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author | Justin TerAvest <teravest@google.com> | 2011-03-01 20:05:08 (GMT) |
---|---|---|
committer | Jens Axboe <jaxboe@fusionio.com> | 2011-03-01 20:05:08 (GMT) |
commit | 0bbfeb8320421989d3e12bd95fae86b9ac0712aa (patch) | |
tree | a23bb6686bd2586fe7c27d0773c63f9aeb254cd1 /block/cfq-iosched.c | |
parent | 6fae9c25134baffbeeb20031479e7ff6f6d8eec0 (diff) | |
download | linux-0bbfeb8320421989d3e12bd95fae86b9ac0712aa.tar.xz |
cfq-iosched: Always provide group isolation.
Effectively, make group_isolation=1 the default and remove the tunable.
The setting group_isolation=0 was because by default we idle on
sync-noidle tree and on fast devices, this can be very harmful for
throughput.
However, this problem can also be addressed by tuning slice_idle and
possibly group_idle on faster storage devices.
This change simplifies the CFQ code by removing the feature entirely.
Signed-off-by: Justin TerAvest <teravest@google.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'block/cfq-iosched.c')
-rw-r--r-- | block/cfq-iosched.c | 37 |
1 files changed, 1 insertions, 36 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index f27ff3e..3202c7e 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -146,7 +146,6 @@ struct cfq_queue { struct cfq_rb_root *service_tree; struct cfq_queue *new_cfqq; struct cfq_group *cfqg; - struct cfq_group *orig_cfqg; /* Number of sectors dispatched from queue in single dispatch round */ unsigned long nr_sectors; }; @@ -285,7 +284,6 @@ struct cfq_data { unsigned int cfq_slice_idle; unsigned int cfq_group_idle; unsigned int cfq_latency; - unsigned int cfq_group_isolation; unsigned int cic_index; struct list_head cic_list; @@ -1187,32 +1185,6 @@ static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq, int new_cfqq = 1; int group_changed = 0; -#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)) - cfq_group_service_tree_del(cfqd, cfqq->cfqg); - cfqq->orig_cfqg = cfqq->cfqg; - cfqq->cfqg = &cfqd->root_group; - cfqd->root_group.ref++; - group_changed = 1; - } else if (!cfqd->cfq_group_isolation - && 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)) - cfq_group_service_tree_del(cfqd, cfqq->cfqg); - cfq_put_cfqg(cfqq->cfqg); - cfqq->cfqg = cfqq->orig_cfqg; - cfqq->orig_cfqg = NULL; - group_changed = 1; - cfq_log_cfqq(cfqd, cfqq, "moved to origin group"); - } -#endif - service_tree = service_tree_for(cfqq->cfqg, cfqq_prio(cfqq), cfqq_type(cfqq)); if (cfq_class_idle(cfqq)) { @@ -2542,7 +2514,7 @@ static int cfq_dispatch_requests(struct request_queue *q, int force) static void cfq_put_queue(struct cfq_queue *cfqq) { struct cfq_data *cfqd = cfqq->cfqd; - struct cfq_group *cfqg, *orig_cfqg; + struct cfq_group *cfqg; BUG_ON(cfqq->ref <= 0); @@ -2554,7 +2526,6 @@ static void cfq_put_queue(struct cfq_queue *cfqq) BUG_ON(rb_first(&cfqq->sort_list)); BUG_ON(cfqq->allocated[READ] + cfqq->allocated[WRITE]); cfqg = cfqq->cfqg; - orig_cfqg = cfqq->orig_cfqg; if (unlikely(cfqd->active_queue == cfqq)) { __cfq_slice_expired(cfqd, cfqq, 0); @@ -2564,8 +2535,6 @@ static void cfq_put_queue(struct cfq_queue *cfqq) BUG_ON(cfq_cfqq_on_rr(cfqq)); kmem_cache_free(cfq_pool, cfqq); cfq_put_cfqg(cfqg); - if (orig_cfqg) - cfq_put_cfqg(orig_cfqg); } /* @@ -3953,7 +3922,6 @@ static void *cfq_init_queue(struct request_queue *q) cfqd->cfq_slice_idle = cfq_slice_idle; cfqd->cfq_group_idle = cfq_group_idle; cfqd->cfq_latency = 1; - cfqd->cfq_group_isolation = 0; cfqd->hw_tag = -1; /* * we optimistically start assuming sync ops weren't delayed in last @@ -4029,7 +3997,6 @@ SHOW_FUNCTION(cfq_slice_sync_show, cfqd->cfq_slice[1], 1); SHOW_FUNCTION(cfq_slice_async_show, cfqd->cfq_slice[0], 1); SHOW_FUNCTION(cfq_slice_async_rq_show, cfqd->cfq_slice_async_rq, 0); SHOW_FUNCTION(cfq_low_latency_show, cfqd->cfq_latency, 0); -SHOW_FUNCTION(cfq_group_isolation_show, cfqd->cfq_group_isolation, 0); #undef SHOW_FUNCTION #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ @@ -4063,7 +4030,6 @@ STORE_FUNCTION(cfq_slice_async_store, &cfqd->cfq_slice[0], 1, UINT_MAX, 1); STORE_FUNCTION(cfq_slice_async_rq_store, &cfqd->cfq_slice_async_rq, 1, UINT_MAX, 0); STORE_FUNCTION(cfq_low_latency_store, &cfqd->cfq_latency, 0, 1, 0); -STORE_FUNCTION(cfq_group_isolation_store, &cfqd->cfq_group_isolation, 0, 1, 0); #undef STORE_FUNCTION #define CFQ_ATTR(name) \ @@ -4081,7 +4047,6 @@ static struct elv_fs_entry cfq_attrs[] = { CFQ_ATTR(slice_idle), CFQ_ATTR(group_idle), CFQ_ATTR(low_latency), - CFQ_ATTR(group_isolation), __ATTR_NULL }; |