Introduce cfq_entity for CFQ queue
Signed-off-by: Gui Jianfeng <[email protected]>
---
block/cfq-iosched.c | 118 ++++++++++++++++++++++++++++++++------------------
1 files changed, 75 insertions(+), 43 deletions(-)
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index f083bda..939c6a6 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -92,19 +92,29 @@ struct cfq_rb_root {
.count = 0, .min_vdisktime = 0, }
/*
+ * This's the CFQ queue schedule entity which is scheduled on service tree.
+ */
+struct cfq_entity {
+ /* service tree */
+ struct cfq_rb_root *service_tree;
+ /* service_tree member */
+ struct rb_node rb_node;
+ /* service_tree key, represent the position on the tree */
+ unsigned long rb_key;
+};
+
+/*
* Per process-grouping structure
*/
struct cfq_queue {
+ /* The schedule entity */
+ struct cfq_entity cfqe;
/* reference count */
int ref;
/* various state flags, see below */
unsigned int flags;
/* parent cfq_data */
struct cfq_data *cfqd;
- /* service_tree member */
- struct rb_node rb_node;
- /* service_tree key */
- unsigned long rb_key;
/* prio tree member */
struct rb_node p_node;
/* prio tree root we belong to, if any */
@@ -143,7 +153,6 @@ struct cfq_queue {
u32 seek_history;
sector_t last_request_pos;
- struct cfq_rb_root *service_tree;
struct cfq_queue *new_cfqq;
struct cfq_group *cfqg;
struct cfq_group *orig_cfqg;
@@ -302,6 +311,15 @@ struct cfq_data {
struct rcu_head rcu;
};
+static inline struct cfq_queue *
+cfqq_of_entity(struct cfq_entity *cfqe)
+{
+ if (cfqe)
+ return container_of(cfqe, struct cfq_queue, cfqe);
+
+ return NULL;
+}
+
static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd);
static struct cfq_rb_root *service_tree_for(struct cfq_group *cfqg,
@@ -743,7 +761,7 @@ cfq_choose_req(struct cfq_data *cfqd, struct request *rq1, struct request *rq2,
/*
* The below is leftmost cache rbtree addon
*/
-static struct cfq_queue *cfq_rb_first(struct cfq_rb_root *root)
+static struct cfq_entity *cfq_rb_first(struct cfq_rb_root *root)
{
/* Service tree is empty */
if (!root->count)
@@ -753,7 +771,7 @@ static struct cfq_queue *cfq_rb_first(struct cfq_rb_root *root)
root->left = rb_first(&root->rb);
if (root->left)
- return rb_entry(root->left, struct cfq_queue, rb_node);
+ return rb_entry(root->left, struct cfq_entity, rb_node);
return NULL;
}
@@ -1171,21 +1189,24 @@ static inline void cfq_put_cfqg(struct cfq_group *cfqg) {}
static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
bool add_front)
{
+ struct cfq_entity *cfqe;
struct rb_node **p, *parent;
- struct cfq_queue *__cfqq;
+ struct cfq_entity *__cfqe;
unsigned long rb_key;
struct cfq_rb_root *service_tree;
int left;
int new_cfqq = 1;
int group_changed = 0;
+ cfqe = &cfqq->cfqe;
+
#ifdef CONFIG_CFQ_GROUP_IOSCHED
if (!cfqd->cfq_group_isolation
&& cfqq_type(cfqq) == SYNC_NOIDLE_WORKLOAD
&& cfqq->cfqg && cfqq->cfqg != &cfqd->root_group) {
/* Move this cfq to root group */
cfq_log_cfqq(cfqd, cfqq, "moving to root group");
- if (!RB_EMPTY_NODE(&cfqq->rb_node))
+ if (!RB_EMPTY_NODE(&cfqe->rb_node))
cfq_group_service_tree_del(cfqd, cfqq->cfqg);
cfqq->orig_cfqg = cfqq->cfqg;
cfqq->cfqg = &cfqd->root_group;
@@ -1195,7 +1216,7 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
&& cfqq_type(cfqq) == SYNC_WORKLOAD && cfqq->orig_cfqg) {
/* cfqq is sequential now needs to go to its original group */
BUG_ON(cfqq->cfqg != &cfqd->root_group);
- if (!RB_EMPTY_NODE(&cfqq->rb_node))
+ if (!RB_EMPTY_NODE(&cfqe->rb_node))
cfq_group_service_tree_del(cfqd, cfqq->cfqg);
cfq_put_cfqg(cfqq->cfqg);
cfqq->cfqg = cfqq->orig_cfqg;
@@ -1210,9 +1231,9 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
if (cfq_class_idle(cfqq)) {
rb_key = CFQ_IDLE_DELAY;
parent = rb_last(&service_tree->rb);
- if (parent && parent != &cfqq->rb_node) {
- __cfqq = rb_entry(parent, struct cfq_queue, rb_node);
- rb_key += __cfqq->rb_key;
+ if (parent && parent != &cfqe->rb_node) {
+ __cfqe = rb_entry(parent, struct cfq_entity, rb_node);
+ rb_key += __cfqe->rb_key;
} else
rb_key += jiffies;
} else if (!add_front) {
@@ -1227,37 +1248,37 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
cfqq->slice_resid = 0;
} else {
rb_key = -HZ;
- __cfqq = cfq_rb_first(service_tree);
- rb_key += __cfqq ? __cfqq->rb_key : jiffies;
+ __cfqe = cfq_rb_first(service_tree);
+ rb_key += __cfqe ? __cfqe->rb_key : jiffies;
}
- if (!RB_EMPTY_NODE(&cfqq->rb_node)) {
+ if (!RB_EMPTY_NODE(&cfqe->rb_node)) {
new_cfqq = 0;
/*
* same position, nothing more to do
*/
- if (rb_key == cfqq->rb_key &&
- cfqq->service_tree == service_tree)
+ if (rb_key == cfqe->rb_key &&
+ cfqe->service_tree == service_tree)
return;
- cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree);
- cfqq->service_tree = NULL;
+ cfq_rb_erase(&cfqe->rb_node, cfqe->service_tree);
+ cfqe->service_tree = NULL;
}
left = 1;
parent = NULL;
- cfqq->service_tree = service_tree;
+ cfqe->service_tree = service_tree;
p = &service_tree->rb.rb_node;
while (*p) {
struct rb_node **n;
parent = *p;
- __cfqq = rb_entry(parent, struct cfq_queue, rb_node);
+ __cfqe = rb_entry(parent, struct cfq_entity, rb_node);
/*
* sort by key, that represents service time.
*/
- if (time_before(rb_key, __cfqq->rb_key))
+ if (time_before(rb_key, __cfqe->rb_key))
n = &(*p)->rb_left;
else {
n = &(*p)->rb_right;
@@ -1268,11 +1289,11 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
}
if (left)
- service_tree->left = &cfqq->rb_node;
+ service_tree->left = &cfqe->rb_node;
- cfqq->rb_key = rb_key;
- rb_link_node(&cfqq->rb_node, parent, p);
- rb_insert_color(&cfqq->rb_node, &service_tree->rb);
+ cfqe->rb_key = rb_key;
+ rb_link_node(&cfqe->rb_node, parent, p);
+ rb_insert_color(&cfqe->rb_node, &service_tree->rb);
service_tree->count++;
if ((add_front || !new_cfqq) && !group_changed)
return;
@@ -1374,13 +1395,16 @@ static void cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
*/
static void cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
+ struct cfq_entity *cfqe;
cfq_log_cfqq(cfqd, cfqq, "del_from_rr");
BUG_ON(!cfq_cfqq_on_rr(cfqq));
cfq_clear_cfqq_on_rr(cfqq);
- if (!RB_EMPTY_NODE(&cfqq->rb_node)) {
- cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree);
- cfqq->service_tree = NULL;
+ cfqe = &cfqq->cfqe;
+
+ if (!RB_EMPTY_NODE(&cfqe->rb_node)) {
+ cfq_rb_erase(&cfqe->rb_node, cfqe->service_tree);
+ cfqe->service_tree = NULL;
}
if (cfqq->p_root) {
rb_erase(&cfqq->p_node, cfqq->p_root);
@@ -1708,13 +1732,13 @@ static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd)
return NULL;
if (RB_EMPTY_ROOT(&service_tree->rb))
return NULL;
- return cfq_rb_first(service_tree);
+ return cfqq_of_entity(cfq_rb_first(service_tree));
}
static struct cfq_queue *cfq_get_next_queue_forced(struct cfq_data *cfqd)
{
struct cfq_group *cfqg;
- struct cfq_queue *cfqq;
+ struct cfq_entity *cfqe;
int i, j;
struct cfq_rb_root *st;
@@ -1725,9 +1749,11 @@ static struct cfq_queue *cfq_get_next_queue_forced(struct cfq_data *cfqd)
if (!cfqg)
return NULL;
- for_each_cfqg_st(cfqg, i, j, st)
- if ((cfqq = cfq_rb_first(st)) != NULL)
- return cfqq;
+ for_each_cfqg_st(cfqg, i, j, st) {
+ cfqe = cfq_rb_first(st);
+ if (cfqe != NULL)
+ return cfqq_of_entity(cfqe);
+ }
return NULL;
}
@@ -1864,9 +1890,12 @@ static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd,
static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
+ struct cfq_entity *cfqe;
enum wl_prio_t prio = cfqq_prio(cfqq);
- struct cfq_rb_root *service_tree = cfqq->service_tree;
+ struct cfq_rb_root *service_tree;
+ cfqe = &cfqq->cfqe;
+ service_tree = cfqe->service_tree;
BUG_ON(!service_tree);
BUG_ON(!service_tree->count);
@@ -2076,7 +2105,7 @@ static void cfq_setup_merge(struct cfq_queue *cfqq, struct cfq_queue *new_cfqq)
static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
struct cfq_group *cfqg, enum wl_prio_t prio)
{
- struct cfq_queue *queue;
+ struct cfq_entity *cfqe;
int i;
bool key_valid = false;
unsigned long lowest_key = 0;
@@ -2084,10 +2113,10 @@ static enum wl_type_t cfq_choose_wl(struct cfq_data *cfqd,
for (i = 0; i <= SYNC_WORKLOAD; ++i) {
/* select the one with lowest rb_key */
- queue = cfq_rb_first(service_tree_for(cfqg, prio, i));
- if (queue &&
- (!key_valid || time_before(queue->rb_key, lowest_key))) {
- lowest_key = queue->rb_key;
+ cfqe = cfq_rb_first(service_tree_for(cfqg, prio, i));
+ if (cfqe &&
+ (!key_valid || time_before(cfqe->rb_key, lowest_key))) {
+ lowest_key = cfqe->rb_key;
cur_best = i;
key_valid = true;
}
@@ -2835,7 +2864,10 @@ static void cfq_ioc_set_ioprio(struct io_context *ioc)
static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
pid_t pid, bool is_sync)
{
- RB_CLEAR_NODE(&cfqq->rb_node);
+ struct cfq_entity *cfqe;
+
+ cfqe = &cfqq->cfqe;
+ RB_CLEAR_NODE(&cfqe->rb_node);
RB_CLEAR_NODE(&cfqq->p_node);
INIT_LIST_HEAD(&cfqq->fifo);
@@ -3244,7 +3276,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
/* Allow preemption only if we are idling on sync-noidle tree */
if (cfqd->serving_type == SYNC_NOIDLE_WORKLOAD &&
cfqq_type(new_cfqq) == SYNC_NOIDLE_WORKLOAD &&
- new_cfqq->service_tree->count == 2 &&
+ new_cfqq->cfqe.service_tree->count == 2 &&
RB_EMPTY_ROOT(&cfqq->sort_list))
return true;
--
1.7.1