#define rb_entry_cfqg(node) rb_entry((node), struct cfq_group, rb_node)
/* blkio-related constants */
-#define CFQ_WEIGHT_MIN 10
-#define CFQ_WEIGHT_MAX 1000
-#define CFQ_WEIGHT_DEFAULT 500
+#define CFQ_WEIGHT_LEGACY_MIN 10
+#define CFQ_WEIGHT_LEGACY_DFL 500
+#define CFQ_WEIGHT_LEGACY_MAX 1000
struct cfq_ttime {
unsigned long last_end_request;
}
#ifdef CONFIG_CFQ_GROUP_IOSCHED
+static int __cfq_set_weight(struct cgroup_subsys_state *css, u64 val,
+ bool on_dfl, bool reset_dev, bool is_leaf_weight);
+
static void cfqg_stats_exit(struct cfqg_stats *stats)
{
blkg_rwstat_exit(&stats->merged);
static void cfq_cpd_init(struct blkcg_policy_data *cpd)
{
struct cfq_group_data *cgd = cpd_to_cfqgd(cpd);
+ unsigned int weight = cgroup_on_dfl(blkcg_root.css.cgroup) ?
+ CGROUP_WEIGHT_DFL : CFQ_WEIGHT_LEGACY_DFL;
- if (cpd_to_blkcg(cpd) == &blkcg_root) {
- cgd->weight = 2 * CFQ_WEIGHT_DEFAULT;
- cgd->leaf_weight = 2 * CFQ_WEIGHT_DEFAULT;
- } else {
- cgd->weight = CFQ_WEIGHT_DEFAULT;
- cgd->leaf_weight = CFQ_WEIGHT_DEFAULT;
- }
+ if (cpd_to_blkcg(cpd) == &blkcg_root)
+ weight *= 2;
+
+ cgd->weight = weight;
+ cgd->leaf_weight = weight;
}
static void cfq_cpd_free(struct blkcg_policy_data *cpd)
kfree(cpd_to_cfqgd(cpd));
}
+static void cfq_cpd_bind(struct blkcg_policy_data *cpd)
+{
+ struct blkcg *blkcg = cpd_to_blkcg(cpd);
+ bool on_dfl = cgroup_on_dfl(blkcg_root.css.cgroup);
+ unsigned int weight = on_dfl ? CGROUP_WEIGHT_DFL : CFQ_WEIGHT_LEGACY_DFL;
+
+ if (blkcg == &blkcg_root)
+ weight *= 2;
+
+ WARN_ON_ONCE(__cfq_set_weight(&blkcg->css, weight, on_dfl, true, false));
+ WARN_ON_ONCE(__cfq_set_weight(&blkcg->css, weight, on_dfl, true, true));
+}
+
static struct blkg_policy_data *cfq_pd_alloc(gfp_t gfp, int node)
{
struct cfq_group *cfqg;
static ssize_t __cfqg_set_weight_device(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off,
- bool is_leaf_weight)
+ bool on_dfl, bool is_leaf_weight)
{
+ unsigned int min = on_dfl ? CGROUP_WEIGHT_MIN : CFQ_WEIGHT_LEGACY_MIN;
+ unsigned int max = on_dfl ? CGROUP_WEIGHT_MAX : CFQ_WEIGHT_LEGACY_MAX;
struct blkcg *blkcg = css_to_blkcg(of_css(of));
struct blkg_conf_ctx ctx;
struct cfq_group *cfqg;
if (ret)
return ret;
- ret = -EINVAL;
- if (sscanf(ctx.body, "%llu", &v) != 1)
+ if (sscanf(ctx.body, "%llu", &v) == 1) {
+ /* require "default" on dfl */
+ ret = -ERANGE;
+ if (!v && on_dfl)
+ goto out_finish;
+ } else if (!strcmp(strim(ctx.body), "default")) {
+ v = 0;
+ } else {
+ ret = -EINVAL;
goto out_finish;
+ }
cfqg = blkg_to_cfqg(ctx.blkg);
cfqgd = blkcg_to_cfqgd(blkcg);
ret = -ERANGE;
- if (!v || (v >= CFQ_WEIGHT_MIN && v <= CFQ_WEIGHT_MAX)) {
+ if (!v || (v >= min && v <= max)) {
if (!is_leaf_weight) {
cfqg->dev_weight = v;
cfqg->new_weight = v ?: cfqgd->weight;
static ssize_t cfqg_set_weight_device(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off)
{
- return __cfqg_set_weight_device(of, buf, nbytes, off, false);
+ return __cfqg_set_weight_device(of, buf, nbytes, off, false, false);
}
static ssize_t cfqg_set_leaf_weight_device(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off)
{
- return __cfqg_set_weight_device(of, buf, nbytes, off, true);
+ return __cfqg_set_weight_device(of, buf, nbytes, off, false, true);
}
-static int __cfq_set_weight(struct cgroup_subsys_state *css, struct cftype *cft,
- u64 val, bool is_leaf_weight)
+static int __cfq_set_weight(struct cgroup_subsys_state *css, u64 val,
+ bool on_dfl, bool reset_dev, bool is_leaf_weight)
{
+ unsigned int min = on_dfl ? CGROUP_WEIGHT_MIN : CFQ_WEIGHT_LEGACY_MIN;
+ unsigned int max = on_dfl ? CGROUP_WEIGHT_MAX : CFQ_WEIGHT_LEGACY_MAX;
struct blkcg *blkcg = css_to_blkcg(css);
struct blkcg_gq *blkg;
struct cfq_group_data *cfqgd;
int ret = 0;
- if (val < CFQ_WEIGHT_MIN || val > CFQ_WEIGHT_MAX)
- return -EINVAL;
+ if (val < min || val > max)
+ return -ERANGE;
spin_lock_irq(&blkcg->lock);
cfqgd = blkcg_to_cfqgd(blkcg);
continue;
if (!is_leaf_weight) {
+ if (reset_dev)
+ cfqg->dev_weight = 0;
if (!cfqg->dev_weight)
cfqg->new_weight = cfqgd->weight;
} else {
+ if (reset_dev)
+ cfqg->dev_leaf_weight = 0;
if (!cfqg->dev_leaf_weight)
cfqg->new_leaf_weight = cfqgd->leaf_weight;
}
static int cfq_set_weight(struct cgroup_subsys_state *css, struct cftype *cft,
u64 val)
{
- return __cfq_set_weight(css, cft, val, false);
+ return __cfq_set_weight(css, val, false, false, false);
}
static int cfq_set_leaf_weight(struct cgroup_subsys_state *css,
struct cftype *cft, u64 val)
{
- return __cfq_set_weight(css, cft, val, true);
+ return __cfq_set_weight(css, val, false, false, true);
}
static int cfqg_print_stat(struct seq_file *sf, void *v)
#endif /* CONFIG_DEBUG_BLK_CGROUP */
{ } /* terminate */
};
+
+static int cfq_print_weight_on_dfl(struct seq_file *sf, void *v)
+{
+ struct blkcg *blkcg = css_to_blkcg(seq_css(sf));
+ struct cfq_group_data *cgd = blkcg_to_cfqgd(blkcg);
+
+ seq_printf(sf, "default %u\n", cgd->weight);
+ blkcg_print_blkgs(sf, blkcg, cfqg_prfill_weight_device,
+ &blkcg_policy_cfq, 0, false);
+ return 0;
+}
+
+static ssize_t cfq_set_weight_on_dfl(struct kernfs_open_file *of,
+ char *buf, size_t nbytes, loff_t off)
+{
+ char *endp;
+ int ret;
+ u64 v;
+
+ buf = strim(buf);
+
+ /* "WEIGHT" or "default WEIGHT" sets the default weight */
+ v = simple_strtoull(buf, &endp, 0);
+ if (*endp == '\0' || sscanf(buf, "default %llu", &v) == 1) {
+ ret = __cfq_set_weight(of_css(of), v, true, false, false);
+ return ret ?: nbytes;
+ }
+
+ /* "MAJ:MIN WEIGHT" */
+ return __cfqg_set_weight_device(of, buf, nbytes, off, true, false);
+}
+
+static struct cftype cfq_blkcg_files[] = {
+ {
+ .name = "weight",
+ .flags = CFTYPE_NOT_ON_ROOT,
+ .seq_show = cfq_print_weight_on_dfl,
+ .write = cfq_set_weight_on_dfl,
+ },
+ { } /* terminate */
+};
+
#else /* GROUP_IOSCHED */
static struct cfq_group *cfq_lookup_cfqg(struct cfq_data *cfqd,
struct blkcg *blkcg)
goto out_free;
cfq_init_cfqg_base(cfqd->root_group);
+ cfqd->root_group->weight = 2 * CFQ_WEIGHT_LEGACY_DFL;
+ cfqd->root_group->leaf_weight = 2 * CFQ_WEIGHT_LEGACY_DFL;
#endif
- cfqd->root_group->weight = 2 * CFQ_WEIGHT_DEFAULT;
- cfqd->root_group->leaf_weight = 2 * CFQ_WEIGHT_DEFAULT;
/*
* Not strictly needed (since RB_ROOT just clears the node and we
#ifdef CONFIG_CFQ_GROUP_IOSCHED
static struct blkcg_policy blkcg_policy_cfq = {
+ .dfl_cftypes = cfq_blkcg_files,
.legacy_cftypes = cfq_blkcg_legacy_files,
.cpd_alloc_fn = cfq_cpd_alloc,
.cpd_init_fn = cfq_cpd_init,
.cpd_free_fn = cfq_cpd_free,
+ .cpd_bind_fn = cfq_cpd_bind,
.pd_alloc_fn = cfq_pd_alloc,
.pd_init_fn = cfq_pd_init,