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-rw-r--r--block/cfq-iosched.c42
1 files changed, 32 insertions, 10 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index dee9d9378fe..838834be115 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -7,6 +7,7 @@
7 * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk> 7 * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
8 */ 8 */
9#include <linux/module.h> 9#include <linux/module.h>
10#include <linux/slab.h>
10#include <linux/blkdev.h> 11#include <linux/blkdev.h>
11#include <linux/elevator.h> 12#include <linux/elevator.h>
12#include <linux/jiffies.h> 13#include <linux/jiffies.h>
@@ -47,6 +48,7 @@ static const int cfq_hist_divisor = 4;
47#define CFQ_SERVICE_SHIFT 12 48#define CFQ_SERVICE_SHIFT 12
48 49
49#define CFQQ_SEEK_THR (sector_t)(8 * 100) 50#define CFQQ_SEEK_THR (sector_t)(8 * 100)
51#define CFQQ_CLOSE_THR (sector_t)(8 * 1024)
50#define CFQQ_SECT_THR_NONROT (sector_t)(2 * 32) 52#define CFQQ_SECT_THR_NONROT (sector_t)(2 * 32)
51#define CFQQ_SEEKY(cfqq) (hweight32(cfqq->seek_history) > 32/8) 53#define CFQQ_SEEKY(cfqq) (hweight32(cfqq->seek_history) > 32/8)
52 54
@@ -947,6 +949,11 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
947 unsigned int major, minor; 949 unsigned int major, minor;
948 950
949 cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key)); 951 cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key));
952 if (cfqg && !cfqg->blkg.dev && bdi->dev && dev_name(bdi->dev)) {
953 sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
954 cfqg->blkg.dev = MKDEV(major, minor);
955 goto done;
956 }
950 if (cfqg || !create) 957 if (cfqg || !create)
951 goto done; 958 goto done;
952 959
@@ -1517,7 +1524,8 @@ static void __cfq_set_active_queue(struct cfq_data *cfqd,
1517 struct cfq_queue *cfqq) 1524 struct cfq_queue *cfqq)
1518{ 1525{
1519 if (cfqq) { 1526 if (cfqq) {
1520 cfq_log_cfqq(cfqd, cfqq, "set_active"); 1527 cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d",
1528 cfqd->serving_prio, cfqd->serving_type);
1521 cfqq->slice_start = 0; 1529 cfqq->slice_start = 0;
1522 cfqq->dispatch_start = jiffies; 1530 cfqq->dispatch_start = jiffies;
1523 cfqq->allocated_slice = 0; 1531 cfqq->allocated_slice = 0;
@@ -1660,9 +1668,9 @@ static inline sector_t cfq_dist_from_last(struct cfq_data *cfqd,
1660} 1668}
1661 1669
1662static inline int cfq_rq_close(struct cfq_data *cfqd, struct cfq_queue *cfqq, 1670static inline int cfq_rq_close(struct cfq_data *cfqd, struct cfq_queue *cfqq,
1663 struct request *rq, bool for_preempt) 1671 struct request *rq)
1664{ 1672{
1665 return cfq_dist_from_last(cfqd, rq) <= CFQQ_SEEK_THR; 1673 return cfq_dist_from_last(cfqd, rq) <= CFQQ_CLOSE_THR;
1666} 1674}
1667 1675
1668static struct cfq_queue *cfqq_close(struct cfq_data *cfqd, 1676static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
@@ -1689,7 +1697,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
1689 * will contain the closest sector. 1697 * will contain the closest sector.
1690 */ 1698 */
1691 __cfqq = rb_entry(parent, struct cfq_queue, p_node); 1699 __cfqq = rb_entry(parent, struct cfq_queue, p_node);
1692 if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false)) 1700 if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
1693 return __cfqq; 1701 return __cfqq;
1694 1702
1695 if (blk_rq_pos(__cfqq->next_rq) < sector) 1703 if (blk_rq_pos(__cfqq->next_rq) < sector)
@@ -1700,7 +1708,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
1700 return NULL; 1708 return NULL;
1701 1709
1702 __cfqq = rb_entry(node, struct cfq_queue, p_node); 1710 __cfqq = rb_entry(node, struct cfq_queue, p_node);
1703 if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false)) 1711 if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
1704 return __cfqq; 1712 return __cfqq;
1705 1713
1706 return NULL; 1714 return NULL;
@@ -1721,6 +1729,8 @@ static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd,
1721{ 1729{
1722 struct cfq_queue *cfqq; 1730 struct cfq_queue *cfqq;
1723 1731
1732 if (cfq_class_idle(cur_cfqq))
1733 return NULL;
1724 if (!cfq_cfqq_sync(cur_cfqq)) 1734 if (!cfq_cfqq_sync(cur_cfqq))
1725 return NULL; 1735 return NULL;
1726 if (CFQQ_SEEKY(cur_cfqq)) 1736 if (CFQQ_SEEKY(cur_cfqq))
@@ -1787,7 +1797,11 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
1787 * Otherwise, we do only if they are the last ones 1797 * Otherwise, we do only if they are the last ones
1788 * in their service tree. 1798 * in their service tree.
1789 */ 1799 */
1790 return service_tree->count == 1 && cfq_cfqq_sync(cfqq); 1800 if (service_tree->count == 1 && cfq_cfqq_sync(cfqq))
1801 return 1;
1802 cfq_log_cfqq(cfqd, cfqq, "Not idling. st->count:%d",
1803 service_tree->count);
1804 return 0;
1791} 1805}
1792 1806
1793static void cfq_arm_slice_timer(struct cfq_data *cfqd) 1807static void cfq_arm_slice_timer(struct cfq_data *cfqd)
@@ -1832,8 +1846,11 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
1832 * time slice. 1846 * time slice.
1833 */ 1847 */
1834 if (sample_valid(cic->ttime_samples) && 1848 if (sample_valid(cic->ttime_samples) &&
1835 (cfqq->slice_end - jiffies < cic->ttime_mean)) 1849 (cfqq->slice_end - jiffies < cic->ttime_mean)) {
1850 cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%d",
1851 cic->ttime_mean);
1836 return; 1852 return;
1853 }
1837 1854
1838 cfq_mark_cfqq_wait_request(cfqq); 1855 cfq_mark_cfqq_wait_request(cfqq);
1839 1856
@@ -2041,6 +2058,7 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
2041 slice = max(slice, 2 * cfqd->cfq_slice_idle); 2058 slice = max(slice, 2 * cfqd->cfq_slice_idle);
2042 2059
2043 slice = max_t(unsigned, slice, CFQ_MIN_TT); 2060 slice = max_t(unsigned, slice, CFQ_MIN_TT);
2061 cfq_log(cfqd, "workload slice:%d", slice);
2044 cfqd->workload_expires = jiffies + slice; 2062 cfqd->workload_expires = jiffies + slice;
2045 cfqd->noidle_tree_requires_idle = false; 2063 cfqd->noidle_tree_requires_idle = false;
2046} 2064}
@@ -2188,10 +2206,13 @@ static int cfq_forced_dispatch(struct cfq_data *cfqd)
2188 struct cfq_queue *cfqq; 2206 struct cfq_queue *cfqq;
2189 int dispatched = 0; 2207 int dispatched = 0;
2190 2208
2191 while ((cfqq = cfq_get_next_queue_forced(cfqd)) != NULL) 2209 /* Expire the timeslice of the current active queue first */
2210 cfq_slice_expired(cfqd, 0);
2211 while ((cfqq = cfq_get_next_queue_forced(cfqd)) != NULL) {
2212 __cfq_set_active_queue(cfqd, cfqq);
2192 dispatched += __cfq_forced_dispatch_cfqq(cfqq); 2213 dispatched += __cfq_forced_dispatch_cfqq(cfqq);
2214 }
2193 2215
2194 cfq_slice_expired(cfqd, 0);
2195 BUG_ON(cfqd->busy_queues); 2216 BUG_ON(cfqd->busy_queues);
2196 2217
2197 cfq_log(cfqd, "forced_dispatch=%d", dispatched); 2218 cfq_log(cfqd, "forced_dispatch=%d", dispatched);
@@ -3103,7 +3124,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
3103 * if this request is as-good as one we would expect from the 3124 * if this request is as-good as one we would expect from the
3104 * current cfqq, let it preempt 3125 * current cfqq, let it preempt
3105 */ 3126 */
3106 if (cfq_rq_close(cfqd, cfqq, rq, true)) 3127 if (cfq_rq_close(cfqd, cfqq, rq))
3107 return true; 3128 return true;
3108 3129
3109 return false; 3130 return false;
@@ -3307,6 +3328,7 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
3307 if (cfq_should_wait_busy(cfqd, cfqq)) { 3328 if (cfq_should_wait_busy(cfqd, cfqq)) {
3308 cfqq->slice_end = jiffies + cfqd->cfq_slice_idle; 3329 cfqq->slice_end = jiffies + cfqd->cfq_slice_idle;
3309 cfq_mark_cfqq_wait_busy(cfqq); 3330 cfq_mark_cfqq_wait_busy(cfqq);
3331 cfq_log_cfqq(cfqd, cfqq, "will busy wait");
3310 } 3332 }
3311 3333
3312 /* 3334 /*