_CNT, }; @@ -124,11 +125,15 @@ struct throtl_grp { /* are there any throtl rules between this group and td? */ bool has_rules[2]; - /* bytes per second rate limits */ + /* internally used bytes per second rate limits */ uint64_t bps[2][LIMIT_CNT]; + /* user configured bps limits */ + uint64_t bps_conf[2][LIMIT_CNT]; - /* IOPS limits */ + /* internally used IOPS limits */ unsigned int iops[2][LIMIT_CNT]; + /* user configured IOPS limits */ + unsigned int iops_conf[2][LIMIT_CNT]; /* Number of bytes disptached in current slice */ uint64_t bytes_disp[2]; @@ -355,6 +360,8 @@ static struct blkg_policy_data *throtl_pd_alloc(gfp_t gfp, int node) for (index = 0; index < LIMIT_CNT; index++) { tg->bps[rw][index] = U64_MAX; tg->iops[rw][index] = UINT_MAX; + tg->bps_conf[rw][index] = U64_MAX; + tg->iops_conf[rw][index] = UINT_MAX; } } @@ -414,6 +421,46 @@ static void throtl_pd_online(struct blkg_policy_data *pd) tg_update_has_rules(pd_to_tg(pd)); } +static void blk_throtl_update_valid_limit(struct throtl_data *td) +{ + struct cgroup_subsys_state *pos_css; + struct blkcg_gq *blkg; + bool low_valid = false; + + rcu_read_lock(); + blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) { + struct throtl_grp *tg = blkg_to_tg(blkg); + + if (tg->bps[READ][LIMIT_LOW] != U64_MAX || + tg->bps[WRITE][LIMIT_LOW] != U64_MAX || + tg->iops[READ][LIMIT_LOW] != UINT_MAX || + tg->iops[WRITE][LIMIT_LOW] != UINT_MAX) + low_valid = true; + } + rcu_read_unlock(); + + if (low_valid) + td->limit_valid[LIMIT_LOW] = true; + else + td->limit_valid[LIMIT_LOW] = false; +} + +static void throtl_pd_offline(struct blkg_policy_data *pd) +{ + struct throtl_grp *tg = pd_to_tg(pd); + + tg->bps[READ][LIMIT_LOW] = U64_MAX; + tg->bps[WRITE][LIMIT_LOW] = U64_MAX; + tg->iops[READ][LIMIT_LOW] = UINT_MAX; + tg->iops[WRITE][LIMIT_LOW] = UINT_MAX; + + blk_throtl_update_valid_limit(tg->td); + + if (tg->td->limit_index == LIMIT_LOW && + !tg->td->limit_valid[LIMIT_LOW]) + tg->td->limit_index = LIMIT_MAX; +} + static void throtl_pd_free(struct blkg_policy_data *pd) { struct throtl_grp *tg = pd_to_tg(pd); @@ -1284,7 +1331,7 @@ static struct cftype throtl_legacy_files[] = { { } /* terminate */ }; -static u64 tg_prfill_max(struct seq_file *sf, struct blkg_policy_data *pd, +static u64 tg_prfill_limit(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct throtl_grp *tg = pd_to_tg(pd); @@ -1294,38 +1341,38 @@ static u64 tg_prfill_max(struct seq_file *sf, struct blkg_policy_data *pd, if (!dname) return 0; - 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) + if (tg->bps_conf[READ][off] == U64_MAX && + tg->bps_conf[WRITE][off] == U64_MAX && + tg->iops_conf[READ][off] == UINT_MAX && + tg->iops_conf[WRITE][off] == UINT_MAX) return 0; - if (tg->bps[READ][LIMIT_MAX] != U64_MAX) + if (tg->bps_conf[READ][off] != U64_MAX) snprintf(bufs[0], sizeof(bufs[0]), "%llu", - tg->bps[READ][LIMIT_MAX]); - if (tg->bps[WRITE][LIMIT_MAX] != U64_MAX) + tg->bps_conf[READ][off]); + if (tg->bps_conf[WRITE][off] != U64_MAX) snprintf(bufs[1], sizeof(bufs[1]), "%llu", - tg->bps[WRITE][LIMIT_MAX]); - if (tg->iops[READ][LIMIT_MAX] != UINT_MAX) + tg->bps_conf[WRITE][off]); + if (tg->iops_conf[READ][off] != UINT_MAX) snprintf(bufs[2], sizeof(bufs[2]), "%u", - tg->iops[READ][LIMIT_MAX]); - if (tg->iops[WRITE][LIMIT_MAX] != UINT_MAX) + tg->iops_conf[READ][off]); + if (tg->iops_conf[WRITE][off] != UINT_MAX) snprintf(bufs[3], sizeof(bufs[3]), "%u", - tg->iops[WRITE][LIMIT_MAX]); + tg->iops_conf[WRITE][off]); seq_printf(sf, "%s rbps=%s wbps=%s riops=%s wiops=%s\n", dname, bufs[0], bufs[1], bufs[2], bufs[3]); return 0; } -static int tg_print_max(struct seq_file *sf, void *v) +static int tg_print_limit(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_max, + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_limit, &blkcg_policy_throtl, seq_cft(sf)->private, false); return 0; } -static ssize_t tg_set_max(struct kernfs_open_file *of, +static ssize_t tg_set_limit(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { struct blkcg *blkcg = css_to_blkcg(of_css(of)); @@ -1333,6 +1380,7 @@ static ssize_t tg_set_max(struct kernfs_open_file *of, struct throtl_grp *tg; u64 v[4]; int ret; + int index = of_cft(of)->private; ret = blkg_conf_prep(blkcg, &blkcg_policy_throtl, buf, &ctx); if (ret) @@ -1340,10 +1388,10 @@ static ssize_t tg_set_max(struct kernfs_open_file *of, tg = blkg_to_tg(ctx.blkg); - 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]; + v[0] = tg->bps_conf[READ][index]; + v[1] = tg->bps_conf[WRITE][index]; + v[2] = tg->iops_conf[READ][index]; + v[3] = tg->iops_conf[WRITE][index]; while (true) { char tok[27]; /* wiops=18446744073709551616 */ @@ -1380,11 +1428,31 @@ static ssize_t tg_set_max(struct kernfs_open_file *of, goto out_finish; } - 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->bps_conf[READ][index] = v[0]; + tg->bps_conf[WRITE][index] = v[1]; + tg->iops_conf[READ][index] = v[2]; + tg->iops_conf[WRITE][index] = v[3]; + if (index == LIMIT_MAX) { + tg->bps[READ][index] = v[0]; + tg->bps[WRITE][index] = v[1]; + tg->iops[READ][index] = v[2]; + tg->iops[WRITE][index] = v[3]; + } + tg->bps[READ][LIMIT_LOW] = min(tg->bps_conf[READ][LIMIT_LOW], + tg->bps_conf[READ][LIMIT_MAX]); + tg->bps[WRITE][LIMIT_LOW] = min(tg->bps_conf[WRITE][LIMIT_LOW], + tg->bps_conf[WRITE][LIMIT_MAX]); + tg->iops[READ][LIMIT_LOW] = min(tg->iops_conf[READ][LIMIT_LOW], + tg->iops_conf[READ][LIMIT_MAX]); + tg->iops[WRITE][LIMIT_LOW] = min(tg->iops_conf[WRITE][LIMIT_LOW], + tg->iops_conf[WRITE][LIMIT_MAX]); + + if (index == LIMIT_LOW) { + blk_throtl_update_valid_limit(tg->td); + if (tg->td->limit_valid[LIMIT_LOW]) + tg->td->limit_index = LIMIT_LOW; + } tg_conf_updated(tg); ret = 0; out_finish: @@ -1394,10 +1462,18 @@ static ssize_t tg_set_max(struct kernfs_open_file *of, static struct cftype throtl_files[] = { { + .name = "low", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = tg_print_limit, + .write = tg_set_limit, + .private = LIMIT_LOW, + }, + { .name = "max", .flags = CFTYPE_NOT_ON_ROOT, - .seq_show = tg_print_max, - .write = tg_set_max, + .seq_show = tg_print_limit, + .write = tg_set_limit, + .private = LIMIT_MAX, }, { } /* terminate */ }; @@ -1416,6 +1492,7 @@ static struct blkcg_policy blkcg_policy_throtl = { .pd_alloc_fn = throtl_pd_alloc, .pd_init_fn = throtl_pd_init, .pd_online_fn = throtl_pd_online, + .pd_offline_fn = throtl_pd_offline, .pd_free_fn = throtl_pd_free, }; @@ -1595,6 +1672,7 @@ int blk_throtl_init(struct request_queue *q) td->queue = q; td->limit_valid[LIMIT_MAX] = true; + td->limit_index = LIMIT_MAX; /* activate policy */ ret = blkcg_activate_policy(q, &blkcg_policy_throtl); if (ret) -- 2.9.3