From ada75b6e5b2a939401d4919dfaf2f2fc9484f68a Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Mon, 27 Mar 2017 10:51:42 -0700 Subject: [PATCH] blk-throttle: add interface to configure idle time threshold Add interface to configure the threshold. The io.low interface will like: echo "8:16 rbps=2097152 wbps=max idle=2000" > io.low idle is in microsecond unit. Signed-off-by: Shaohua Li Signed-off-by: Jens Axboe --- block/blk-throttle.c | 41 ++++++++++++++++++++++++++++------------- 1 file changed, 28 insertions(+), 13 deletions(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 6300f3e..f03e158 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -181,6 +181,8 @@ struct throtl_data unsigned int limit_index; bool limit_valid[LIMIT_CNT]; + unsigned long dft_idletime_threshold; /* us */ + unsigned long low_upgrade_time; unsigned long low_downgrade_time; @@ -477,10 +479,7 @@ static void throtl_pd_init(struct blkg_policy_data *pd) sq->parent_sq = &blkg_to_tg(blkg->parent)->service_queue; tg->td = td; - if (blk_queue_nonrot(td->queue)) - tg->idletime_threshold = DFL_IDLE_THRESHOLD_SSD; - else - tg->idletime_threshold = DFL_IDLE_THRESHOLD_HD; + tg->idletime_threshold = td->dft_idletime_threshold; } /* @@ -1449,6 +1448,7 @@ static u64 tg_prfill_limit(struct seq_file *sf, struct blkg_policy_data *pd, char bufs[4][21] = { "max", "max", "max", "max" }; u64 bps_dft; unsigned int iops_dft; + char idle_time[26] = ""; if (!dname) return 0; @@ -1464,7 +1464,9 @@ static u64 tg_prfill_limit(struct seq_file *sf, struct blkg_policy_data *pd, if (tg->bps_conf[READ][off] == bps_dft && tg->bps_conf[WRITE][off] == bps_dft && tg->iops_conf[READ][off] == iops_dft && - tg->iops_conf[WRITE][off] == iops_dft) + tg->iops_conf[WRITE][off] == iops_dft && + (off != LIMIT_LOW || tg->idletime_threshold == + tg->td->dft_idletime_threshold)) return 0; if (tg->bps_conf[READ][off] != bps_dft) @@ -1479,9 +1481,16 @@ static u64 tg_prfill_limit(struct seq_file *sf, struct blkg_policy_data *pd, if (tg->iops_conf[WRITE][off] != iops_dft) snprintf(bufs[3], sizeof(bufs[3]), "%u", tg->iops_conf[WRITE][off]); + if (off == LIMIT_LOW) { + if (tg->idletime_threshold == ULONG_MAX) + strcpy(idle_time, " idle=max"); + else + snprintf(idle_time, sizeof(idle_time), " idle=%lu", + tg->idletime_threshold); + } - seq_printf(sf, "%s rbps=%s wbps=%s riops=%s wiops=%s\n", - dname, bufs[0], bufs[1], bufs[2], bufs[3]); + seq_printf(sf, "%s rbps=%s wbps=%s riops=%s wiops=%s%s\n", + dname, bufs[0], bufs[1], bufs[2], bufs[3], idle_time); return 0; } @@ -1499,6 +1508,7 @@ static ssize_t tg_set_limit(struct kernfs_open_file *of, struct blkg_conf_ctx ctx; struct throtl_grp *tg; u64 v[4]; + unsigned long idle_time; int ret; int index = of_cft(of)->private; @@ -1513,6 +1523,7 @@ static ssize_t tg_set_limit(struct kernfs_open_file *of, v[2] = tg->iops_conf[READ][index]; v[3] = tg->iops_conf[WRITE][index]; + idle_time = tg->idletime_threshold; while (true) { char tok[27]; /* wiops=18446744073709551616 */ char *p; @@ -1544,6 +1555,8 @@ static ssize_t tg_set_limit(struct kernfs_open_file *of, v[2] = min_t(u64, val, UINT_MAX); else if (!strcmp(tok, "wiops")) v[3] = min_t(u64, val, UINT_MAX); + else if (off == LIMIT_LOW && !strcmp(tok, "idle")) + idle_time = val; else goto out_finish; } @@ -1572,6 +1585,8 @@ static ssize_t tg_set_limit(struct kernfs_open_file *of, blk_throtl_update_limit_valid(tg->td); if (tg->td->limit_valid[LIMIT_LOW]) tg->td->limit_index = LIMIT_LOW; + tg->idletime_threshold = (idle_time == ULONG_MAX) ? + ULONG_MAX : idle_time; } tg_conf_updated(tg); ret = 0; @@ -2122,10 +2137,13 @@ void blk_throtl_register_queue(struct request_queue *q) td = q->td; BUG_ON(!td); - if (blk_queue_nonrot(q)) + if (blk_queue_nonrot(q)) { td->throtl_slice = DFL_THROTL_SLICE_SSD; - else + td->dft_idletime_threshold = DFL_IDLE_THRESHOLD_SSD; + } else { td->throtl_slice = DFL_THROTL_SLICE_HD; + td->dft_idletime_threshold = DFL_IDLE_THRESHOLD_HD; + } #ifndef CONFIG_BLK_DEV_THROTTLING_LOW /* if no low limit, use previous default */ td->throtl_slice = DFL_THROTL_SLICE_HD; @@ -2139,10 +2157,7 @@ void blk_throtl_register_queue(struct request_queue *q) blkg_for_each_descendant_post(blkg, pos_css, q->root_blkg) { struct throtl_grp *tg = blkg_to_tg(blkg); - if (blk_queue_nonrot(q)) - tg->idletime_threshold = DFL_IDLE_THRESHOLD_SSD; - else - tg->idletime_threshold = DFL_IDLE_THRESHOLD_HD; + tg->idletime_threshold = td->dft_idletime_threshold; } rcu_read_unlock(); } -- 2.7.4