Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

[pandora-kernel.git] / block / cfq-iosched.c

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index dee9d93..5f127cf 100644 (file)
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -7,6 +7,7 @@
  *  Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
  */
 #include <linux/module.h>
+#include <linux/slab.h>
 #include <linux/blkdev.h>
 #include <linux/elevator.h>
 #include <linux/jiffies.h>
@@ -47,6 +48,7 @@ static const int cfq_hist_divisor = 4;
 #define CFQ_SERVICE_SHIFT       12
 
 #define CFQQ_SEEK_THR          (sector_t)(8 * 100)
+#define CFQQ_CLOSE_THR         (sector_t)(8 * 1024)
 #define CFQQ_SECT_THR_NONROT   (sector_t)(2 * 32)
 #define CFQQ_SEEKY(cfqq)       (hweight32(cfqq->seek_history) > 32/8)
 
@@ -947,6 +949,11 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
        unsigned int major, minor;
 
        cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key));
+       if (cfqg && !cfqg->blkg.dev && bdi->dev && dev_name(bdi->dev)) {
+               sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
+               cfqg->blkg.dev = MKDEV(major, minor);
+               goto done;
+       }
        if (cfqg || !create)
                goto done;
 
@@ -1517,7 +1524,8 @@ static void __cfq_set_active_queue(struct cfq_data *cfqd,
                                   struct cfq_queue *cfqq)
 {
        if (cfqq) {
-               cfq_log_cfqq(cfqd, cfqq, "set_active");
+               cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d",
+                               cfqd->serving_prio, cfqd->serving_type);
                cfqq->slice_start = 0;
                cfqq->dispatch_start = jiffies;
                cfqq->allocated_slice = 0;
@@ -1660,9 +1668,9 @@ static inline sector_t cfq_dist_from_last(struct cfq_data *cfqd,
 }
 
 static inline int cfq_rq_close(struct cfq_data *cfqd, struct cfq_queue *cfqq,
-                              struct request *rq, bool for_preempt)
+                              struct request *rq)
 {
-       return cfq_dist_from_last(cfqd, rq) <= CFQQ_SEEK_THR;
+       return cfq_dist_from_last(cfqd, rq) <= CFQQ_CLOSE_THR;
 }
 
 static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
@@ -1689,7 +1697,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
         * will contain the closest sector.
         */
        __cfqq = rb_entry(parent, struct cfq_queue, p_node);
-       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false))
+       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
                return __cfqq;
 
        if (blk_rq_pos(__cfqq->next_rq) < sector)
@@ -1700,7 +1708,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
                return NULL;
 
        __cfqq = rb_entry(node, struct cfq_queue, p_node);
-       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq, false))
+       if (cfq_rq_close(cfqd, cur_cfqq, __cfqq->next_rq))
                return __cfqq;
 
        return NULL;
@@ -1721,6 +1729,8 @@ static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd,
 {
        struct cfq_queue *cfqq;
 
+       if (cfq_class_idle(cur_cfqq))
+               return NULL;
        if (!cfq_cfqq_sync(cur_cfqq))
                return NULL;
        if (CFQQ_SEEKY(cur_cfqq))
@@ -1787,7 +1797,11 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
         * Otherwise, we do only if they are the last ones
         * in their service tree.
         */
-       return service_tree->count == 1 && cfq_cfqq_sync(cfqq);
+       if (service_tree->count == 1 && cfq_cfqq_sync(cfqq))
+               return 1;
+       cfq_log_cfqq(cfqd, cfqq, "Not idling. st->count:%d",
+                       service_tree->count);
+       return 0;
 }
 
 static void cfq_arm_slice_timer(struct cfq_data *cfqd)
@@ -1832,8 +1846,11 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
         * time slice.
         */
        if (sample_valid(cic->ttime_samples) &&
-           (cfqq->slice_end - jiffies < cic->ttime_mean))
+           (cfqq->slice_end - jiffies < cic->ttime_mean)) {
+               cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%d",
+                               cic->ttime_mean);
                return;
+       }
 
        cfq_mark_cfqq_wait_request(cfqq);
 
@@ -2041,6 +2058,7 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
                slice = max(slice, 2 * cfqd->cfq_slice_idle);
 
        slice = max_t(unsigned, slice, CFQ_MIN_TT);
+       cfq_log(cfqd, "workload slice:%d", slice);
        cfqd->workload_expires = jiffies + slice;
        cfqd->noidle_tree_requires_idle = false;
 }
@@ -2188,10 +2206,13 @@ static int cfq_forced_dispatch(struct cfq_data *cfqd)
        struct cfq_queue *cfqq;
        int dispatched = 0;
 
-       while ((cfqq = cfq_get_next_queue_forced(cfqd)) != NULL)
+       /* Expire the timeslice of the current active queue first */
+       cfq_slice_expired(cfqd, 0);
+       while ((cfqq = cfq_get_next_queue_forced(cfqd)) != NULL) {
+               __cfq_set_active_queue(cfqd, cfqq);
                dispatched += __cfq_forced_dispatch_cfqq(cfqq);
+       }
 
-       cfq_slice_expired(cfqd, 0);
        BUG_ON(cfqd->busy_queues);
 
        cfq_log(cfqd, "forced_dispatch=%d", dispatched);
@@ -3103,7 +3124,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
         * if this request is as-good as one we would expect from the
         * current cfqq, let it preempt
         */
-       if (cfq_rq_close(cfqd, cfqq, rq, true))
+       if (cfq_rq_close(cfqd, cfqq, rq))
                return true;
 
        return false;
@@ -3307,6 +3328,7 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
                if (cfq_should_wait_busy(cfqd, cfqq)) {
                        cfqq->slice_end = jiffies + cfqd->cfq_slice_idle;
                        cfq_mark_cfqq_wait_busy(cfqq);
+                       cfq_log_cfqq(cfqd, cfqq, "will busy wait");
                }
 
                /*
@@ -3672,8 +3694,10 @@ static void *cfq_init_queue(struct request_queue *q)
         * to make sure that cfq_put_cfqg() does not try to kfree root group
         */
        atomic_set(&cfqg->ref, 1);
+       rcu_read_lock();
        blkiocg_add_blkio_group(&blkio_root_cgroup, &cfqg->blkg, (void *)cfqd,
                                        0);
+       rcu_read_unlock();
 #endif
        /*
         * Not strictly needed (since RB_ROOT just clears the node and we