2010-04-09 03:18:44

by Divyesh Shah

[permalink] [raw]
Subject: [PATCH] blkio: Changes to IO controller additional stats patches

that include some minor fixes and addresses all comments.

Changelog: (most based on Vivek Goyal's comments)
o renamed blkiocg_reset_write to blkiocg_reset_stats
o more clarification in the documentation on io_service_time and io_wait_time
o Initialize blkg->stats_lock
o rename io_add_stat to blkio_add_stat and declare it static
o use bool for direction and sync
o derive direction and sync info from existing rq methods
o use 12 for major:minor string length
o define io_service_time better to cover the NCQ case
o add a separate reset_stats interface
o make the indexed stats a 2d array to simplify macro and function pointer code
o blkio.time now exports in jiffies as before
o Added stats description in patch description and
Documentation/cgroup/blkio-controller.txt
o Prefix all stats functions with blkio and make them static as applicable
o replace IO_TYPE_MAX with IO_TYPE_TOTAL
o Moved #define constant to top of blk-cgroup.c
o Pass dev_t around instead of char *
o Add note to documentation file about resetting stats
o use BLK_CGROUP_MODULE in addition to BLK_CGROUP config option in #ifdef
statements
o Avoid struct request specific knowledge in blk-cgroup. blk-cgroup.h now has
rq_direction() and rq_sync() functions which are used by CFQ and when using
io-controller at a higher level, bio_* functions can be added.

Signed-off-by: Divyesh Shah<[email protected]>
---

block/blk-cgroup.c | 190 ++++++++++++++++++++++--------------------------
block/blk-cgroup.h | 64 ++++++++++------
block/cfq-iosched.c | 8 ++
include/linux/blkdev.h | 18 +++++
4 files changed, 151 insertions(+), 129 deletions(-)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 9af7257..6797df5 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -18,6 +18,8 @@
#include <linux/blkdev.h>
#include "blk-cgroup.h"

+#define MAX_KEY_LEN 100
+
static DEFINE_SPINLOCK(blkio_list_lock);
static LIST_HEAD(blkio_list);

@@ -56,24 +58,27 @@ struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
}
EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);

+void blkio_group_init(struct blkio_group *blkg)
+{
+ spin_lock_init(&blkg->stats_lock);
+}
+EXPORT_SYMBOL_GPL(blkio_group_init);
+
/*
* 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, unsigned int flags)
+static void blkio_add_stat(uint64_t *stat, uint64_t add, bool direction,
+ bool sync)
{
- if (flags & REQ_RW)
- stat[IO_WRITE] += add;
+ if (direction)
+ stat[BLKIO_STAT_WRITE] += add;
else
- stat[IO_READ] += add;
- /*
- * Everywhere in the block layer, an IO is treated as sync if it is a
- * read or a SYNC write. We follow the same norm.
- */
- if (!(flags & REQ_RW) || flags & REQ_RW_SYNC)
- stat[IO_SYNC] += add;
+ stat[BLKIO_STAT_READ] += add;
+ if (sync)
+ stat[BLKIO_STAT_SYNC] += add;
else
- stat[IO_ASYNC] += add;
+ stat[BLKIO_STAT_ASYNC] += add;
}

void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
@@ -86,23 +91,25 @@ void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
}
EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used);

-void blkiocg_update_request_dispatch_stats(struct blkio_group *blkg,
- struct request *rq)
+void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
+ uint64_t bytes, bool direction, bool sync)
{
struct blkio_group_stats *stats;
unsigned long flags;

spin_lock_irqsave(&blkg->stats_lock, flags);
stats = &blkg->stats;
- stats->sectors += blk_rq_sectors(rq);
- io_add_stat(stats->io_serviced, 1, rq->cmd_flags);
- io_add_stat(stats->io_service_bytes, blk_rq_sectors(rq) << 9,
- rq->cmd_flags);
+ stats->sectors += bytes >> 9;
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICED], 1, direction,
+ sync);
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_BYTES], bytes,
+ direction, sync);
spin_unlock_irqrestore(&blkg->stats_lock, flags);
}
+EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats);

-void blkiocg_update_request_completion_stats(struct blkio_group *blkg,
- struct request *rq)
+void blkiocg_update_completion_stats(struct blkio_group *blkg,
+ uint64_t start_time, uint64_t io_start_time, bool direction, bool sync)
{
struct blkio_group_stats *stats;
unsigned long flags;
@@ -110,16 +117,15 @@ void blkiocg_update_request_completion_stats(struct blkio_group *blkg,

spin_lock_irqsave(&blkg->stats_lock, flags);
stats = &blkg->stats;
- if (time_after64(now, rq->io_start_time_ns))
- io_add_stat(stats->io_service_time, now - rq->io_start_time_ns,
- rq->cmd_flags);
- if (time_after64(rq->io_start_time_ns, rq->start_time_ns))
- io_add_stat(stats->io_wait_time,
- rq->io_start_time_ns - rq->start_time_ns,
- rq->cmd_flags);
+ if (time_after64(now, io_start_time))
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_TIME],
+ now - io_start_time, direction, sync);
+ if (time_after64(io_start_time, start_time))
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_WAIT_TIME],
+ io_start_time - start_time, direction, sync);
spin_unlock_irqrestore(&blkg->stats_lock, flags);
}
-EXPORT_SYMBOL_GPL(blkiocg_update_request_completion_stats);
+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)
@@ -230,7 +236,7 @@ blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
}

static int
-blkiocg_reset_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
+blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val)
{
struct blkio_cgroup *blkcg;
struct blkio_group *blkg;
@@ -249,29 +255,32 @@ blkiocg_reset_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
return 0;
}

-void get_key_name(int type, char *disk_id, char *str, int chars_left)
+static void blkio_get_key_name(enum stat_sub_type type, dev_t dev, char *str,
+ int chars_left, bool diskname_only)
{
- strlcpy(str, disk_id, chars_left);
+ snprintf(str, chars_left, "%d:%d", MAJOR(dev), MINOR(dev));
chars_left -= strlen(str);
if (chars_left <= 0) {
printk(KERN_WARNING
"Possibly incorrect cgroup stat display format");
return;
}
+ if (diskname_only)
+ return;
switch (type) {
- case IO_READ:
+ case BLKIO_STAT_READ:
strlcat(str, " Read", chars_left);
break;
- case IO_WRITE:
+ case BLKIO_STAT_WRITE:
strlcat(str, " Write", chars_left);
break;
- case IO_SYNC:
+ case BLKIO_STAT_SYNC:
strlcat(str, " Sync", chars_left);
break;
- case IO_ASYNC:
+ case BLKIO_STAT_ASYNC:
strlcat(str, " Async", chars_left);
break;
- case IO_TYPE_MAX:
+ case BLKIO_STAT_TOTAL:
strlcat(str, " Total", chars_left);
break;
default:
@@ -279,63 +288,47 @@ void get_key_name(int type, char *disk_id, char *str, int chars_left)
}
}

-typedef uint64_t (get_var) (struct blkio_group *, int);
+static uint64_t blkio_fill_stat(char *str, int chars_left, uint64_t val,
+ struct cgroup_map_cb *cb, dev_t dev)
+{
+ blkio_get_key_name(0, dev, str, chars_left, true);
+ cb->fill(cb, str, val);
+ return val;
+}

-#define MAX_KEY_LEN 100
-uint64_t get_typed_stat(struct blkio_group *blkg, struct cgroup_map_cb *cb,
- get_var *getvar, char *disk_id)
+/* This should be called with blkg->stats_lock held */
+static uint64_t blkio_get_stat(struct blkio_group *blkg,
+ struct cgroup_map_cb *cb, dev_t dev, enum stat_type type)
{
uint64_t disk_total;
char key_str[MAX_KEY_LEN];
- int type;
+ enum stat_sub_type sub_type;
+
+ if (type == BLKIO_STAT_TIME)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.time, cb, dev);
+ if (type == BLKIO_STAT_SECTORS)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.sectors, cb, dev);
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ if (type == BLKIO_STAT_DEQUEUE)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.dequeue, cb, dev);
+#endif

- for (type = 0; type < IO_TYPE_MAX; type++) {
- get_key_name(type, disk_id, key_str, MAX_KEY_LEN);
- cb->fill(cb, key_str, getvar(blkg, type));
+ for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL;
+ sub_type++) {
+ blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false);
+ cb->fill(cb, key_str, blkg->stats.stat_arr[type][sub_type]);
}
- disk_total = getvar(blkg, IO_READ) + getvar(blkg, IO_WRITE);
- get_key_name(IO_TYPE_MAX, disk_id, key_str, MAX_KEY_LEN);
+ disk_total = blkg->stats.stat_arr[type][BLKIO_STAT_READ] +
+ blkg->stats.stat_arr[type][BLKIO_STAT_WRITE];
+ blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false);
cb->fill(cb, key_str, disk_total);
return disk_total;
}

-uint64_t get_stat(struct blkio_group *blkg, struct cgroup_map_cb *cb,
- get_var *getvar, char *disk_id)
-{
- uint64_t var = getvar(blkg, 0);
- cb->fill(cb, disk_id, var);
- return var;
-}
-
-#define GET_STAT_INDEXED(__VAR) \
-uint64_t get_##__VAR##_stat(struct blkio_group *blkg, int type) \
-{ \
- return blkg->stats.__VAR[type]; \
-} \
-
-GET_STAT_INDEXED(io_service_bytes);
-GET_STAT_INDEXED(io_serviced);
-GET_STAT_INDEXED(io_service_time);
-GET_STAT_INDEXED(io_wait_time);
-#undef GET_STAT_INDEXED
-
-#define GET_STAT(__VAR, __CONV) \
-uint64_t get_##__VAR##_stat(struct blkio_group *blkg, int dummy) \
-{ \
- uint64_t data = blkg->stats.__VAR; \
- if (__CONV) \
- data = (uint64_t)jiffies_to_msecs(data) * NSEC_PER_MSEC;\
- return data; \
-}
-
-GET_STAT(time, 1);
-GET_STAT(sectors, 0);
-#ifdef CONFIG_DEBUG_BLK_CGROUP
-GET_STAT(dequeue, 0);
-#endif
-#undef GET_STAT
-
-#define SHOW_FUNCTION_PER_GROUP(__VAR, get_stats, getvar, show_total) \
+#define SHOW_FUNCTION_PER_GROUP(__VAR, type, show_total) \
static int blkiocg_##__VAR##_read(struct cgroup *cgroup, \
struct cftype *cftype, struct cgroup_map_cb *cb) \
{ \
@@ -343,7 +336,6 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup, \
struct blkio_group *blkg; \
struct hlist_node *n; \
uint64_t cgroup_total = 0; \
- char disk_id[10]; \
\
if (!cgroup_lock_live_group(cgroup)) \
return -ENODEV; \
@@ -353,10 +345,8 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup, \
hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {\
if (blkg->dev) { \
spin_lock_irq(&blkg->stats_lock); \
- snprintf(disk_id, 10, "%u:%u", MAJOR(blkg->dev),\
- MINOR(blkg->dev)); \
- cgroup_total += get_stats(blkg, cb, getvar, \
- disk_id); \
+ cgroup_total += blkio_get_stat(blkg, cb, \
+ blkg->dev, type); \
spin_unlock_irq(&blkg->stats_lock); \
} \
} \
@@ -367,16 +357,14 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup, \
return 0; \
}

-SHOW_FUNCTION_PER_GROUP(time, get_stat, get_time_stat, 0);
-SHOW_FUNCTION_PER_GROUP(sectors, get_stat, get_sectors_stat, 0);
-SHOW_FUNCTION_PER_GROUP(io_service_bytes, get_typed_stat,
- get_io_service_bytes_stat, 1);
-SHOW_FUNCTION_PER_GROUP(io_serviced, get_typed_stat, get_io_serviced_stat, 1);
-SHOW_FUNCTION_PER_GROUP(io_service_time, get_typed_stat,
- get_io_service_time_stat, 1);
-SHOW_FUNCTION_PER_GROUP(io_wait_time, get_typed_stat, get_io_wait_time_stat, 1);
+SHOW_FUNCTION_PER_GROUP(time, BLKIO_STAT_TIME, 0);
+SHOW_FUNCTION_PER_GROUP(sectors, BLKIO_STAT_SECTORS, 0);
+SHOW_FUNCTION_PER_GROUP(io_service_bytes, BLKIO_STAT_SERVICE_BYTES, 1);
+SHOW_FUNCTION_PER_GROUP(io_serviced, BLKIO_STAT_SERVICED, 1);
+SHOW_FUNCTION_PER_GROUP(io_service_time, BLKIO_STAT_SERVICE_TIME, 1);
+SHOW_FUNCTION_PER_GROUP(io_wait_time, BLKIO_STAT_WAIT_TIME, 1);
#ifdef CONFIG_DEBUG_BLK_CGROUP
-SHOW_FUNCTION_PER_GROUP(dequeue, get_stat, get_dequeue_stat, 0);
+SHOW_FUNCTION_PER_GROUP(dequeue, BLKIO_STAT_DEQUEUE, 0);
#endif
#undef SHOW_FUNCTION_PER_GROUP

@@ -398,32 +386,30 @@ struct cftype blkio_files[] = {
{
.name = "time",
.read_map = blkiocg_time_read,
- .write_u64 = blkiocg_reset_write,
},
{
.name = "sectors",
.read_map = blkiocg_sectors_read,
- .write_u64 = blkiocg_reset_write,
},
{
.name = "io_service_bytes",
.read_map = blkiocg_io_service_bytes_read,
- .write_u64 = blkiocg_reset_write,
},
{
.name = "io_serviced",
.read_map = blkiocg_io_serviced_read,
- .write_u64 = blkiocg_reset_write,
},
{
.name = "io_service_time",
.read_map = blkiocg_io_service_time_read,
- .write_u64 = blkiocg_reset_write,
},
{
.name = "io_wait_time",
.read_map = blkiocg_io_wait_time_read,
- .write_u64 = blkiocg_reset_write,
+ },
+ {
+ .name = "reset_stats",
+ .write_u64 = blkiocg_reset_stats,
},
#ifdef CONFIG_DEBUG_BLK_CGROUP
{
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 80010ef..b22e553 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -23,12 +23,31 @@ extern struct cgroup_subsys blkio_subsys;
#define blkio_subsys_id blkio_subsys.subsys_id
#endif

-enum io_type {
- IO_READ = 0,
- IO_WRITE,
- IO_SYNC,
- IO_ASYNC,
- IO_TYPE_MAX
+enum stat_type {
+ /* Total time spent (in ns) between request dispatch to the driver and
+ * request completion for IOs doen by this cgroup. This may not be
+ * accurate when NCQ is turned on. */
+ BLKIO_STAT_SERVICE_TIME = 0,
+ /* Total bytes transferred */
+ BLKIO_STAT_SERVICE_BYTES,
+ /* Total IOs serviced, post merge */
+ BLKIO_STAT_SERVICED,
+ /* Total time spent waiting in scheduler queue in ns */
+ BLKIO_STAT_WAIT_TIME,
+ /* All the single valued stats go below this */
+ BLKIO_STAT_TIME,
+ BLKIO_STAT_SECTORS,
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ BLKIO_STAT_DEQUEUE
+#endif
+};
+
+enum stat_sub_type {
+ BLKIO_STAT_READ = 0,
+ BLKIO_STAT_WRITE,
+ BLKIO_STAT_SYNC,
+ BLKIO_STAT_ASYNC,
+ BLKIO_STAT_TOTAL
};

struct blkio_cgroup {
@@ -42,13 +61,7 @@ struct blkio_group_stats {
/* total disk time and nr sectors dispatched by this group */
uint64_t time;
uint64_t sectors;
- /* Total disk time used by IOs in ns */
- uint64_t io_service_time[IO_TYPE_MAX];
- uint64_t io_service_bytes[IO_TYPE_MAX]; /* Total bytes transferred */
- /* Total IOs serviced, post merge */
- uint64_t io_serviced[IO_TYPE_MAX];
- /* Total time spent waiting in scheduler queue in ns */
- uint64_t io_wait_time[IO_TYPE_MAX];
+ uint64_t stat_arr[BLKIO_STAT_WAIT_TIME + 1][BLKIO_STAT_TOTAL];
#ifdef CONFIG_DEBUG_BLK_CGROUP
/* How many times this group has been removed from service tree */
unsigned long dequeue;
@@ -65,7 +78,7 @@ struct blkio_group {
char path[128];
#endif
/* The device MKDEV(major, minor), this group has been created for */
- dev_t dev;
+ dev_t dev;

/* Need to serialize the stats in the case of reset/update */
spinlock_t stats_lock;
@@ -128,21 +141,21 @@ extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
void *key);
+void blkio_group_init(struct blkio_group *blkg);
void blkiocg_update_timeslice_used(struct blkio_group *blkg,
unsigned long time);
-void blkiocg_update_request_dispatch_stats(struct blkio_group *blkg,
- struct request *rq);
-void blkiocg_update_request_completion_stats(struct blkio_group *blkg,
- struct request *rq);
+void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
+ bool direction, bool sync);
+void blkiocg_update_completion_stats(struct blkio_group *blkg,
+ uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
#else
struct cgroup;
static inline struct blkio_cgroup *
cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }

+static inline void blkio_group_init(struct blkio_group *blkg) {}
static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
- struct blkio_group *blkg, void *key, dev_t dev)
-{
-}
+ struct blkio_group *blkg, void *key, dev_t dev) {}

static inline int
blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
@@ -151,9 +164,10 @@ 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_request_dispatch_stats(
- struct blkio_group *blkg, struct request *rq) {}
-static inline void blkiocg_update_request_completion_stats(
- struct blkio_group *blkg, struct request *rq) {}
+static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
+ uint64_t bytes, bool direction, bool sync) {}
+static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
+ uint64_t start_time, uint64_t io_start_time, bool direction,
+ bool sync) {}
#endif
#endif /* _BLK_CGROUP_H */
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 42028e7..5617ae0 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -955,6 +955,7 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
for_each_cfqg_st(cfqg, i, j, st)
*st = CFQ_RB_ROOT;
RB_CLEAR_NODE(&cfqg->rb_node);
+ blkio_group_init(&cfqg->blkg);

/*
* Take the initial reference that will be released on destroy
@@ -1865,7 +1866,8 @@ 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_request_dispatch_stats(&cfqq->cfqg->blkg, rq);
+ blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq),
+ rq_data_dir(rq), rq_is_sync(rq));
}

/*
@@ -3286,7 +3288,9 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
WARN_ON(!cfqq->dispatched);
cfqd->rq_in_driver--;
cfqq->dispatched--;
- blkiocg_update_request_completion_stats(&cfqq->cfqg->blkg, rq);
+ blkiocg_update_completion_stats(&cfqq->cfqg->blkg, rq_start_time_ns(rq),
+ rq_io_start_time_ns(rq), rq_data_dir(rq),
+ rq_is_sync(rq));

cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index f3fff8b..d483c49 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1209,9 +1209,27 @@ 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) \


2010-04-09 03:26:19

by Divyesh Shah

[permalink] [raw]
Subject: Re: [PATCH] blkio: Changes to IO controller additional stats patches

I missed out the changes to Documentation/cgroup/blkio-controller.txt.
Please ignore this one. Sorry.

On Thu, Apr 8, 2010 at 8:18 PM, Divyesh Shah <[email protected]> wrote:
> that include some minor fixes and addresses all comments.
>
> Changelog: (most based on Vivek Goyal's comments)
> o renamed blkiocg_reset_write to blkiocg_reset_stats
> o more clarification in the documentation on io_service_time and io_wait_time
> o Initialize blkg->stats_lock
> o rename io_add_stat to blkio_add_stat and declare it static
> o use bool for direction and sync
> o derive direction and sync info from existing rq methods
> o use 12 for major:minor string length
> o define io_service_time better to cover the NCQ case
> o add a separate reset_stats interface
> o make the indexed stats a 2d array to simplify macro and function pointer code
> o blkio.time now exports in jiffies as before
> o Added stats description in patch description and
> ?Documentation/cgroup/blkio-controller.txt
> o Prefix all stats functions with blkio and make them static as applicable
> o replace IO_TYPE_MAX with IO_TYPE_TOTAL
> o Moved #define constant to top of blk-cgroup.c
> o Pass dev_t around instead of char *
> o Add note to documentation file about resetting stats
> o use BLK_CGROUP_MODULE in addition to BLK_CGROUP config option in #ifdef
> ?statements
> o Avoid struct request specific knowledge in blk-cgroup. blk-cgroup.h now has
> ?rq_direction() and rq_sync() functions which are used by CFQ and when using
> ?io-controller at a higher level, bio_* functions can be added.
>
> Signed-off-by: Divyesh Shah<[email protected]>
> ---
>
> ?block/blk-cgroup.c ? ? | ?190 ++++++++++++++++++++++--------------------------
> ?block/blk-cgroup.h ? ? | ? 64 ++++++++++------
> ?block/cfq-iosched.c ? ?| ? ?8 ++
> ?include/linux/blkdev.h | ? 18 +++++
> ?4 files changed, 151 insertions(+), 129 deletions(-)
>
> diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
> index 9af7257..6797df5 100644
> --- a/block/blk-cgroup.c
> +++ b/block/blk-cgroup.c
> @@ -18,6 +18,8 @@
> ?#include <linux/blkdev.h>
> ?#include "blk-cgroup.h"
>
> +#define MAX_KEY_LEN 100
> +
> ?static DEFINE_SPINLOCK(blkio_list_lock);
> ?static LIST_HEAD(blkio_list);
>
> @@ -56,24 +58,27 @@ struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
> ?}
> ?EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);
>
> +void blkio_group_init(struct blkio_group *blkg)
> +{
> + ? ? ? spin_lock_init(&blkg->stats_lock);
> +}
> +EXPORT_SYMBOL_GPL(blkio_group_init);
> +
> ?/*
> ?* 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, unsigned int flags)
> +static void blkio_add_stat(uint64_t *stat, uint64_t add, bool direction,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? bool sync)
> ?{
> - ? ? ? if (flags & REQ_RW)
> - ? ? ? ? ? ? ? stat[IO_WRITE] += add;
> + ? ? ? if (direction)
> + ? ? ? ? ? ? ? stat[BLKIO_STAT_WRITE] += add;
> ? ? ? ?else
> - ? ? ? ? ? ? ? stat[IO_READ] += add;
> - ? ? ? /*
> - ? ? ? ?* Everywhere in the block layer, an IO is treated as sync if it is a
> - ? ? ? ?* read or a SYNC write. We follow the same norm.
> - ? ? ? ?*/
> - ? ? ? if (!(flags & REQ_RW) || flags & REQ_RW_SYNC)
> - ? ? ? ? ? ? ? stat[IO_SYNC] += add;
> + ? ? ? ? ? ? ? stat[BLKIO_STAT_READ] += add;
> + ? ? ? if (sync)
> + ? ? ? ? ? ? ? stat[BLKIO_STAT_SYNC] += add;
> ? ? ? ?else
> - ? ? ? ? ? ? ? stat[IO_ASYNC] += add;
> + ? ? ? ? ? ? ? stat[BLKIO_STAT_ASYNC] += add;
> ?}
>
> ?void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
> @@ -86,23 +91,25 @@ void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
> ?}
> ?EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used);
>
> -void blkiocg_update_request_dispatch_stats(struct blkio_group *blkg,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct request *rq)
> +void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? uint64_t bytes, bool direction, bool sync)
> ?{
> ? ? ? ?struct blkio_group_stats *stats;
> ? ? ? ?unsigned long flags;
>
> ? ? ? ?spin_lock_irqsave(&blkg->stats_lock, flags);
> ? ? ? ?stats = &blkg->stats;
> - ? ? ? stats->sectors += blk_rq_sectors(rq);
> - ? ? ? io_add_stat(stats->io_serviced, 1, rq->cmd_flags);
> - ? ? ? io_add_stat(stats->io_service_bytes, blk_rq_sectors(rq) << 9,
> - ? ? ? ? ? ? ? ? ? ? ? rq->cmd_flags);
> + ? ? ? stats->sectors += bytes >> 9;
> + ? ? ? blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICED], 1, direction,
> + ? ? ? ? ? ? ? ? ? ? ? sync);
> + ? ? ? blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_BYTES], bytes,
> + ? ? ? ? ? ? ? ? ? ? ? direction, sync);
> ? ? ? ?spin_unlock_irqrestore(&blkg->stats_lock, flags);
> ?}
> +EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats);
>
> -void blkiocg_update_request_completion_stats(struct blkio_group *blkg,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct request *rq)
> +void blkiocg_update_completion_stats(struct blkio_group *blkg,
> + ? ? ? uint64_t start_time, uint64_t io_start_time, bool direction, bool sync)
> ?{
> ? ? ? ?struct blkio_group_stats *stats;
> ? ? ? ?unsigned long flags;
> @@ -110,16 +117,15 @@ void blkiocg_update_request_completion_stats(struct blkio_group *blkg,
>
> ? ? ? ?spin_lock_irqsave(&blkg->stats_lock, flags);
> ? ? ? ?stats = &blkg->stats;
> - ? ? ? if (time_after64(now, rq->io_start_time_ns))
> - ? ? ? ? ? ? ? io_add_stat(stats->io_service_time, now - rq->io_start_time_ns,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? rq->cmd_flags);
> - ? ? ? if (time_after64(rq->io_start_time_ns, rq->start_time_ns))
> - ? ? ? ? ? ? ? io_add_stat(stats->io_wait_time,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? rq->io_start_time_ns - rq->start_time_ns,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? rq->cmd_flags);
> + ? ? ? if (time_after64(now, io_start_time))
> + ? ? ? ? ? ? ? blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_TIME],
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? now - io_start_time, direction, sync);
> + ? ? ? if (time_after64(io_start_time, start_time))
> + ? ? ? ? ? ? ? blkio_add_stat(stats->stat_arr[BLKIO_STAT_WAIT_TIME],
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? io_start_time - start_time, direction, sync);
> ? ? ? ?spin_unlock_irqrestore(&blkg->stats_lock, flags);
> ?}
> -EXPORT_SYMBOL_GPL(blkiocg_update_request_completion_stats);
> +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)
> @@ -230,7 +236,7 @@ blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
> ?}
>
> ?static int
> -blkiocg_reset_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
> +blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val)
> ?{
> ? ? ? ?struct blkio_cgroup *blkcg;
> ? ? ? ?struct blkio_group *blkg;
> @@ -249,29 +255,32 @@ blkiocg_reset_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
> ? ? ? ?return 0;
> ?}
>
> -void get_key_name(int type, char *disk_id, char *str, int chars_left)
> +static void blkio_get_key_name(enum stat_sub_type type, dev_t dev, char *str,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? int chars_left, bool diskname_only)
> ?{
> - ? ? ? strlcpy(str, disk_id, chars_left);
> + ? ? ? snprintf(str, chars_left, "%d:%d", MAJOR(dev), MINOR(dev));
> ? ? ? ?chars_left -= strlen(str);
> ? ? ? ?if (chars_left <= 0) {
> ? ? ? ? ? ? ? ?printk(KERN_WARNING
> ? ? ? ? ? ? ? ? ? ? ? ?"Possibly incorrect cgroup stat display format");
> ? ? ? ? ? ? ? ?return;
> ? ? ? ?}
> + ? ? ? if (diskname_only)
> + ? ? ? ? ? ? ? return;
> ? ? ? ?switch (type) {
> - ? ? ? case IO_READ:
> + ? ? ? case BLKIO_STAT_READ:
> ? ? ? ? ? ? ? ?strlcat(str, " Read", chars_left);
> ? ? ? ? ? ? ? ?break;
> - ? ? ? case IO_WRITE:
> + ? ? ? case BLKIO_STAT_WRITE:
> ? ? ? ? ? ? ? ?strlcat(str, " Write", chars_left);
> ? ? ? ? ? ? ? ?break;
> - ? ? ? case IO_SYNC:
> + ? ? ? case BLKIO_STAT_SYNC:
> ? ? ? ? ? ? ? ?strlcat(str, " Sync", chars_left);
> ? ? ? ? ? ? ? ?break;
> - ? ? ? case IO_ASYNC:
> + ? ? ? case BLKIO_STAT_ASYNC:
> ? ? ? ? ? ? ? ?strlcat(str, " Async", chars_left);
> ? ? ? ? ? ? ? ?break;
> - ? ? ? case IO_TYPE_MAX:
> + ? ? ? case BLKIO_STAT_TOTAL:
> ? ? ? ? ? ? ? ?strlcat(str, " Total", chars_left);
> ? ? ? ? ? ? ? ?break;
> ? ? ? ?default:
> @@ -279,63 +288,47 @@ void get_key_name(int type, char *disk_id, char *str, int chars_left)
> ? ? ? ?}
> ?}
>
> -typedef uint64_t (get_var) (struct blkio_group *, int);
> +static uint64_t blkio_fill_stat(char *str, int chars_left, uint64_t val,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct cgroup_map_cb *cb, dev_t dev)
> +{
> + ? ? ? blkio_get_key_name(0, dev, str, chars_left, true);
> + ? ? ? cb->fill(cb, str, val);
> + ? ? ? return val;
> +}
>
> -#define MAX_KEY_LEN 100
> -uint64_t get_typed_stat(struct blkio_group *blkg, struct cgroup_map_cb *cb,
> - ? ? ? ? ? ? ? get_var *getvar, char *disk_id)
> +/* This should be called with blkg->stats_lock held */
> +static uint64_t blkio_get_stat(struct blkio_group *blkg,
> + ? ? ? ? ? ? ? struct cgroup_map_cb *cb, dev_t dev, enum stat_type type)
> ?{
> ? ? ? ?uint64_t disk_total;
> ? ? ? ?char key_str[MAX_KEY_LEN];
> - ? ? ? int type;
> + ? ? ? enum stat_sub_type sub_type;
> +
> + ? ? ? if (type == BLKIO_STAT_TIME)
> + ? ? ? ? ? ? ? return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? blkg->stats.time, cb, dev);
> + ? ? ? if (type == BLKIO_STAT_SECTORS)
> + ? ? ? ? ? ? ? return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? blkg->stats.sectors, cb, dev);
> +#ifdef CONFIG_DEBUG_BLK_CGROUP
> + ? ? ? if (type == BLKIO_STAT_DEQUEUE)
> + ? ? ? ? ? ? ? return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? blkg->stats.dequeue, cb, dev);
> +#endif
>
> - ? ? ? for (type = 0; type < IO_TYPE_MAX; type++) {
> - ? ? ? ? ? ? ? get_key_name(type, disk_id, key_str, MAX_KEY_LEN);
> - ? ? ? ? ? ? ? cb->fill(cb, key_str, getvar(blkg, type));
> + ? ? ? for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL;
> + ? ? ? ? ? ? ? ? ? ? ? sub_type++) {
> + ? ? ? ? ? ? ? blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false);
> + ? ? ? ? ? ? ? cb->fill(cb, key_str, blkg->stats.stat_arr[type][sub_type]);
> ? ? ? ?}
> - ? ? ? disk_total = getvar(blkg, IO_READ) + getvar(blkg, IO_WRITE);
> - ? ? ? get_key_name(IO_TYPE_MAX, disk_id, key_str, MAX_KEY_LEN);
> + ? ? ? disk_total = blkg->stats.stat_arr[type][BLKIO_STAT_READ] +
> + ? ? ? ? ? ? ? ? ? ? ? blkg->stats.stat_arr[type][BLKIO_STAT_WRITE];
> + ? ? ? blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false);
> ? ? ? ?cb->fill(cb, key_str, disk_total);
> ? ? ? ?return disk_total;
> ?}
>
> -uint64_t get_stat(struct blkio_group *blkg, struct cgroup_map_cb *cb,
> - ? ? ? ? ? ? ? get_var *getvar, char *disk_id)
> -{
> - ? ? ? uint64_t var = getvar(blkg, 0);
> - ? ? ? cb->fill(cb, disk_id, var);
> - ? ? ? return var;
> -}
> -
> -#define GET_STAT_INDEXED(__VAR) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> -uint64_t get_##__VAR##_stat(struct blkio_group *blkg, int type) ? ? ? ? ? ? ? ?\
> -{ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> - ? ? ? return blkg->stats.__VAR[type]; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> -} ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> -
> -GET_STAT_INDEXED(io_service_bytes);
> -GET_STAT_INDEXED(io_serviced);
> -GET_STAT_INDEXED(io_service_time);
> -GET_STAT_INDEXED(io_wait_time);
> -#undef GET_STAT_INDEXED
> -
> -#define GET_STAT(__VAR, __CONV) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> -uint64_t get_##__VAR##_stat(struct blkio_group *blkg, int dummy) ? ? ? \
> -{ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> - ? ? ? uint64_t data = blkg->stats.__VAR; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> - ? ? ? if (__CONV) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> - ? ? ? ? ? ? ? data = (uint64_t)jiffies_to_msecs(data) * NSEC_PER_MSEC;\
> - ? ? ? return data; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> -}
> -
> -GET_STAT(time, 1);
> -GET_STAT(sectors, 0);
> -#ifdef CONFIG_DEBUG_BLK_CGROUP
> -GET_STAT(dequeue, 0);
> -#endif
> -#undef GET_STAT
> -
> -#define SHOW_FUNCTION_PER_GROUP(__VAR, get_stats, getvar, show_total) ?\
> +#define SHOW_FUNCTION_PER_GROUP(__VAR, type, show_total) ? ? ? ? ? ? ? \
> ?static int blkiocg_##__VAR##_read(struct cgroup *cgroup, ? ? ? ? ? ? ? \
> ? ? ? ? ? ? ? ?struct cftype *cftype, struct cgroup_map_cb *cb) ? ? ? ?\
> ?{ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> @@ -343,7 +336,6 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup, ? ? ? ? ? ?\
> ? ? ? ?struct blkio_group *blkg; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> ? ? ? ?struct hlist_node *n; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> ? ? ? ?uint64_t cgroup_total = 0; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> - ? ? ? char disk_id[10]; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> ? ? ? ?if (!cgroup_lock_live_group(cgroup)) ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> ? ? ? ? ? ? ? ?return -ENODEV; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> @@ -353,10 +345,8 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup, ? ? ? ? ? \
> ? ? ? ?hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {\
> ? ? ? ? ? ? ? ?if (blkg->dev) { ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> ? ? ? ? ? ? ? ? ? ? ? ?spin_lock_irq(&blkg->stats_lock); ? ? ? ? ? ? ? \
> - ? ? ? ? ? ? ? ? ? ? ? snprintf(disk_id, 10, "%u:%u", MAJOR(blkg->dev),\
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? MINOR(blkg->dev)); ? ? ? ? ? ? ?\
> - ? ? ? ? ? ? ? ? ? ? ? cgroup_total += get_stats(blkg, cb, getvar, ? ? \
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? disk_id); ? ? ? ? ? ? ? \
> + ? ? ? ? ? ? ? ? ? ? ? cgroup_total += blkio_get_stat(blkg, cb, ? ? ? ?\
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? blkg->dev, type); ? ? ? \
> ? ? ? ? ? ? ? ? ? ? ? ?spin_unlock_irq(&blkg->stats_lock); ? ? ? ? ? ? \
> ? ? ? ? ? ? ? ?} ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> ? ? ? ?} ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> @@ -367,16 +357,14 @@ static int blkiocg_##__VAR##_read(struct cgroup *cgroup, ? ? ? ? ?\
> ? ? ? ?return 0; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? \
> ?}
>
> -SHOW_FUNCTION_PER_GROUP(time, get_stat, get_time_stat, 0);
> -SHOW_FUNCTION_PER_GROUP(sectors, get_stat, get_sectors_stat, 0);
> -SHOW_FUNCTION_PER_GROUP(io_service_bytes, get_typed_stat,
> - ? ? ? ? ? ? ? ? ? ? ? get_io_service_bytes_stat, 1);
> -SHOW_FUNCTION_PER_GROUP(io_serviced, get_typed_stat, get_io_serviced_stat, 1);
> -SHOW_FUNCTION_PER_GROUP(io_service_time, get_typed_stat,
> - ? ? ? ? ? ? ? ? ? ? ? get_io_service_time_stat, 1);
> -SHOW_FUNCTION_PER_GROUP(io_wait_time, get_typed_stat, get_io_wait_time_stat, 1);
> +SHOW_FUNCTION_PER_GROUP(time, BLKIO_STAT_TIME, 0);
> +SHOW_FUNCTION_PER_GROUP(sectors, BLKIO_STAT_SECTORS, 0);
> +SHOW_FUNCTION_PER_GROUP(io_service_bytes, BLKIO_STAT_SERVICE_BYTES, 1);
> +SHOW_FUNCTION_PER_GROUP(io_serviced, BLKIO_STAT_SERVICED, 1);
> +SHOW_FUNCTION_PER_GROUP(io_service_time, BLKIO_STAT_SERVICE_TIME, 1);
> +SHOW_FUNCTION_PER_GROUP(io_wait_time, BLKIO_STAT_WAIT_TIME, 1);
> ?#ifdef CONFIG_DEBUG_BLK_CGROUP
> -SHOW_FUNCTION_PER_GROUP(dequeue, get_stat, get_dequeue_stat, 0);
> +SHOW_FUNCTION_PER_GROUP(dequeue, BLKIO_STAT_DEQUEUE, 0);
> ?#endif
> ?#undef SHOW_FUNCTION_PER_GROUP
>
> @@ -398,32 +386,30 @@ struct cftype blkio_files[] = {
> ? ? ? ?{
> ? ? ? ? ? ? ? ?.name = "time",
> ? ? ? ? ? ? ? ?.read_map = blkiocg_time_read,
> - ? ? ? ? ? ? ? .write_u64 = blkiocg_reset_write,
> ? ? ? ?},
> ? ? ? ?{
> ? ? ? ? ? ? ? ?.name = "sectors",
> ? ? ? ? ? ? ? ?.read_map = blkiocg_sectors_read,
> - ? ? ? ? ? ? ? .write_u64 = blkiocg_reset_write,
> ? ? ? ?},
> ? ? ? ?{
> ? ? ? ? ? ? ? ?.name = "io_service_bytes",
> ? ? ? ? ? ? ? ?.read_map = blkiocg_io_service_bytes_read,
> - ? ? ? ? ? ? ? .write_u64 = blkiocg_reset_write,
> ? ? ? ?},
> ? ? ? ?{
> ? ? ? ? ? ? ? ?.name = "io_serviced",
> ? ? ? ? ? ? ? ?.read_map = blkiocg_io_serviced_read,
> - ? ? ? ? ? ? ? .write_u64 = blkiocg_reset_write,
> ? ? ? ?},
> ? ? ? ?{
> ? ? ? ? ? ? ? ?.name = "io_service_time",
> ? ? ? ? ? ? ? ?.read_map = blkiocg_io_service_time_read,
> - ? ? ? ? ? ? ? .write_u64 = blkiocg_reset_write,
> ? ? ? ?},
> ? ? ? ?{
> ? ? ? ? ? ? ? ?.name = "io_wait_time",
> ? ? ? ? ? ? ? ?.read_map = blkiocg_io_wait_time_read,
> - ? ? ? ? ? ? ? .write_u64 = blkiocg_reset_write,
> + ? ? ? },
> + ? ? ? {
> + ? ? ? ? ? ? ? .name = "reset_stats",
> + ? ? ? ? ? ? ? .write_u64 = blkiocg_reset_stats,
> ? ? ? ?},
> ?#ifdef CONFIG_DEBUG_BLK_CGROUP
> ? ? ? ?{
> diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
> index 80010ef..b22e553 100644
> --- a/block/blk-cgroup.h
> +++ b/block/blk-cgroup.h
> @@ -23,12 +23,31 @@ extern struct cgroup_subsys blkio_subsys;
> ?#define blkio_subsys_id blkio_subsys.subsys_id
> ?#endif
>
> -enum io_type {
> - ? ? ? IO_READ = 0,
> - ? ? ? IO_WRITE,
> - ? ? ? IO_SYNC,
> - ? ? ? IO_ASYNC,
> - ? ? ? IO_TYPE_MAX
> +enum stat_type {
> + ? ? ? /* Total time spent (in ns) between request dispatch to the driver and
> + ? ? ? ?* request completion for IOs doen by this cgroup. This may not be
> + ? ? ? ?* accurate when NCQ is turned on. */
> + ? ? ? BLKIO_STAT_SERVICE_TIME = 0,
> + ? ? ? /* Total bytes transferred */
> + ? ? ? BLKIO_STAT_SERVICE_BYTES,
> + ? ? ? /* Total IOs serviced, post merge */
> + ? ? ? BLKIO_STAT_SERVICED,
> + ? ? ? /* Total time spent waiting in scheduler queue in ns */
> + ? ? ? BLKIO_STAT_WAIT_TIME,
> + ? ? ? /* All the single valued stats go below this */
> + ? ? ? BLKIO_STAT_TIME,
> + ? ? ? BLKIO_STAT_SECTORS,
> +#ifdef CONFIG_DEBUG_BLK_CGROUP
> + ? ? ? BLKIO_STAT_DEQUEUE
> +#endif
> +};
> +
> +enum stat_sub_type {
> + ? ? ? BLKIO_STAT_READ = 0,
> + ? ? ? BLKIO_STAT_WRITE,
> + ? ? ? BLKIO_STAT_SYNC,
> + ? ? ? BLKIO_STAT_ASYNC,
> + ? ? ? BLKIO_STAT_TOTAL
> ?};
>
> ?struct blkio_cgroup {
> @@ -42,13 +61,7 @@ struct blkio_group_stats {
> ? ? ? ?/* total disk time and nr sectors dispatched by this group */
> ? ? ? ?uint64_t time;
> ? ? ? ?uint64_t sectors;
> - ? ? ? /* Total disk time used by IOs in ns */
> - ? ? ? uint64_t io_service_time[IO_TYPE_MAX];
> - ? ? ? uint64_t io_service_bytes[IO_TYPE_MAX]; /* Total bytes transferred */
> - ? ? ? /* Total IOs serviced, post merge */
> - ? ? ? uint64_t io_serviced[IO_TYPE_MAX];
> - ? ? ? /* Total time spent waiting in scheduler queue in ns */
> - ? ? ? uint64_t io_wait_time[IO_TYPE_MAX];
> + ? ? ? uint64_t stat_arr[BLKIO_STAT_WAIT_TIME + 1][BLKIO_STAT_TOTAL];
> ?#ifdef CONFIG_DEBUG_BLK_CGROUP
> ? ? ? ?/* How many times this group has been removed from service tree */
> ? ? ? ?unsigned long dequeue;
> @@ -65,7 +78,7 @@ struct blkio_group {
> ? ? ? ?char path[128];
> ?#endif
> ? ? ? ?/* The device MKDEV(major, minor), this group has been created for */
> - ? ? ? dev_t ? dev;
> + ? ? ? dev_t dev;
>
> ? ? ? ?/* Need to serialize the stats in the case of reset/update */
> ? ? ? ?spinlock_t stats_lock;
> @@ -128,21 +141,21 @@ extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
> ?extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
> ?extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?void *key);
> +void blkio_group_init(struct blkio_group *blkg);
> ?void blkiocg_update_timeslice_used(struct blkio_group *blkg,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?unsigned long time);
> -void blkiocg_update_request_dispatch_stats(struct blkio_group *blkg,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct request *rq);
> -void blkiocg_update_request_completion_stats(struct blkio_group *blkg,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct request *rq);
> +void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? bool direction, bool sync);
> +void blkiocg_update_completion_stats(struct blkio_group *blkg,
> + ? ? ? uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
> ?#else
> ?struct cgroup;
> ?static inline struct blkio_cgroup *
> ?cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
>
> +static inline void blkio_group_init(struct blkio_group *blkg) {}
> ?static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
> - ? ? ? ? ? ? ? ? ? ? ? struct blkio_group *blkg, void *key, dev_t dev)
> -{
> -}
> + ? ? ? ? ? ? ? ? ? ? ? struct blkio_group *blkg, void *key, dev_t dev) {}
>
> ?static inline int
> ?blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
> @@ -151,9 +164,10 @@ 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_request_dispatch_stats(
> - ? ? ? ? ? ? ? struct blkio_group *blkg, struct request *rq) {}
> -static inline void blkiocg_update_request_completion_stats(
> - ? ? ? ? ? ? ? struct blkio_group *blkg, struct request *rq) {}
> +static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? uint64_t bytes, bool direction, bool sync) {}
> +static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
> + ? ? ? ? ? ? ? uint64_t start_time, uint64_t io_start_time, bool direction,
> + ? ? ? ? ? ? ? bool sync) {}
> ?#endif
> ?#endif /* _BLK_CGROUP_H */
> diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
> index 42028e7..5617ae0 100644
> --- a/block/cfq-iosched.c
> +++ b/block/cfq-iosched.c
> @@ -955,6 +955,7 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
> ? ? ? ?for_each_cfqg_st(cfqg, i, j, st)
> ? ? ? ? ? ? ? ?*st = CFQ_RB_ROOT;
> ? ? ? ?RB_CLEAR_NODE(&cfqg->rb_node);
> + ? ? ? blkio_group_init(&cfqg->blkg);
>
> ? ? ? ?/*
> ? ? ? ? * Take the initial reference that will be released on destroy
> @@ -1865,7 +1866,8 @@ 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_request_dispatch_stats(&cfqq->cfqg->blkg, rq);
> + ? ? ? blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq),
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? rq_data_dir(rq), rq_is_sync(rq));
> ?}
>
> ?/*
> @@ -3286,7 +3288,9 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
> ? ? ? ?WARN_ON(!cfqq->dispatched);
> ? ? ? ?cfqd->rq_in_driver--;
> ? ? ? ?cfqq->dispatched--;
> - ? ? ? blkiocg_update_request_completion_stats(&cfqq->cfqg->blkg, rq);
> + ? ? ? blkiocg_update_completion_stats(&cfqq->cfqg->blkg, rq_start_time_ns(rq),
> + ? ? ? ? ? ? ? ? ? ? ? rq_io_start_time_ns(rq), rq_data_dir(rq),
> + ? ? ? ? ? ? ? ? ? ? ? rq_is_sync(rq));
>
> ? ? ? ?cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
>
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index f3fff8b..d483c49 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -1209,9 +1209,27 @@ 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) \
>
>