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@@ -27,6 +27,8 @@ static const int cfq_slice_sync = HZ / 10;
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static int cfq_slice_async = HZ / 25;
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static const int cfq_slice_async_rq = 2;
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static int cfq_slice_idle = HZ / 125;
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+static const int cfq_target_latency = HZ * 3/10; /* 300 ms */
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+static const int cfq_hist_divisor = 4;
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/*
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* offset from end of service tree
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@@ -73,8 +75,9 @@ static DEFINE_SPINLOCK(ioc_gone_lock);
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struct cfq_rb_root {
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struct rb_root rb;
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struct rb_node *left;
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+ unsigned count;
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};
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-#define CFQ_RB_ROOT (struct cfq_rb_root) { RB_ROOT, NULL, }
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+#define CFQ_RB_ROOT (struct cfq_rb_root) { RB_ROOT, NULL, 0, }
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/*
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* Per process-grouping structure
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@@ -126,9 +129,30 @@ struct cfq_queue {
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pid_t pid;
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+ struct cfq_rb_root *service_tree;
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struct cfq_queue *new_cfqq;
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};
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+/*
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+ * First index in the service_trees.
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+ * IDLE is handled separately, so it has negative index
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+ */
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+enum wl_prio_t {
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+ IDLE_WORKLOAD = -1,
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+ BE_WORKLOAD = 0,
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+ RT_WORKLOAD = 1
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+};
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+
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+/*
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+ * Second index in the service_trees.
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+ */
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+enum wl_type_t {
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+ ASYNC_WORKLOAD = 0,
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+ SYNC_NOIDLE_WORKLOAD = 1,
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+ SYNC_WORKLOAD = 2
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+};
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+
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+
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/*
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* Per block device queue structure
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*/
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@@ -136,9 +160,17 @@ struct cfq_data {
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struct request_queue *queue;
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/*
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- * rr list of queues with requests and the count of them
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+ * rr lists of queues with requests, onle rr for each priority class.
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+ * Counts are embedded in the cfq_rb_root
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+ */
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+ struct cfq_rb_root service_trees[2][3];
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+ struct cfq_rb_root service_tree_idle;
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+ /*
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+ * The priority currently being served
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*/
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- struct cfq_rb_root service_tree;
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+ enum wl_prio_t serving_prio;
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+ enum wl_type_t serving_type;
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+ unsigned long workload_expires;
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/*
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* Each priority tree is sorted by next_request position. These
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@@ -148,6 +180,7 @@ struct cfq_data {
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struct rb_root prio_trees[CFQ_PRIO_LISTS];
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unsigned int busy_queues;
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+ unsigned int busy_queues_avg[2];
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int rq_in_driver[2];
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int sync_flight;
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@@ -199,6 +232,16 @@ struct cfq_data {
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unsigned long last_end_sync_rq;
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};
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+static struct cfq_rb_root *service_tree_for(enum wl_prio_t prio,
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+ enum wl_type_t type,
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+ struct cfq_data *cfqd)
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+{
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+ if (prio == IDLE_WORKLOAD)
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+ return &cfqd->service_tree_idle;
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+
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+ return &cfqd->service_trees[prio][type];
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+}
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+
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enum cfqq_state_flags {
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CFQ_CFQQ_FLAG_on_rr = 0, /* on round-robin busy list */
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CFQ_CFQQ_FLAG_wait_request, /* waiting for a request */
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@@ -243,6 +286,35 @@ CFQ_CFQQ_FNS(coop);
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#define cfq_log(cfqd, fmt, args...) \
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blk_add_trace_msg((cfqd)->queue, "cfq " fmt, ##args)
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+static inline enum wl_prio_t cfqq_prio(struct cfq_queue *cfqq)
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+{
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+ if (cfq_class_idle(cfqq))
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+ return IDLE_WORKLOAD;
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+ if (cfq_class_rt(cfqq))
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+ return RT_WORKLOAD;
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+ return BE_WORKLOAD;
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+}
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+
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+
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+static enum wl_type_t cfqq_type(struct cfq_queue *cfqq)
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+{
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+ if (!cfq_cfqq_sync(cfqq))
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+ return ASYNC_WORKLOAD;
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+ if (!cfq_cfqq_idle_window(cfqq))
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+ return SYNC_NOIDLE_WORKLOAD;
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+ return SYNC_WORKLOAD;
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+}
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+
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+static inline int cfq_busy_queues_wl(enum wl_prio_t wl, struct cfq_data *cfqd)
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+{
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+ if (wl == IDLE_WORKLOAD)
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+ return cfqd->service_tree_idle.count;
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+
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+ return cfqd->service_trees[wl][ASYNC_WORKLOAD].count
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+ + cfqd->service_trees[wl][SYNC_NOIDLE_WORKLOAD].count
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+ + cfqd->service_trees[wl][SYNC_WORKLOAD].count;
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+}
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+
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static void cfq_dispatch_insert(struct request_queue *, struct request *);
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static struct cfq_queue *cfq_get_queue(struct cfq_data *, bool,
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struct io_context *, gfp_t);
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@@ -315,10 +387,49 @@ cfq_prio_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq)
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return cfq_prio_slice(cfqd, cfq_cfqq_sync(cfqq), cfqq->ioprio);
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}
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+/*
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+ * get averaged number of queues of RT/BE priority.
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+ * average is updated, with a formula that gives more weight to higher numbers,
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+ * to quickly follows sudden increases and decrease slowly
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+ */
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+
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+static inline unsigned cfq_get_avg_queues(struct cfq_data *cfqd, bool rt)
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+{
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+ unsigned min_q, max_q;
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+ unsigned mult = cfq_hist_divisor - 1;
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+ unsigned round = cfq_hist_divisor / 2;
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+ unsigned busy = cfq_busy_queues_wl(rt, cfqd);
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+
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+ min_q = min(cfqd->busy_queues_avg[rt], busy);
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+ max_q = max(cfqd->busy_queues_avg[rt], busy);
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+ cfqd->busy_queues_avg[rt] = (mult * max_q + min_q + round) /
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+ cfq_hist_divisor;
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+ return cfqd->busy_queues_avg[rt];
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+}
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+
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static inline void
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cfq_set_prio_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq)
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{
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- cfqq->slice_end = cfq_prio_to_slice(cfqd, cfqq) + jiffies;
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+ unsigned slice = cfq_prio_to_slice(cfqd, cfqq);
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+ if (cfqd->cfq_latency) {
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+ /* interested queues (we consider only the ones with the same
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+ * priority class) */
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+ unsigned iq = cfq_get_avg_queues(cfqd, cfq_class_rt(cfqq));
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+ unsigned sync_slice = cfqd->cfq_slice[1];
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+ unsigned expect_latency = sync_slice * iq;
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+ if (expect_latency > cfq_target_latency) {
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+ unsigned base_low_slice = 2 * cfqd->cfq_slice_idle;
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+ /* scale low_slice according to IO priority
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+ * and sync vs async */
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+ unsigned low_slice =
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+ min(slice, base_low_slice * slice / sync_slice);
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+ /* the adapted slice value is scaled to fit all iqs
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+ * into the target latency */
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+ slice = max(slice * cfq_target_latency / expect_latency,
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+ low_slice);
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+ }
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+ }
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+ cfqq->slice_end = jiffies + slice;
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cfq_log_cfqq(cfqd, cfqq, "set_slice=%lu", cfqq->slice_end - jiffies);
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}
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@@ -457,6 +568,7 @@ static void cfq_rb_erase(struct rb_node *n, struct cfq_rb_root *root)
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if (root->left == n)
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root->left = NULL;
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rb_erase_init(n, &root->rb);
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+ --root->count;
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}
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/*
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@@ -497,7 +609,7 @@ static unsigned long cfq_slice_offset(struct cfq_data *cfqd,
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}
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/*
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- * The cfqd->service_tree holds all pending cfq_queue's that have
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+ * The cfqd->service_trees holds all pending cfq_queue's that have
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* requests waiting to be processed. It is sorted in the order that
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* we will service the queues.
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*/
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@@ -507,11 +619,13 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
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struct rb_node **p, *parent;
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struct cfq_queue *__cfqq;
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unsigned long rb_key;
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+ struct cfq_rb_root *service_tree;
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int left;
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+ service_tree = service_tree_for(cfqq_prio(cfqq), cfqq_type(cfqq), cfqd);
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if (cfq_class_idle(cfqq)) {
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rb_key = CFQ_IDLE_DELAY;
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- parent = rb_last(&cfqd->service_tree.rb);
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+ parent = rb_last(&service_tree->rb);
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if (parent && parent != &cfqq->rb_node) {
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__cfqq = rb_entry(parent, struct cfq_queue, rb_node);
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rb_key += __cfqq->rb_key;
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@@ -529,7 +643,7 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
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cfqq->slice_resid = 0;
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} else {
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rb_key = -HZ;
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- __cfqq = cfq_rb_first(&cfqd->service_tree);
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+ __cfqq = cfq_rb_first(service_tree);
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rb_key += __cfqq ? __cfqq->rb_key : jiffies;
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}
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@@ -537,15 +651,18 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
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/*
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* same position, nothing more to do
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*/
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- if (rb_key == cfqq->rb_key)
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+ if (rb_key == cfqq->rb_key &&
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+ cfqq->service_tree == service_tree)
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return;
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- cfq_rb_erase(&cfqq->rb_node, &cfqd->service_tree);
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+ cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree);
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+ cfqq->service_tree = NULL;
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}
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left = 1;
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parent = NULL;
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- p = &cfqd->service_tree.rb.rb_node;
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+ cfqq->service_tree = service_tree;
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+ p = &service_tree->rb.rb_node;
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while (*p) {
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struct rb_node **n;
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@@ -553,35 +670,25 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
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__cfqq = rb_entry(parent, struct cfq_queue, rb_node);
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/*
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- * sort RT queues first, we always want to give
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- * preference to them. IDLE queues goes to the back.
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- * after that, sort on the next service time.
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+ * sort by key, that represents service time.
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*/
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- if (cfq_class_rt(cfqq) > cfq_class_rt(__cfqq))
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+ if (time_before(rb_key, __cfqq->rb_key))
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n = &(*p)->rb_left;
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- else if (cfq_class_rt(cfqq) < cfq_class_rt(__cfqq))
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- n = &(*p)->rb_right;
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- else if (cfq_class_idle(cfqq) < cfq_class_idle(__cfqq))
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- n = &(*p)->rb_left;
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- else if (cfq_class_idle(cfqq) > cfq_class_idle(__cfqq))
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- n = &(*p)->rb_right;
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- else if (time_before(rb_key, __cfqq->rb_key))
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- n = &(*p)->rb_left;
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- else
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+ else {
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n = &(*p)->rb_right;
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-
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- if (n == &(*p)->rb_right)
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left = 0;
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+ }
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p = n;
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}
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if (left)
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- cfqd->service_tree.left = &cfqq->rb_node;
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+ service_tree->left = &cfqq->rb_node;
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cfqq->rb_key = rb_key;
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rb_link_node(&cfqq->rb_node, parent, p);
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- rb_insert_color(&cfqq->rb_node, &cfqd->service_tree.rb);
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+ rb_insert_color(&cfqq->rb_node, &service_tree->rb);
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+ service_tree->count++;
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}
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static struct cfq_queue *
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@@ -683,8 +790,10 @@ static void cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
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BUG_ON(!cfq_cfqq_on_rr(cfqq));
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cfq_clear_cfqq_on_rr(cfqq);
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- if (!RB_EMPTY_NODE(&cfqq->rb_node))
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- cfq_rb_erase(&cfqq->rb_node, &cfqd->service_tree);
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+ if (!RB_EMPTY_NODE(&cfqq->rb_node)) {
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+ cfq_rb_erase(&cfqq->rb_node, cfqq->service_tree);
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+ cfqq->service_tree = NULL;
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+ }
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if (cfqq->p_root) {
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rb_erase(&cfqq->p_node, cfqq->p_root);
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cfqq->p_root = NULL;
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@@ -945,10 +1054,12 @@ static inline void cfq_slice_expired(struct cfq_data *cfqd, bool timed_out)
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*/
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static struct cfq_queue *cfq_get_next_queue(struct cfq_data *cfqd)
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{
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- if (RB_EMPTY_ROOT(&cfqd->service_tree.rb))
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- return NULL;
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+ struct cfq_rb_root *service_tree =
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+ service_tree_for(cfqd->serving_prio, cfqd->serving_type, cfqd);
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- return cfq_rb_first(&cfqd->service_tree);
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+ if (RB_EMPTY_ROOT(&service_tree->rb))
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+ return NULL;
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+ return cfq_rb_first(service_tree);
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}
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/*
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@@ -1065,9 +1176,45 @@ static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd,
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if (CFQQ_SEEKY(cfqq))
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return NULL;
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+ /*
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+ * Do not merge queues of different priority classes
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+ */
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+ if (cfq_class_rt(cfqq) != cfq_class_rt(cur_cfqq))
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+ return NULL;
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+
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return cfqq;
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}
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+/*
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+ * Determine whether we should enforce idle window for this queue.
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+ */
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+
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+static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
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+{
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+ enum wl_prio_t prio = cfqq_prio(cfqq);
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+ struct cfq_rb_root *service_tree = cfqq->service_tree;
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+
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+ /* We never do for idle class queues. */
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+ if (prio == IDLE_WORKLOAD)
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+ return false;
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+
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+ /* We do for queues that were marked with idle window flag. */
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+ if (cfq_cfqq_idle_window(cfqq))
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+ return true;
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+
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+ /*
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+ * Otherwise, we do only if they are the last ones
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+ * in their service tree.
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+ */
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+ if (!service_tree)
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+ service_tree = service_tree_for(prio, cfqq_type(cfqq), cfqd);
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+
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+ if (service_tree->count == 0)
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+ return true;
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+
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+ return (service_tree->count == 1 && cfq_rb_first(service_tree) == cfqq);
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+}
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+
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static void cfq_arm_slice_timer(struct cfq_data *cfqd)
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{
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struct cfq_queue *cfqq = cfqd->active_queue;
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@@ -1088,7 +1235,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
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/*
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* idle is disabled, either manually or by past process history
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*/
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- if (!cfqd->cfq_slice_idle || !cfq_cfqq_idle_window(cfqq))
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+ if (!cfqd->cfq_slice_idle || !cfq_should_idle(cfqd, cfqq))
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return;
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/*
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@@ -1115,14 +1262,20 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
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cfq_mark_cfqq_wait_request(cfqq);
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- /*
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- * we don't want to idle for seeks, but we do want to allow
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- * fair distribution of slice time for a process doing back-to-back
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- * seeks. so allow a little bit of time for him to submit a new rq
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- */
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sl = cfqd->cfq_slice_idle;
|
|
|
- if (sample_valid(cfqq->seek_samples) && CFQQ_SEEKY(cfqq))
|
|
|
+ /* are we servicing noidle tree, and there are more queues?
|
|
|
+ * non-rotational or NCQ: no idle
|
|
|
+ * non-NCQ rotational : very small idle, to allow
|
|
|
+ * fair distribution of slice time for a process doing back-to-back
|
|
|
+ * seeks.
|
|
|
+ */
|
|
|
+ if (cfqd->serving_type == SYNC_NOIDLE_WORKLOAD &&
|
|
|
+ service_tree_for(cfqd->serving_prio, SYNC_NOIDLE_WORKLOAD, cfqd)
|
|
|
+ ->count > 0) {
|
|
|
+ if (blk_queue_nonrot(cfqd->queue) || cfqd->hw_tag)
|
|
|
+ return;
|
|
|
sl = min(sl, msecs_to_jiffies(CFQ_MIN_TT));
|
|
|
+ }
|
|
|
|
|
|
mod_timer(&cfqd->idle_slice_timer, jiffies + sl);
|
|
|
cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu", sl);
|
|
@@ -1226,6 +1379,106 @@ 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, enum wl_prio_t prio,
|
|
|
+ bool prio_changed)
|
|
|
+{
|
|
|
+ struct cfq_queue *queue;
|
|
|
+ int i;
|
|
|
+ bool key_valid = false;
|
|
|
+ unsigned long lowest_key = 0;
|
|
|
+ enum wl_type_t cur_best = SYNC_NOIDLE_WORKLOAD;
|
|
|
+
|
|
|
+ if (prio_changed) {
|
|
|
+ /*
|
|
|
+ * When priorities switched, we prefer starting
|
|
|
+ * from SYNC_NOIDLE (first choice), or just SYNC
|
|
|
+ * over ASYNC
|
|
|
+ */
|
|
|
+ if (service_tree_for(prio, cur_best, cfqd)->count)
|
|
|
+ return cur_best;
|
|
|
+ cur_best = SYNC_WORKLOAD;
|
|
|
+ if (service_tree_for(prio, cur_best, cfqd)->count)
|
|
|
+ return cur_best;
|
|
|
+
|
|
|
+ return ASYNC_WORKLOAD;
|
|
|
+ }
|
|
|
+
|
|
|
+ for (i = 0; i < 3; ++i) {
|
|
|
+ /* otherwise, select the one with lowest rb_key */
|
|
|
+ queue = cfq_rb_first(service_tree_for(prio, i, cfqd));
|
|
|
+ if (queue &&
|
|
|
+ (!key_valid || time_before(queue->rb_key, lowest_key))) {
|
|
|
+ lowest_key = queue->rb_key;
|
|
|
+ cur_best = i;
|
|
|
+ key_valid = true;
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ return cur_best;
|
|
|
+}
|
|
|
+
|
|
|
+static void choose_service_tree(struct cfq_data *cfqd)
|
|
|
+{
|
|
|
+ enum wl_prio_t previous_prio = cfqd->serving_prio;
|
|
|
+ bool prio_changed;
|
|
|
+ unsigned slice;
|
|
|
+ unsigned count;
|
|
|
+
|
|
|
+ /* Choose next priority. RT > BE > IDLE */
|
|
|
+ if (cfq_busy_queues_wl(RT_WORKLOAD, cfqd))
|
|
|
+ cfqd->serving_prio = RT_WORKLOAD;
|
|
|
+ else if (cfq_busy_queues_wl(BE_WORKLOAD, cfqd))
|
|
|
+ cfqd->serving_prio = BE_WORKLOAD;
|
|
|
+ else {
|
|
|
+ cfqd->serving_prio = IDLE_WORKLOAD;
|
|
|
+ cfqd->workload_expires = jiffies + 1;
|
|
|
+ return;
|
|
|
+ }
|
|
|
+
|
|
|
+ /*
|
|
|
+ * For RT and BE, we have to choose also the type
|
|
|
+ * (SYNC, SYNC_NOIDLE, ASYNC), and to compute a workload
|
|
|
+ * expiration time
|
|
|
+ */
|
|
|
+ prio_changed = (cfqd->serving_prio != previous_prio);
|
|
|
+ count = service_tree_for(cfqd->serving_prio, cfqd->serving_type, cfqd)
|
|
|
+ ->count;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * If priority didn't change, check workload expiration,
|
|
|
+ * and that we still have other queues ready
|
|
|
+ */
|
|
|
+ if (!prio_changed && count &&
|
|
|
+ !time_after(jiffies, cfqd->workload_expires))
|
|
|
+ return;
|
|
|
+
|
|
|
+ /* otherwise select new workload type */
|
|
|
+ cfqd->serving_type =
|
|
|
+ cfq_choose_wl(cfqd, cfqd->serving_prio, prio_changed);
|
|
|
+ count = service_tree_for(cfqd->serving_prio, cfqd->serving_type, cfqd)
|
|
|
+ ->count;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * the workload slice is computed as a fraction of target latency
|
|
|
+ * 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));
|
|
|
+
|
|
|
+ if (cfqd->serving_type == ASYNC_WORKLOAD)
|
|
|
+ /* async workload slice is scaled down according to
|
|
|
+ * the sync/async slice ratio. */
|
|
|
+ slice = slice * cfqd->cfq_slice[0] / cfqd->cfq_slice[1];
|
|
|
+ else
|
|
|
+ /* sync workload slice is at least 2 * cfq_slice_idle */
|
|
|
+ slice = max(slice, 2 * cfqd->cfq_slice_idle);
|
|
|
+
|
|
|
+ slice = max_t(unsigned, slice, CFQ_MIN_TT);
|
|
|
+ cfqd->workload_expires = jiffies + slice;
|
|
|
+}
|
|
|
+
|
|
|
/*
|
|
|
* Select a queue for service. If we have a current active queue,
|
|
|
* check whether to continue servicing it, or retrieve and set a new one.
|
|
@@ -1270,7 +1523,7 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd)
|
|
|
* conditions to happen (or time out) before selecting a new queue.
|
|
|
*/
|
|
|
if (timer_pending(&cfqd->idle_slice_timer) ||
|
|
|
- (cfqq->dispatched && cfq_cfqq_idle_window(cfqq))) {
|
|
|
+ (cfqq->dispatched && cfq_should_idle(cfqd, cfqq))) {
|
|
|
cfqq = NULL;
|
|
|
goto keep_queue;
|
|
|
}
|
|
@@ -1278,6 +1531,13 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd)
|
|
|
expire:
|
|
|
cfq_slice_expired(cfqd, 0);
|
|
|
new_queue:
|
|
|
+ /*
|
|
|
+ * Current queue expired. Check if we have to switch to a new
|
|
|
+ * service tree
|
|
|
+ */
|
|
|
+ if (!new_cfqq)
|
|
|
+ choose_service_tree(cfqd);
|
|
|
+
|
|
|
cfqq = cfq_set_active_queue(cfqd, new_cfqq);
|
|
|
keep_queue:
|
|
|
return cfqq;
|
|
@@ -1304,8 +1564,14 @@ static int cfq_forced_dispatch(struct cfq_data *cfqd)
|
|
|
{
|
|
|
struct cfq_queue *cfqq;
|
|
|
int dispatched = 0;
|
|
|
-
|
|
|
- while ((cfqq = cfq_rb_first(&cfqd->service_tree)) != NULL)
|
|
|
+ int i, j;
|
|
|
+ for (i = 0; i < 2; ++i)
|
|
|
+ for (j = 0; j < 3; ++j)
|
|
|
+ while ((cfqq = cfq_rb_first(&cfqd->service_trees[i][j]))
|
|
|
+ != NULL)
|
|
|
+ dispatched += __cfq_forced_dispatch_cfqq(cfqq);
|
|
|
+
|
|
|
+ while ((cfqq = cfq_rb_first(&cfqd->service_tree_idle)) != NULL)
|
|
|
dispatched += __cfq_forced_dispatch_cfqq(cfqq);
|
|
|
|
|
|
cfq_slice_expired(cfqd, 0);
|
|
@@ -1323,7 +1589,7 @@ static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq)
|
|
|
/*
|
|
|
* Drain async requests before we start sync IO
|
|
|
*/
|
|
|
- if (cfq_cfqq_idle_window(cfqq) && cfqd->rq_in_driver[BLK_RW_ASYNC])
|
|
|
+ if (cfq_should_idle(cfqd, cfqq) && cfqd->rq_in_driver[BLK_RW_ASYNC])
|
|
|
return false;
|
|
|
|
|
|
/*
|
|
@@ -2086,13 +2352,10 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq,
|
|
|
enable_idle = old_idle = cfq_cfqq_idle_window(cfqq);
|
|
|
|
|
|
if (!atomic_read(&cic->ioc->nr_tasks) || !cfqd->cfq_slice_idle ||
|
|
|
- (!cfqd->cfq_latency && cfqd->hw_tag && CFQQ_SEEKY(cfqq)))
|
|
|
+ (sample_valid(cfqq->seek_samples) && CFQQ_SEEKY(cfqq)))
|
|
|
enable_idle = 0;
|
|
|
else if (sample_valid(cic->ttime_samples)) {
|
|
|
- unsigned int slice_idle = cfqd->cfq_slice_idle;
|
|
|
- if (sample_valid(cfqq->seek_samples) && CFQQ_SEEKY(cfqq))
|
|
|
- slice_idle = msecs_to_jiffies(CFQ_MIN_TT);
|
|
|
- if (cic->ttime_mean > slice_idle)
|
|
|
+ if (cic->ttime_mean > cfqd->cfq_slice_idle)
|
|
|
enable_idle = 0;
|
|
|
else
|
|
|
enable_idle = 1;
|
|
@@ -2130,6 +2393,10 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
|
|
|
if (cfq_class_idle(cfqq))
|
|
|
return true;
|
|
|
|
|
|
+ if (cfqd->serving_type == SYNC_NOIDLE_WORKLOAD
|
|
|
+ && new_cfqq->service_tree == cfqq->service_tree)
|
|
|
+ return true;
|
|
|
+
|
|
|
/*
|
|
|
* if the new request is sync, but the currently running queue is
|
|
|
* not, let the sync request have priority.
|
|
@@ -2243,10 +2510,9 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq)
|
|
|
cfq_log_cfqq(cfqd, cfqq, "insert_request");
|
|
|
cfq_init_prio_data(cfqq, RQ_CIC(rq)->ioc);
|
|
|
|
|
|
- cfq_add_rq_rb(rq);
|
|
|
-
|
|
|
rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]);
|
|
|
list_add_tail(&rq->queuelist, &cfqq->fifo);
|
|
|
+ cfq_add_rq_rb(rq);
|
|
|
|
|
|
cfq_rq_enqueued(cfqd, cfqq, rq);
|
|
|
}
|
|
@@ -2645,13 +2911,16 @@ static void cfq_exit_queue(struct elevator_queue *e)
|
|
|
static void *cfq_init_queue(struct request_queue *q)
|
|
|
{
|
|
|
struct cfq_data *cfqd;
|
|
|
- int i;
|
|
|
+ int i, j;
|
|
|
|
|
|
cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node);
|
|
|
if (!cfqd)
|
|
|
return NULL;
|
|
|
|
|
|
- cfqd->service_tree = CFQ_RB_ROOT;
|
|
|
+ for (i = 0; i < 2; ++i)
|
|
|
+ for (j = 0; j < 3; ++j)
|
|
|
+ cfqd->service_trees[i][j] = CFQ_RB_ROOT;
|
|
|
+ cfqd->service_tree_idle = CFQ_RB_ROOT;
|
|
|
|
|
|
/*
|
|
|
* Not strictly needed (since RB_ROOT just clears the node and we
|