812df48d12
1) group_wait_time - This is the amount of time the cgroup had to wait to get a timeslice for one of its queues from when it became busy, i.e., went from 0 to 1 request queued. This is different from the io_wait_time which is the cumulative total of the amount of time spent by each IO in that cgroup waiting in the scheduler queue. This stat is a great way to find out any jobs in the fleet that are being starved or waiting for longer than what is expected (due to an IO controller bug or any other issue). 2) empty_time - This is the amount of time a cgroup spends w/o any pending requests. This stat is useful when a job does not seem to be able to use its assigned disk share by helping check if that is happening due to an IO controller bug or because the job is not submitting enough IOs. 3) idle_time - This is the amount of time spent by the IO scheduler idling for a given cgroup in anticipation of a better request than the exising ones from other queues/cgroups. All these stats are recorded using start and stop events. When reading these stats, we do not add the delta between the current time and the last start time if we're between the start and stop events. We avoid doing this to make sure that these numbers are always monotonically increasing when read. Since we're using sched_clock() which may use the tsc as its source, it may induce some inconsistency (due to tsc resync across cpus) if we included the current delta. Signed-off-by: Divyesh Shah<dpshah@google.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
252 lines
7.9 KiB
C
252 lines
7.9 KiB
C
#ifndef _BLK_CGROUP_H
|
|
#define _BLK_CGROUP_H
|
|
/*
|
|
* Common Block IO controller cgroup interface
|
|
*
|
|
* Based on ideas and code from CFQ, CFS and BFQ:
|
|
* Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
|
|
*
|
|
* Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it>
|
|
* Paolo Valente <paolo.valente@unimore.it>
|
|
*
|
|
* Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com>
|
|
* Nauman Rafique <nauman@google.com>
|
|
*/
|
|
|
|
#include <linux/cgroup.h>
|
|
|
|
#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
|
|
|
|
#ifndef CONFIG_BLK_CGROUP
|
|
/* When blk-cgroup is a module, its subsys_id isn't a compile-time constant */
|
|
extern struct cgroup_subsys blkio_subsys;
|
|
#define blkio_subsys_id blkio_subsys.subsys_id
|
|
#endif
|
|
|
|
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,
|
|
/* Number of IOs merged */
|
|
BLKIO_STAT_MERGED,
|
|
/* Number of IOs queued up */
|
|
BLKIO_STAT_QUEUED,
|
|
/* All the single valued stats go below this */
|
|
BLKIO_STAT_TIME,
|
|
BLKIO_STAT_SECTORS,
|
|
#ifdef CONFIG_DEBUG_BLK_CGROUP
|
|
BLKIO_STAT_AVG_QUEUE_SIZE,
|
|
BLKIO_STAT_IDLE_TIME,
|
|
BLKIO_STAT_EMPTY_TIME,
|
|
BLKIO_STAT_GROUP_WAIT_TIME,
|
|
BLKIO_STAT_DEQUEUE
|
|
#endif
|
|
};
|
|
|
|
enum stat_sub_type {
|
|
BLKIO_STAT_READ = 0,
|
|
BLKIO_STAT_WRITE,
|
|
BLKIO_STAT_SYNC,
|
|
BLKIO_STAT_ASYNC,
|
|
BLKIO_STAT_TOTAL
|
|
};
|
|
|
|
/* blkg state flags */
|
|
enum blkg_state_flags {
|
|
BLKG_waiting = 0,
|
|
BLKG_idling,
|
|
BLKG_empty,
|
|
};
|
|
|
|
struct blkio_cgroup {
|
|
struct cgroup_subsys_state css;
|
|
unsigned int weight;
|
|
spinlock_t lock;
|
|
struct hlist_head blkg_list;
|
|
};
|
|
|
|
struct blkio_group_stats {
|
|
/* total disk time and nr sectors dispatched by this group */
|
|
uint64_t time;
|
|
uint64_t sectors;
|
|
uint64_t stat_arr[BLKIO_STAT_QUEUED + 1][BLKIO_STAT_TOTAL];
|
|
#ifdef CONFIG_DEBUG_BLK_CGROUP
|
|
/* Sum of number of IOs queued across all samples */
|
|
uint64_t avg_queue_size_sum;
|
|
/* Count of samples taken for average */
|
|
uint64_t avg_queue_size_samples;
|
|
/* How many times this group has been removed from service tree */
|
|
unsigned long dequeue;
|
|
|
|
/* Total time spent waiting for it to be assigned a timeslice. */
|
|
uint64_t group_wait_time;
|
|
uint64_t start_group_wait_time;
|
|
|
|
/* Time spent idling for this blkio_group */
|
|
uint64_t idle_time;
|
|
uint64_t start_idle_time;
|
|
/*
|
|
* Total time when we have requests queued and do not contain the
|
|
* current active queue.
|
|
*/
|
|
uint64_t empty_time;
|
|
uint64_t start_empty_time;
|
|
uint16_t flags;
|
|
#endif
|
|
};
|
|
|
|
struct blkio_group {
|
|
/* An rcu protected unique identifier for the group */
|
|
void *key;
|
|
struct hlist_node blkcg_node;
|
|
unsigned short blkcg_id;
|
|
#ifdef CONFIG_DEBUG_BLK_CGROUP
|
|
/* Store cgroup path */
|
|
char path[128];
|
|
#endif
|
|
/* The device MKDEV(major, minor), this group has been created for */
|
|
dev_t dev;
|
|
|
|
/* Need to serialize the stats in the case of reset/update */
|
|
spinlock_t stats_lock;
|
|
struct blkio_group_stats stats;
|
|
};
|
|
|
|
typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg);
|
|
typedef void (blkio_update_group_weight_fn) (struct blkio_group *blkg,
|
|
unsigned int weight);
|
|
|
|
struct blkio_policy_ops {
|
|
blkio_unlink_group_fn *blkio_unlink_group_fn;
|
|
blkio_update_group_weight_fn *blkio_update_group_weight_fn;
|
|
};
|
|
|
|
struct blkio_policy_type {
|
|
struct list_head list;
|
|
struct blkio_policy_ops ops;
|
|
};
|
|
|
|
/* Blkio controller policy registration */
|
|
extern void blkio_policy_register(struct blkio_policy_type *);
|
|
extern void blkio_policy_unregister(struct blkio_policy_type *);
|
|
|
|
#else
|
|
|
|
struct blkio_group {
|
|
};
|
|
|
|
struct blkio_policy_type {
|
|
};
|
|
|
|
static inline void blkio_policy_register(struct blkio_policy_type *blkiop) { }
|
|
static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
|
|
|
|
#endif
|
|
|
|
#define BLKIO_WEIGHT_MIN 100
|
|
#define BLKIO_WEIGHT_MAX 1000
|
|
#define BLKIO_WEIGHT_DEFAULT 500
|
|
|
|
#ifdef CONFIG_DEBUG_BLK_CGROUP
|
|
static inline char *blkg_path(struct blkio_group *blkg)
|
|
{
|
|
return blkg->path;
|
|
}
|
|
void blkiocg_update_set_active_queue_stats(struct blkio_group *blkg);
|
|
void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
|
|
unsigned long dequeue);
|
|
void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg);
|
|
void blkiocg_update_idle_time_stats(struct blkio_group *blkg);
|
|
void blkiocg_set_start_empty_time(struct blkio_group *blkg, bool ignore);
|
|
|
|
#define BLKG_FLAG_FNS(name) \
|
|
static inline void blkio_mark_blkg_##name( \
|
|
struct blkio_group_stats *stats) \
|
|
{ \
|
|
stats->flags |= (1 << BLKG_##name); \
|
|
} \
|
|
static inline void blkio_clear_blkg_##name( \
|
|
struct blkio_group_stats *stats) \
|
|
{ \
|
|
stats->flags &= ~(1 << BLKG_##name); \
|
|
} \
|
|
static inline int blkio_blkg_##name(struct blkio_group_stats *stats) \
|
|
{ \
|
|
return (stats->flags & (1 << BLKG_##name)) != 0; \
|
|
} \
|
|
|
|
BLKG_FLAG_FNS(waiting)
|
|
BLKG_FLAG_FNS(idling)
|
|
BLKG_FLAG_FNS(empty)
|
|
#undef BLKG_FLAG_FNS
|
|
#else
|
|
static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
|
|
static inline void blkiocg_update_set_active_queue_stats(
|
|
struct blkio_group *blkg) {}
|
|
static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
|
|
unsigned long dequeue) {}
|
|
static inline void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg)
|
|
{}
|
|
static inline void blkiocg_update_idle_time_stats(struct blkio_group *blkg) {}
|
|
static inline void blkiocg_set_start_empty_time(struct blkio_group *blkg,
|
|
bool ignore) {}
|
|
#endif
|
|
|
|
#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
|
|
extern struct blkio_cgroup blkio_root_cgroup;
|
|
extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
|
|
extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
|
|
struct blkio_group *blkg, void *key, dev_t dev);
|
|
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_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);
|
|
void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
|
|
bool sync);
|
|
void blkiocg_update_request_add_stats(struct blkio_group *blkg,
|
|
struct blkio_group *curr_blkg, bool direction, bool sync);
|
|
void blkiocg_update_request_remove_stats(struct blkio_group *blkg,
|
|
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) {}
|
|
|
|
static inline int
|
|
blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
|
|
|
|
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, 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) {}
|
|
static inline void blkiocg_update_io_merged_stats(struct blkio_group *blkg,
|
|
bool direction, bool sync) {}
|
|
static inline void blkiocg_update_request_add_stats(struct blkio_group *blkg,
|
|
struct blkio_group *curr_blkg, bool direction, bool sync) {}
|
|
static inline void blkiocg_update_request_remove_stats(struct blkio_group *blkg,
|
|
bool direction, bool sync) {}
|
|
#endif
|
|
#endif /* _BLK_CGROUP_H */
|