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 <s...@fb.com>
---
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 974ec9d..88c0d1e 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;
}
/*
@@ -1447,6 +1446,7 @@ 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;
@@ -1462,7 +1462,9 @@ 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)
@@ -1477,9 +1479,16 @@ 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;
}
@@ -1497,6 +1506,7 @@ 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;
@@ -1511,6 +1521,7 @@ 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;
@@ -1542,6 +1553,8 @@ 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;
}
@@ -1570,6 +1583,8 @@ 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;
@@ -2114,10 +2129,13 @@ 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;
+ }
/*
* some tg are created before queue is fully initialized, eg, nonrot
@@ -2127,10 +2145,7 @@ 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();
}
--
2.9.3
--
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