[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <n2xaf41c7c41004051510ne0be83n4ce58e22d6ef64f7@mail.gmail.com>
Date: Mon, 5 Apr 2010 15:10:44 -0700
From: Divyesh Shah <dpshah@...gle.com>
To: Vivek Goyal <vgoyal@...hat.com>
Cc: jens.axboe@...cle.com, linux-kernel@...r.kernel.org,
nauman@...gle.com, ctalbott@...gle.com
Subject: Re: [PATCH 3/3][v2] blkio: Increment the blkio cgroup stats for real
now
On Mon, Apr 5, 2010 at 11:12 AM, Vivek Goyal <vgoyal@...hat.com> wrote:
> On Fri, Apr 02, 2010 at 06:57:27PM -0700, Divyesh Shah wrote:
>> We also add start_time_ns and io_start_time_ns fields to struct request
>> here to record the time when a request is created and when it is
>> dispatched to device. We use ns uints here as ms and jiffies are
>> not very useful for non-rotational media.
>>
>> Signed-off-by: Divyesh Shah<dpshah@...gle.com>
>> ---
>>
>> block/blk-cgroup.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++--
>> block/blk-cgroup.h | 33 +++++++++++++++++++++++++++++---
>> block/blk-core.c | 6 ++++--
>> block/cfq-iosched.c | 6 +++++-
>> include/linux/blkdev.h | 38 ++++++++++++++++++++++++++++++++++++-
>> 5 files changed, 123 insertions(+), 9 deletions(-)
>>
>> diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
>> index cac10b2..21c0d28 100644
>> --- a/block/blk-cgroup.c
>> +++ b/block/blk-cgroup.c
>> @@ -15,6 +15,7 @@
>> #include <linux/kdev_t.h>
>> #include <linux/module.h>
>> #include <linux/err.h>
>> +#include <linux/blkdev.h>
>> #include "blk-cgroup.h"
>>
>> #define MAX_KEY_LEN 100
>> @@ -57,6 +58,16 @@ struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
>> }
>> EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);
>>
>> +/*
>> + * Add to the appropriate stat variable depending on the request type.
>> + * This should be called with the blkg->stats_lock held.
>> + */
>> +void io_add_stat(uint64_t *stat, uint64_t add, int direction, int sync)
>> +{
>> + stat[direction] += add;
>> + stat[sync] += add;
>> +}
>> +
>
> static? blkio_add_stat()?
Will fix in V3
>
> how about using "bool" for direction and sync? This is true throughout the
> patch.
Will do.
>
>> void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
>> {
>> unsigned long flags;
>> @@ -67,6 +78,40 @@ void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
>> }
>> EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used);
>>
>> +void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
>> + uint64_t bytes, int direction, int sync)
>> +{
>> + struct blkio_group_stats *stats;
>> + unsigned long flags;
>> +
>> + spin_lock_irqsave(&blkg->stats_lock, flags);
>> + stats = &blkg->stats;
>> + stats->sectors += bytes >> 9;
>> + io_add_stat(stats->io_serviced, 1, direction, sync);
>> + io_add_stat(stats->io_service_bytes, bytes, direction, sync);
>> + spin_unlock_irqrestore(&blkg->stats_lock, flags);
>> +}
>> +EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats);
>> +
>> +void blkiocg_update_completion_stats(struct blkio_group *blkg,
>> + uint64_t start_time, uint64_t io_start_time, int direction, int sync)
>> +{
>> + struct blkio_group_stats *stats;
>> + unsigned long flags;
>> + unsigned long long now = sched_clock();
>> +
>> + spin_lock_irqsave(&blkg->stats_lock, flags);
>> + stats = &blkg->stats;
>> + if (time_after64(now, io_start_time))
>> + io_add_stat(stats->io_service_time, now - io_start_time,
>> + direction, sync);
>> + if (time_after64(io_start_time, start_time))
>> + io_add_stat(stats->io_wait_time, io_start_time - start_time,
>> + direction, sync);
>> + spin_unlock_irqrestore(&blkg->stats_lock, flags);
>> +}
>> +EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats);
>> +
>> void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
>> struct blkio_group *blkg, void *key, dev_t dev)
>> {
>> @@ -325,12 +370,12 @@ SHOW_FUNCTION_PER_GROUP(dequeue, blkio_get_stat, blkio_get_dequeue_stat, 0);
>> #undef SHOW_FUNCTION_PER_GROUP
>>
>> #ifdef CONFIG_DEBUG_BLK_CGROUP
>> -void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
>> +void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
>> unsigned long dequeue)
>> {
>> blkg->stats.dequeue += dequeue;
>> }
>> -EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_dequeue_stats);
>> +EXPORT_SYMBOL_GPL(blkiocg_update_dequeue_stats);
>> #endif
>>
>> struct cftype blkio_files[] = {
>> diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
>> index e8600b0..5fc88e1 100644
>> --- a/block/blk-cgroup.h
>> +++ b/block/blk-cgroup.h
>> @@ -112,12 +112,12 @@ static inline char *blkg_path(struct blkio_group *blkg)
>> {
>> return blkg->path;
>> }
>> -void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
>> +void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
>> unsigned long dequeue);
>> #else
>> static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
>> -static inline void blkiocg_update_blkio_group_dequeue_stats(
>> - struct blkio_group *blkg, unsigned long dequeue) {}
>> +static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
>> + unsigned long dequeue) {}
>> #endif
>>
>> #if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
>> @@ -130,6 +130,20 @@ extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
>> void *key);
>> void blkiocg_update_timeslice_used(struct blkio_group *blkg,
>> unsigned long time);
>> +void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
>> + int direction, int sync);
>> +void blkiocg_update_completion_stats(struct blkio_group *blkg,
>> + uint64_t start_time, uint64_t io_start_time, int direction, int sync);
>> +static inline int rq_direction(struct request *rq)
>> +{
>> + return (rq->cmd_flags & REQ_RW) ? IO_WRITE : IO_READ;
>> +}
>
> blkdev.h offers rq_data_dir(). Let mapping of 0 or 1 to correct enum
> happen in blkio-cgroup.c. This is not rq property. This is internal to
> blkio.
Will fix in v3 for both direction and sync mapping.
>
>> +
>> +static inline int rq_sync(struct request *rq)
>> +{
>> + return (!(rq->cmd_flags & REQ_RW) ||
>> + rq->cmd_flags & REQ_RW_SYNC) ? IO_SYNC : IO_ASYNC;
>> +}
>
>
> blkdev.h already offers rq_is_sync(). We can use that. Mapping of 1 or 0
> to corrent enum number IO_SYNC, IO_ASYNC can be done by blkio-cgroup.c
>
>
> Vivek
>
>> #else
>> struct cgroup;
>> static inline struct blkio_cgroup *
>> @@ -147,5 +161,18 @@ static inline struct blkio_group *
>> blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; }
>> static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg,
>> unsigned long time) {}
>> +static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
>> + uint64_t bytes, int direction, int sync) {}
>> +static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
>> + uint64_t start_time, uint64_t io_start_time, int direction, int sync) {}
>> +static inline int rq_direction(struct request *rq)
>> +{
>> + return 0;
>> +}
>> +
>> +static inline int rq_sync(struct request *rq)
>> +{
>> + return 0;
>> +}
>> #endif
>> #endif /* _BLK_CGROUP_H */
>> diff --git a/block/blk-core.c b/block/blk-core.c
>> index 9fe174d..1d94f15 100644
>> --- a/block/blk-core.c
>> +++ b/block/blk-core.c
>> @@ -127,6 +127,7 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
>> rq->tag = -1;
>> rq->ref_count = 1;
>> rq->start_time = jiffies;
>> + set_start_time_ns(rq);
>> }
>> EXPORT_SYMBOL(blk_rq_init);
>>
>> @@ -1855,8 +1856,10 @@ void blk_dequeue_request(struct request *rq)
>> * and to it is freed is accounted as io that is in progress at
>> * the driver side.
>> */
>> - if (blk_account_rq(rq))
>> + if (blk_account_rq(rq)) {
>> q->in_flight[rq_is_sync(rq)]++;
>> + set_io_start_time_ns(rq);
>> + }
>> }
>>
>> /**
>> @@ -2517,4 +2520,3 @@ int __init blk_dev_init(void)
>>
>> return 0;
>> }
>> -
>> diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
>> index d91df9f..59aeadf 100644
>> --- a/block/cfq-iosched.c
>> +++ b/block/cfq-iosched.c
>> @@ -854,7 +854,7 @@ cfq_group_service_tree_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
>> if (!RB_EMPTY_NODE(&cfqg->rb_node))
>> cfq_rb_erase(&cfqg->rb_node, st);
>> cfqg->saved_workload_slice = 0;
>> - blkiocg_update_blkio_group_dequeue_stats(&cfqg->blkg, 1);
>> + blkiocg_update_dequeue_stats(&cfqg->blkg, 1);
>> }
>>
>> static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq)
>> @@ -1864,6 +1864,8 @@ static void cfq_dispatch_insert(struct request_queue *q, struct request *rq)
>> elv_dispatch_sort(q, rq);
>>
>> cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++;
>> + blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq),
>> + rq_direction(rq), rq_sync(rq));
>> }
>>
>> /*
>> @@ -3284,6 +3286,8 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
>> WARN_ON(!cfqq->dispatched);
>> cfqd->rq_in_driver--;
>> cfqq->dispatched--;
>> + blkiocg_update_completion_stats(&cfqq->cfqg->blkg, rq_start_time_ns(rq),
>> + rq_io_start_time_ns(rq), rq_direction(rq), rq_sync(rq));
>>
>> cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
>>
>> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
>> index ebd22db..ac1f30d 100644
>> --- a/include/linux/blkdev.h
>> +++ b/include/linux/blkdev.h
>> @@ -193,7 +193,10 @@ struct request {
>>
>> struct gendisk *rq_disk;
>> unsigned long start_time;
>> -
>> +#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
>> + unsigned long long start_time_ns;
>> + unsigned long long io_start_time_ns; /* when passed to hardware */
>> +#endif
>> /* Number of scatter-gather DMA addr+len pairs after
>> * physical address coalescing is performed.
>> */
>> @@ -1219,6 +1222,39 @@ static inline void put_dev_sector(Sector p)
>> struct work_struct;
>> int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
>>
>> +#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
>> +static inline void set_start_time_ns(struct request *req)
>> +{
>> + req->start_time_ns = sched_clock();
>> +}
>> +
>> +static inline void set_io_start_time_ns(struct request *req)
>> +{
>> + req->io_start_time_ns = sched_clock();
>> +}
>> +
>> +static inline uint64_t rq_start_time_ns(struct request *req)
>> +{
>> + return req->start_time_ns;
>> +}
>> +
>> +static inline uint64_t rq_io_start_time_ns(struct request *req)
>> +{
>> + return req->io_start_time_ns;
>> +}
>> +#else
>> +static inline void set_start_time_ns(struct request *req) {}
>> +static inline void set_io_start_time_ns(struct request *req) {}
>> +static inline uint64_t rq_start_time_ns(struct request *req)
>> +{
>> + return 0;
>> +}
>> +static inline uint64_t rq_io_start_time_ns(struct request *req)
>> +{
>> + return 0;
>> +}
>> +#endif
>> +
>> #define MODULE_ALIAS_BLOCKDEV(major,minor) \
>> MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
>> #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists