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-rw-r--r--block/cfq-iosched.c65
1 files changed, 45 insertions, 20 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 019f28eea9df..84887e2eb210 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -82,6 +82,7 @@ struct cfq_rb_root {
unsigned count;
u64 min_vdisktime;
struct rb_node *active;
+ unsigned total_weight;
};
#define CFQ_RB_ROOT (struct cfq_rb_root) { RB_ROOT, NULL, 0, 0, }
@@ -172,6 +173,8 @@ struct cfq_group {
/* number of cfqq currently on this group */
int nr_cfqq;
+ /* Per group busy queus average. Useful for workload slice calc. */
+ unsigned int busy_queues_avg[2];
/*
* rr lists of queues with requests, onle rr for each priority class.
* Counts are embedded in the cfq_rb_root
@@ -188,6 +191,8 @@ struct cfq_data {
/* Root service tree for cfq_groups */
struct cfq_rb_root grp_service_tree;
struct cfq_group root_group;
+ /* Number of active cfq groups on group service tree */
+ int nr_groups;
/*
* The priority currently being served
@@ -206,7 +211,6 @@ struct cfq_data {
struct rb_root prio_trees[CFQ_PRIO_LISTS];
unsigned int busy_queues;
- unsigned int busy_queues_avg[2];
int rq_in_driver[2];
int sync_flight;
@@ -354,10 +358,10 @@ static enum wl_type_t cfqq_type(struct cfq_queue *cfqq)
return SYNC_WORKLOAD;
}
-static inline int cfq_busy_queues_wl(enum wl_prio_t wl, struct cfq_data *cfqd)
+static inline int cfq_group_busy_queues_wl(enum wl_prio_t wl,
+ struct cfq_data *cfqd,
+ struct cfq_group *cfqg)
{
- struct cfq_group *cfqg = &cfqd->root_group;
-
if (wl == IDLE_WORKLOAD)
return cfqg->service_tree_idle.count;
@@ -489,18 +493,27 @@ static void update_min_vdisktime(struct cfq_rb_root *st)
* to quickly follows sudden increases and decrease slowly
*/
-static inline unsigned cfq_get_avg_queues(struct cfq_data *cfqd, bool rt)
+static inline unsigned cfq_group_get_avg_queues(struct cfq_data *cfqd,
+ struct cfq_group *cfqg, bool rt)
{
unsigned min_q, max_q;
unsigned mult = cfq_hist_divisor - 1;
unsigned round = cfq_hist_divisor / 2;
- unsigned busy = cfq_busy_queues_wl(rt, cfqd);
+ unsigned busy = cfq_group_busy_queues_wl(rt, cfqd, cfqg);
- min_q = min(cfqd->busy_queues_avg[rt], busy);
- max_q = max(cfqd->busy_queues_avg[rt], busy);
- cfqd->busy_queues_avg[rt] = (mult * max_q + min_q + round) /
+ min_q = min(cfqg->busy_queues_avg[rt], busy);
+ max_q = max(cfqg->busy_queues_avg[rt], busy);
+ cfqg->busy_queues_avg[rt] = (mult * max_q + min_q + round) /
cfq_hist_divisor;
- return cfqd->busy_queues_avg[rt];
+ return cfqg->busy_queues_avg[rt];
+}
+
+static inline unsigned
+cfq_group_slice(struct cfq_data *cfqd, struct cfq_group *cfqg)
+{
+ struct cfq_rb_root *st = &cfqd->grp_service_tree;
+
+ return cfq_target_latency * cfqg->weight / st->total_weight;
}
static inline void
@@ -508,12 +521,17 @@ cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
unsigned slice = cfq_prio_to_slice(cfqd, cfqq);
if (cfqd->cfq_latency) {
- /* interested queues (we consider only the ones with the same
- * priority class) */
- unsigned iq = cfq_get_avg_queues(cfqd, cfq_class_rt(cfqq));
+ /*
+ * interested queues (we consider only the ones with the same
+ * priority class in the cfq group)
+ */
+ unsigned iq = cfq_group_get_avg_queues(cfqd, cfqq->cfqg,
+ cfq_class_rt(cfqq));
unsigned sync_slice = cfqd->cfq_slice[1];
unsigned expect_latency = sync_slice * iq;
- if (expect_latency > cfq_target_latency) {
+ unsigned group_slice = cfq_group_slice(cfqd, cfqq->cfqg);
+
+ if (expect_latency > group_slice) {
unsigned base_low_slice = 2 * cfqd->cfq_slice_idle;
/* scale low_slice according to IO priority
* and sync vs async */
@@ -521,7 +539,7 @@ cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq)
min(slice, base_low_slice * slice / sync_slice);
/* the adapted slice value is scaled to fit all iqs
* into the target latency */
- slice = max(slice * cfq_target_latency / expect_latency,
+ slice = max(slice * group_slice / expect_latency,
low_slice);
}
}
@@ -776,6 +794,8 @@ cfq_group_service_tree_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
__cfq_group_service_tree_add(st, cfqg);
cfqg->on_st = true;
+ cfqd->nr_groups++;
+ st->total_weight += cfqg->weight;
}
static void
@@ -794,6 +814,8 @@ cfq_group_service_tree_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
return;
cfqg->on_st = false;
+ cfqd->nr_groups--;
+ st->total_weight -= cfqg->weight;
if (!RB_EMPTY_NODE(&cfqg->rb_node))
cfq_rb_erase(&cfqg->rb_node, st);
}
@@ -1639,6 +1661,7 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
unsigned slice;
unsigned count;
struct cfq_rb_root *st;
+ unsigned group_slice;
if (!cfqg) {
cfqd->serving_prio = IDLE_WORKLOAD;
@@ -1647,9 +1670,9 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
}
/* Choose next priority. RT > BE > IDLE */
- if (cfq_busy_queues_wl(RT_WORKLOAD, cfqd))
+ if (cfq_group_busy_queues_wl(RT_WORKLOAD, cfqd, cfqg))
cfqd->serving_prio = RT_WORKLOAD;
- else if (cfq_busy_queues_wl(BE_WORKLOAD, cfqd))
+ else if (cfq_group_busy_queues_wl(BE_WORKLOAD, cfqd, cfqg))
cfqd->serving_prio = BE_WORKLOAD;
else {
cfqd->serving_prio = IDLE_WORKLOAD;
@@ -1687,9 +1710,11 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
* proportional to the number of queues in that workload, over
* all the queues in the same priority class
*/
- slice = cfq_target_latency * count /
- max_t(unsigned, cfqd->busy_queues_avg[cfqd->serving_prio],
- cfq_busy_queues_wl(cfqd->serving_prio, cfqd));
+ group_slice = cfq_group_slice(cfqd, cfqg);
+
+ slice = group_slice * count /
+ max_t(unsigned, cfqg->busy_queues_avg[cfqd->serving_prio],
+ cfq_group_busy_queues_wl(cfqd->serving_prio, cfqd, cfqg));
if (cfqd->serving_type == ASYNC_WORKLOAD)
/* async workload slice is scaled down according to
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-07 21:00:12 +0000