bfq: Add per-device weight
This adds to BFQ the missing per-device weight interfaces:
blkio.bfq.weight_device on legacy and io.bfq.weight on unified. The
implementation pretty closely resembles what we had in CFQ and the parsing code
is basically reused.
Tests
=====
Using two cgroups and three block devices, having weights setup as:
Cgroup test1 test2
============================================
default 100 500
sda 500 100
sdb default default
sdc 200 200
cgroup v1 runs
--------------
sda.test1.out: READ: bw=913MiB/s
sda.test2.out: READ: bw=183MiB/s
sdb.test1.out: READ: bw=213MiB/s
sdb.test2.out: READ: bw=1054MiB/s
sdc.test1.out: READ: bw=650MiB/s
sdc.test2.out: READ: bw=650MiB/s
cgroup v2 runs
--------------
sda.test1.out: READ: bw=915MiB/s
sda.test2.out: READ: bw=184MiB/s
sdb.test1.out: READ: bw=216MiB/s
sdb.test2.out: READ: bw=1069MiB/s
sdc.test1.out: READ: bw=621MiB/s
sdc.test2.out: READ: bw=622MiB/s
Signed-off-by: Fam Zheng <zhengfeiran@bytedance.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Fam Zheng
Jens Axboe
parent
5ff047e328
commit
795fe54c2a
|
|
@ -905,7 +905,7 @@ void bfq_end_wr_async(struct bfq_data *bfqd)
|
|||
bfq_end_wr_async_queues(bfqd, bfqd->root_group);
|
||||
}
|
||||
|
||||
static int bfq_io_show_weight(struct seq_file *sf, void *v)
|
||||
static int bfq_io_show_weight_legacy(struct seq_file *sf, void *v)
|
||||
{
|
||||
struct blkcg *blkcg = css_to_blkcg(seq_css(sf));
|
||||
struct bfq_group_data *bfqgd = blkcg_to_bfqgd(blkcg);
|
||||
|
|
@ -919,8 +919,32 @@ static int bfq_io_show_weight(struct seq_file *sf, void *v)
|
|||
return 0;
|
||||
}
|
||||
|
||||
static void bfq_group_set_weight(struct bfq_group *bfqg, u64 weight)
|
||||
static u64 bfqg_prfill_weight_device(struct seq_file *sf,
|
||||
struct blkg_policy_data *pd, int off)
|
||||
{
|
||||
struct bfq_group *bfqg = pd_to_bfqg(pd);
|
||||
|
||||
if (!bfqg->entity.dev_weight)
|
||||
return 0;
|
||||
return __blkg_prfill_u64(sf, pd, bfqg->entity.dev_weight);
|
||||
}
|
||||
|
||||
static int bfq_io_show_weight(struct seq_file *sf, void *v)
|
||||
{
|
||||
struct blkcg *blkcg = css_to_blkcg(seq_css(sf));
|
||||
struct bfq_group_data *bfqgd = blkcg_to_bfqgd(blkcg);
|
||||
|
||||
seq_printf(sf, "default %u\n", bfqgd->weight);
|
||||
blkcg_print_blkgs(sf, blkcg, bfqg_prfill_weight_device,
|
||||
&blkcg_policy_bfq, 0, false);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void bfq_group_set_weight(struct bfq_group *bfqg, u64 weight, u64 dev_weight)
|
||||
{
|
||||
weight = dev_weight ?: weight;
|
||||
|
||||
bfqg->entity.dev_weight = dev_weight;
|
||||
/*
|
||||
* Setting the prio_changed flag of the entity
|
||||
* to 1 with new_weight == weight would re-set
|
||||
|
|
@ -968,28 +992,71 @@ static int bfq_io_set_weight_legacy(struct cgroup_subsys_state *css,
|
|||
struct bfq_group *bfqg = blkg_to_bfqg(blkg);
|
||||
|
||||
if (bfqg)
|
||||
bfq_group_set_weight(bfqg, val);
|
||||
bfq_group_set_weight(bfqg, val, 0);
|
||||
}
|
||||
spin_unlock_irq(&blkcg->lock);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static ssize_t bfq_io_set_device_weight(struct kernfs_open_file *of,
|
||||
char *buf, size_t nbytes,
|
||||
loff_t off)
|
||||
{
|
||||
int ret;
|
||||
struct blkg_conf_ctx ctx;
|
||||
struct blkcg *blkcg = css_to_blkcg(of_css(of));
|
||||
struct bfq_group *bfqg;
|
||||
u64 v;
|
||||
|
||||
ret = blkg_conf_prep(blkcg, &blkcg_policy_bfq, buf, &ctx);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (sscanf(ctx.body, "%llu", &v) == 1) {
|
||||
/* require "default" on dfl */
|
||||
ret = -ERANGE;
|
||||
if (!v)
|
||||
goto out;
|
||||
} else if (!strcmp(strim(ctx.body), "default")) {
|
||||
v = 0;
|
||||
} else {
|
||||
ret = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
|
||||
bfqg = blkg_to_bfqg(ctx.blkg);
|
||||
|
||||
ret = -ERANGE;
|
||||
if (!v || (v >= BFQ_MIN_WEIGHT && v <= BFQ_MAX_WEIGHT)) {
|
||||
bfq_group_set_weight(bfqg, bfqg->entity.weight, v);
|
||||
ret = 0;
|
||||
}
|
||||
out:
|
||||
blkg_conf_finish(&ctx);
|
||||
return ret ?: nbytes;
|
||||
}
|
||||
|
||||
static ssize_t bfq_io_set_weight(struct kernfs_open_file *of,
|
||||
char *buf, size_t nbytes,
|
||||
loff_t off)
|
||||
{
|
||||
u64 weight;
|
||||
/* First unsigned long found in the file is used */
|
||||
int ret = kstrtoull(strim(buf), 0, &weight);
|
||||
char *endp;
|
||||
int ret;
|
||||
u64 v;
|
||||
|
||||
if (ret)
|
||||
return ret;
|
||||
buf = strim(buf);
|
||||
|
||||
ret = bfq_io_set_weight_legacy(of_css(of), NULL, weight);
|
||||
/* "WEIGHT" or "default WEIGHT" sets the default weight */
|
||||
v = simple_strtoull(buf, &endp, 0);
|
||||
if (*endp == '\0' || sscanf(buf, "default %llu", &v) == 1) {
|
||||
ret = bfq_io_set_weight_legacy(of_css(of), NULL, v);
|
||||
return ret ?: nbytes;
|
||||
}
|
||||
|
||||
return bfq_io_set_device_weight(of, buf, nbytes, off);
|
||||
}
|
||||
|
||||
#ifdef CONFIG_BFQ_CGROUP_DEBUG
|
||||
static int bfqg_print_stat(struct seq_file *sf, void *v)
|
||||
{
|
||||
|
|
@ -1146,9 +1213,15 @@ struct cftype bfq_blkcg_legacy_files[] = {
|
|||
{
|
||||
.name = "bfq.weight",
|
||||
.flags = CFTYPE_NOT_ON_ROOT,
|
||||
.seq_show = bfq_io_show_weight,
|
||||
.seq_show = bfq_io_show_weight_legacy,
|
||||
.write_u64 = bfq_io_set_weight_legacy,
|
||||
},
|
||||
{
|
||||
.name = "bfq.weight_device",
|
||||
.flags = CFTYPE_NOT_ON_ROOT,
|
||||
.seq_show = bfq_io_show_weight,
|
||||
.write = bfq_io_set_weight,
|
||||
},
|
||||
|
||||
/* statistics, covers only the tasks in the bfqg */
|
||||
{
|
||||
|
|
|
|||
|
|
@ -168,6 +168,9 @@ struct bfq_entity {
|
|||
/* budget, used also to calculate F_i: F_i = S_i + @budget / @weight */
|
||||
int budget;
|
||||
|
||||
/* device weight, if non-zero, it overrides the default weight of
|
||||
* bfq_group_data */
|
||||
int dev_weight;
|
||||
/* weight of the queue */
|
||||
int weight;
|
||||
/* next weight if a change is in progress */
|
||||
|
|
|
|||
Loading…
Reference in New Issue