From: Shaohua Li <shli@fb.com>
To: <linux-kernel@vger.kernel.org>, <linux-block@vger.kernel.org>
Cc: <axboe@kernel.dk>, <tj@kernel.org>,
Vivek Goyal <vgoyal@redhat.com>, <jmoyer@redhat.com>,
<Kernel-team@fb.com>
Subject: [PATCH V7 04/18] blk-throttle: add .low interface
Date: Mon, 27 Mar 2017 10:51:32 -0700 [thread overview]
Message-ID: <a801410f808acfe754992c62edb08dbc96ded231.1490634565.git.shli@fb.com> (raw)
In-Reply-To: <cover.1490634565.git.shli@fb.com>
Add low limit for cgroup and corresponding cgroup interface. To be
consistent with memcg, we allow users configure .low limit higher than
.max limit. But the internal logic always assumes .low limit is lower
than .max limit. So we add extra bps/iops_conf fields in throtl_grp for
userspace configuration. Old bps/iops fields in throtl_grp will be the
actual limit we use for throttling.
Signed-off-by: Shaohua Li <shli@fb.com>
---
block/blk-throttle.c | 144 +++++++++++++++++++++++++++++++++++++++++----------
1 file changed, 116 insertions(+), 28 deletions(-)
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 1da9f30..b7b69ec 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 +360,11 @@ static struct blkg_policy_data *throtl_pd_alloc(gfp_t gfp, int node)
tg->bps[WRITE][LIMIT_MAX] = U64_MAX;
tg->iops[READ][LIMIT_MAX] = UINT_MAX;
tg->iops[WRITE][LIMIT_MAX] = UINT_MAX;
+ tg->bps_conf[READ][LIMIT_MAX] = U64_MAX;
+ tg->bps_conf[WRITE][LIMIT_MAX] = U64_MAX;
+ tg->iops_conf[READ][LIMIT_MAX] = UINT_MAX;
+ tg->iops_conf[WRITE][LIMIT_MAX] = UINT_MAX;
+ /* LIMIT_LOW will have default value 0 */
return &tg->pd;
}
@@ -412,6 +422,41 @@ static void throtl_pd_online(struct blkg_policy_data *pd)
tg_update_has_rules(pd_to_tg(pd));
}
+static void blk_throtl_update_limit_valid(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] || tg->bps[WRITE][LIMIT_LOW] ||
+ tg->iops[READ][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW])
+ low_valid = true;
+ }
+ rcu_read_unlock();
+
+ td->limit_valid[LIMIT_LOW] = low_valid;
+}
+
+static void throtl_pd_offline(struct blkg_policy_data *pd)
+{
+ struct throtl_grp *tg = pd_to_tg(pd);
+
+ tg->bps[READ][LIMIT_LOW] = 0;
+ tg->bps[WRITE][LIMIT_LOW] = 0;
+ tg->iops[READ][LIMIT_LOW] = 0;
+ tg->iops[WRITE][LIMIT_LOW] = 0;
+
+ blk_throtl_update_limit_valid(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);
@@ -1284,48 +1329,58 @@ 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);
const char *dname = blkg_dev_name(pd->blkg);
char bufs[4][21] = { "max", "max", "max", "max" };
+ u64 bps_dft;
+ unsigned int iops_dft;
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 (off == LIMIT_LOW) {
+ bps_dft = 0;
+ iops_dft = 0;
+ } else {
+ bps_dft = U64_MAX;
+ iops_dft = UINT_MAX;
+ }
+
+ 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)
return 0;
- if (tg->bps[READ][LIMIT_MAX] != U64_MAX)
+ if (tg->bps_conf[READ][off] != bps_dft)
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] != bps_dft)
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] != iops_dft)
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] != iops_dft)
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 +1388,7 @@ 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 +1396,10 @@ 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 +1436,31 @@ 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_limit_valid(tg->td);
+ if (tg->td->limit_valid[LIMIT_LOW])
+ tg->td->limit_index = LIMIT_LOW;
+ }
tg_conf_updated(tg);
ret = 0;
out_finish:
@@ -1393,11 +1469,21 @@ static ssize_t tg_set_max(struct kernfs_open_file *of,
}
static struct cftype throtl_files[] = {
+#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
+ {
+ .name = "low",
+ .flags = CFTYPE_NOT_ON_ROOT,
+ .seq_show = tg_print_limit,
+ .write = tg_set_limit,
+ .private = LIMIT_LOW,
+ },
+#endif
{
.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 +1502,7 @@ 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 +1682,7 @@ 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
next prev parent reply other threads:[~2017-03-27 18:38 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-27 17:51 [PATCH V7 00/18] blk-throttle: add .low limit Shaohua Li
2017-03-27 17:51 ` [PATCH V7 01/18] blk-throttle: use U64_MAX/UINT_MAX to replace -1 Shaohua Li
2017-03-27 17:51 ` [PATCH V7 02/18] blk-throttle: prepare support multiple limits Shaohua Li
2017-03-27 17:51 ` [PATCH V7 03/18] blk-throttle: add configure option for new .low interface Shaohua Li
2017-03-27 17:51 ` Shaohua Li [this message]
2017-03-27 17:51 ` [PATCH V7 05/18] blk-throttle: configure bps/iops limit for cgroup in low limit Shaohua Li
2017-03-27 17:51 ` [PATCH V7 06/18] blk-throttle: add upgrade logic for LIMIT_LOW state Shaohua Li
2017-03-27 17:51 ` [PATCH V7 07/18] blk-throttle: add downgrade logic Shaohua Li
2017-03-27 17:51 ` [PATCH V7 08/18] blk-throttle: make sure expire time isn't too big Shaohua Li
2017-03-27 17:51 ` [PATCH V7 09/18] blk-throttle: make throtl_slice tunable Shaohua Li
2017-03-27 17:51 ` [PATCH V7 10/18] blk-throttle: choose a small throtl_slice for SSD Shaohua Li
2017-03-27 17:51 ` [PATCH V7 11/18] blk-throttle: detect completed idle cgroup Shaohua Li
2017-03-27 17:51 ` [PATCH V7 12/18] blk-throttle: make bandwidth change smooth Shaohua Li
2017-03-27 17:51 ` [PATCH V7 13/18] blk-throttle: add a simple idle detection Shaohua Li
2017-03-27 17:51 ` [PATCH V7 14/18] blk-throttle: add interface to configure idle time threshold Shaohua Li
2017-03-27 17:51 ` [PATCH V7 15/18] blk-throttle: ignore idle cgroup limit Shaohua Li
2017-03-27 17:51 ` [PATCH V7 16/18] blk-throttle: add interface for per-cgroup target latency Shaohua Li
2017-03-27 17:51 ` [PATCH V7 17/18] blk-throttle: add a mechanism to estimate IO latency Shaohua Li
2017-03-27 17:51 ` [PATCH V7 18/18] blk-throttle: add latency target support Shaohua Li
2017-03-27 18:15 ` [PATCH V7 00/18] blk-throttle: add .low limit Jens Axboe
2017-03-27 19:00 ` Shaohua Li
2017-03-27 19:11 ` Jens Axboe
2017-03-27 22:19 ` [PATCH 0/3] blk-throttle: add .low limit fix Shaohua Li
2017-03-27 22:19 ` [PATCH 1/3] block: track request size in blk_issue_stat Shaohua Li
2017-03-27 22:19 ` [PATCH 2/3] blk-throttle: add a mechanism to estimate IO latency Shaohua Li
2017-03-27 22:19 ` [PATCH 3/3] blk-throttle: add latency target support Shaohua Li
2017-03-28 15:58 ` [PATCH 0/3] blk-throttle: add .low limit fix Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=a801410f808acfe754992c62edb08dbc96ded231.1490634565.git.shli@fb.com \
--to=shli@fb.com \
--cc=Kernel-team@fb.com \
--cc=axboe@kernel.dk \
--cc=jmoyer@redhat.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tj@kernel.org \
--cc=vgoyal@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®