block: Add Maple I/O Scheduler

Adapted to State Notifier by @farovitus

Signed-off-by: djb77 <dwayne.bakewell@gmail.com>
Signed-off-by: prashantpaddune <elonpras@my.smccd.edu>
This commit is contained in:
Joe Maples 2017-06-30 16:35:23 -07:00 committed by prashantpaddune
parent de23aa06ae
commit 12c22648f0
4 changed files with 435 additions and 0 deletions

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@ -315,6 +315,7 @@ CONFIG_IOSCHED_SIOPLUS=y
CONFIG_IOSCHED_TRIPNDROID=y
CONFIG_IOSCHED_VR=y
CONFIG_IOSCHED_ZEN=y
CONFIG_IOSCHED_MAPLE=y
CONFIG_DEFAULT_CFQ=y
# CONFIG_DEFAULT_BFQ is not set
# CONFIG_DEFAULT_NOOP is not set
@ -325,6 +326,7 @@ CONFIG_DEFAULT_CFQ=y
# CONFIG_DEFAULT_TRIPNDROID is not set
# CONFIG_DEFAULT_VR is not set
# CONFIG_DEFAULT_ZEN is not set
# CONFIG_DEFAULT_MAPLE is not set
CONFIG_DEFAULT_IOSCHED="cfq"
CONFIG_ASN1=y
CONFIG_UNINLINE_SPIN_UNLOCK=y

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@ -21,6 +21,10 @@ config IOSCHED_DEADLINE
a new point in the service tree and doing a batch of IO from there
in case of expiry.
config IOSCHED_MAPLE
tristate "Maple I/O scheduler"
default y
config IOSCHED_CFQ
tristate "CFQ I/O scheduler"
default y
@ -160,6 +164,9 @@ choice
config DEFAULT_ZEN
bool "ZEN" if IOSCHED_ZEN=y
config DEFAULT_MAPLE
bool "Maple" if IOSCHED_MAPLE=y
endchoice
config DEFAULT_IOSCHED
@ -175,6 +182,7 @@ config DEFAULT_IOSCHED
default "tripndroid" if DEFAULT_TRIPNDROID
default "vr" if DEFAULT_VR
default "zen" if DEFAULT_ZEN
default "maple" if DEFAULT_MAPLE
endmenu

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@ -26,6 +26,7 @@ obj-$(CONFIG_IOSCHED_SIOPLUS) += sioplus-iosched.o
obj-$(CONFIG_IOSCHED_TRIPNDROID)+= tripndroid-iosched.o
obj-$(CONFIG_IOSCHED_VR) += vr-iosched.o
obj-$(CONFIG_IOSCHED_ZEN) += zen-iosched.o
obj-$(CONFIG_IOSCHED_MAPLE) += maple-iosched.o
obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o
obj-$(CONFIG_BLK_CMDLINE_PARSER) += cmdline-parser.o

424
block/maple-iosched.c Normal file
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@ -0,0 +1,424 @@
/*
* Maple I/O Scheduler
* Based on Zen and SIO.
*
* Copyright (C) 2016 Joe Maples <joe@frap129.org>
* (C) 2012 Brandon Berhent <bbedward@gmail.com
* (C) 2012 Miguel Boton <mboton@gmail.com>
*
* Maple uses a first come first serve style algorithm with seperated read/write
* handling to allow for read biases. By prioritizing reads, simple tasks should improve
* in performance. Maple also uses hooks for the powersuspend driver to increase
* expirations when power is suspended to decrease workload.
*/
#include <linux/blkdev.h>
#include <linux/elevator.h>
#include <linux/bio.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/state_notifier.h>
#define MAPLE_IOSCHED_PATCHLEVEL (8)
enum { ASYNC, SYNC };
/* Tunables */
static const int sync_read_expire = 100; /* max time before a read sync is submitted. */
static const int sync_write_expire = 350; /* max time before a write sync is submitted. */
static const int async_read_expire = 200; /* ditto for read async, these limits are SOFT! */
static const int async_write_expire = 500; /* ditto for write async, these limits are SOFT! */
static const int fifo_batch = 16; /* # of sequential requests treated as one by the above parameters. */
static const int writes_starved = 4; /* max times reads can starve a write */
static const int sleep_latency_multiple = 10; /* multple for expire time when device is asleep */
/* Elevator data */
struct maple_data {
/* Request queues */
struct list_head fifo_list[2][2];
/* Attributes */
unsigned int batched;
unsigned int starved;
/* Settings */
int fifo_expire[2][2];
int fifo_batch;
int writes_starved;
int sleep_latency_multiple;
};
static inline struct maple_data *
maple_get_data(struct request_queue *q) {
return q->elevator->elevator_data;
}
static void
maple_merged_requests(struct request_queue *q, struct request *rq,
struct request *next)
{
/*
* If next expires before rq, assign its expire time to rq
* and move into next position (next will be deleted) in fifo.
*/
if (!list_empty(&rq->queuelist) && !list_empty(&next->queuelist)) {
if (time_before(next->fifo_time, rq->fifo_time)) {
list_move(&rq->queuelist, &next->queuelist);
rq->fifo_time = next->fifo_time;
}
}
/* Delete next request */
rq_fifo_clear(next);
}
static void
maple_add_request(struct request_queue *q, struct request *rq)
{
struct maple_data *mdata = maple_get_data(q);
const int sync = rq_is_sync(rq);
const int dir = rq_data_dir(rq);
/*
* Add request to the proper fifo list and set its
* expire time.
*/
/* inrease expiration when device is asleep */
unsigned int fifo_expire_suspended = mdata->fifo_expire[sync][dir] * sleep_latency_multiple;
if (!state_suspended && mdata->fifo_expire[sync][dir]) {
rq->fifo_time = jiffies + mdata->fifo_expire[sync][dir];
list_add_tail(&rq->queuelist, &mdata->fifo_list[sync][dir]);
} else if (state_suspended && fifo_expire_suspended) {
rq->fifo_time = jiffies + fifo_expire_suspended;
list_add_tail(&rq->queuelist, &mdata->fifo_list[sync][dir]);
}
}
static struct request *
maple_expired_request(struct maple_data *mdata, int sync, int data_dir)
{
struct list_head *list = &mdata->fifo_list[sync][data_dir];
struct request *rq;
if (list_empty(list))
return NULL;
/* Retrieve request */
rq = rq_entry_fifo(list->next);
/* Request has expired */
if (time_after_eq(jiffies, rq->fifo_time))
return rq;
return NULL;
}
static struct request *
maple_choose_expired_request(struct maple_data *mdata)
{
struct request *rq_sync_read = maple_expired_request(mdata, SYNC, READ);
struct request *rq_sync_write = maple_expired_request(mdata, SYNC, WRITE);
struct request *rq_async_read = maple_expired_request(mdata, ASYNC, READ);
struct request *rq_async_write = maple_expired_request(mdata, ASYNC, WRITE);
/* Reset (non-expired-)batch-counter */
mdata->batched = 0;
/*
* Check expired requests.
* Asynchronous requests have priority over synchronous.
* Read requests have priority over write.
*/
if (rq_async_read && rq_sync_read) {
if (time_after(rq_sync_read->fifo_time, rq_async_read->fifo_time))
return rq_async_read;
} else if (rq_async_read) {
return rq_async_read;
} else if (rq_sync_read) {
return rq_sync_read;
}
if (rq_async_write && rq_sync_write) {
if (time_after(rq_sync_write->fifo_time, rq_async_write->fifo_time))
return rq_async_write;
} else if (rq_async_write) {
return rq_async_write;
} else if (rq_sync_write) {
return rq_sync_write;
}
return NULL;
}
static struct request *
maple_choose_request(struct maple_data *mdata, int data_dir)
{
struct list_head *sync = mdata->fifo_list[SYNC];
struct list_head *async = mdata->fifo_list[ASYNC];
/* Increase (non-expired-)batch-counter */
mdata->batched++;
/*
* Retrieve request from available fifo list.
* Asynchronous requests have priority over synchronous.
* Read requests have priority over write.
*/
if (!list_empty(&async[data_dir]))
return rq_entry_fifo(async[data_dir].next);
if (!list_empty(&sync[data_dir]))
return rq_entry_fifo(sync[data_dir].next);
if (!list_empty(&async[!data_dir]))
return rq_entry_fifo(async[!data_dir].next);
if (!list_empty(&sync[!data_dir]))
return rq_entry_fifo(sync[!data_dir].next);
return NULL;
}
static inline void
maple_dispatch_request(struct maple_data *mdata, struct request *rq)
{
/*
* Remove the request from the fifo list
* and dispatch it.
*/
rq_fifo_clear(rq);
elv_dispatch_add_tail(rq->q, rq);
if (rq_data_dir(rq)) {
mdata->starved = 0;
} else {
if (!list_empty(&mdata->fifo_list[SYNC][WRITE]) ||
!list_empty(&mdata->fifo_list[ASYNC][WRITE]))
mdata->starved++;
}
}
static int
maple_dispatch_requests(struct request_queue *q, int force)
{
struct maple_data *mdata = maple_get_data(q);
struct request *rq = NULL;
int data_dir = READ;
/*
* Retrieve any expired request after a batch of
* sequential requests.
*/
if (mdata->batched >= mdata->fifo_batch)
rq = maple_choose_expired_request(mdata);
/* Retrieve request */
if (!rq) {
/* Treat writes fairly while suspended, otherwise allow them to be starved */
if (!state_suspended && mdata->starved >= mdata->writes_starved)
data_dir = WRITE;
else if (state_suspended && mdata->starved >= 1)
data_dir = WRITE;
rq = maple_choose_request(mdata, data_dir);
if (!rq)
return 0;
}
/* Dispatch request */
maple_dispatch_request(mdata, rq);
return 1;
}
static struct request *
maple_former_request(struct request_queue *q, struct request *rq)
{
struct maple_data *mdata = maple_get_data(q);
const int sync = rq_is_sync(rq);
const int data_dir = rq_data_dir(rq);
if (rq->queuelist.prev == &mdata->fifo_list[sync][data_dir])
return NULL;
/* Return former request */
return list_entry(rq->queuelist.prev, struct request, queuelist);
}
static struct request *
maple_latter_request(struct request_queue *q, struct request *rq)
{
struct maple_data *mdata = maple_get_data(q);
const int sync = rq_is_sync(rq);
const int data_dir = rq_data_dir(rq);
if (rq->queuelist.next == &mdata->fifo_list[sync][data_dir])
return NULL;
/* Return latter request */
return list_entry(rq->queuelist.next, struct request, queuelist);
}
static int maple_init_queue(struct request_queue *q, struct elevator_type *e)
{
struct maple_data *mdata;
struct elevator_queue *eq;
eq = elevator_alloc(q, e);
if (!eq)
return -ENOMEM;
/* Allocate structure */
mdata = kmalloc_node(sizeof(*mdata), GFP_KERNEL, q->node);
if (!mdata) {
kobject_put(&eq->kobj);
return -ENOMEM;
}
eq->elevator_data = mdata;
/* Initialize fifo lists */
INIT_LIST_HEAD(&mdata->fifo_list[SYNC][READ]);
INIT_LIST_HEAD(&mdata->fifo_list[SYNC][WRITE]);
INIT_LIST_HEAD(&mdata->fifo_list[ASYNC][READ]);
INIT_LIST_HEAD(&mdata->fifo_list[ASYNC][WRITE]);
/* Initialize data */
mdata->batched = 0;
mdata->fifo_expire[SYNC][READ] = sync_read_expire;
mdata->fifo_expire[SYNC][WRITE] = sync_write_expire;
mdata->fifo_expire[ASYNC][READ] = async_read_expire;
mdata->fifo_expire[ASYNC][WRITE] = async_write_expire;
mdata->fifo_batch = fifo_batch;
mdata->writes_starved = writes_starved;
mdata->sleep_latency_multiple = sleep_latency_multiple;
spin_lock_irq(q->queue_lock);
q->elevator = eq;
spin_unlock_irq(q->queue_lock);
return 0;
}
static void
maple_exit_queue(struct elevator_queue *e)
{
struct maple_data *mdata = e->elevator_data;
/* Free structure */
kfree(mdata);
}
/*
* sysfs code
*/
static ssize_t
maple_var_show(int var, char *page)
{
return sprintf(page, "%d\n", var);
}
static ssize_t
maple_var_store(int *var, const char *page, size_t count)
{
char *p = (char *) page;
*var = simple_strtol(p, &p, 10);
return count;
}
#define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \
static ssize_t __FUNC(struct elevator_queue *e, char *page) \
{ \
struct maple_data *mdata = e->elevator_data; \
int __data = __VAR; \
if (__CONV) \
__data = jiffies_to_msecs(__data); \
return maple_var_show(__data, (page)); \
}
SHOW_FUNCTION(maple_sync_read_expire_show, mdata->fifo_expire[SYNC][READ], 1);
SHOW_FUNCTION(maple_sync_write_expire_show, mdata->fifo_expire[SYNC][WRITE], 1);
SHOW_FUNCTION(maple_async_read_expire_show, mdata->fifo_expire[ASYNC][READ], 1);
SHOW_FUNCTION(maple_async_write_expire_show, mdata->fifo_expire[ASYNC][WRITE], 1);
SHOW_FUNCTION(maple_fifo_batch_show, mdata->fifo_batch, 0);
SHOW_FUNCTION(maple_writes_starved_show, mdata->writes_starved, 0);
SHOW_FUNCTION(maple_sleep_latency_multiple_show, mdata->sleep_latency_multiple, 0);
#undef SHOW_FUNCTION
#define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \
static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count) \
{ \
struct maple_data *mdata = e->elevator_data; \
int __data; \
int ret = maple_var_store(&__data, (page), count); \
if (__data < (MIN)) \
__data = (MIN); \
else if (__data > (MAX)) \
__data = (MAX); \
if (__CONV) \
*(__PTR) = msecs_to_jiffies(__data); \
else \
*(__PTR) = __data; \
return ret; \
}
STORE_FUNCTION(maple_sync_read_expire_store, &mdata->fifo_expire[SYNC][READ], 0, INT_MAX, 1);
STORE_FUNCTION(maple_sync_write_expire_store, &mdata->fifo_expire[SYNC][WRITE], 0, INT_MAX, 1);
STORE_FUNCTION(maple_async_read_expire_store, &mdata->fifo_expire[ASYNC][READ], 0, INT_MAX, 1);
STORE_FUNCTION(maple_async_write_expire_store, &mdata->fifo_expire[ASYNC][WRITE], 0, INT_MAX, 1);
STORE_FUNCTION(maple_fifo_batch_store, &mdata->fifo_batch, 1, INT_MAX, 0);
STORE_FUNCTION(maple_writes_starved_store, &mdata->writes_starved, 1, INT_MAX, 0);
STORE_FUNCTION(maple_sleep_latency_multiple_store, &mdata->sleep_latency_multiple, 1, INT_MAX, 0);
#undef STORE_FUNCTION
#define DD_ATTR(name) \
__ATTR(name, S_IRUGO|S_IWUSR, maple_##name##_show, \
maple_##name##_store)
static struct elv_fs_entry maple_attrs[] = {
DD_ATTR(sync_read_expire),
DD_ATTR(sync_write_expire),
DD_ATTR(async_read_expire),
DD_ATTR(async_write_expire),
DD_ATTR(fifo_batch),
DD_ATTR(writes_starved),
DD_ATTR(sleep_latency_multiple),
__ATTR_NULL
};
static struct elevator_type iosched_maple = {
.ops = {
.elevator_merge_req_fn = maple_merged_requests,
.elevator_dispatch_fn = maple_dispatch_requests,
.elevator_add_req_fn = maple_add_request,
.elevator_former_req_fn = maple_former_request,
.elevator_latter_req_fn = maple_latter_request,
.elevator_init_fn = maple_init_queue,
.elevator_exit_fn = maple_exit_queue,
},
.elevator_attrs = maple_attrs,
.elevator_name = "maple",
.elevator_owner = THIS_MODULE,
};
static int __init maple_init(void)
{
/* Register elevator */
elv_register(&iosched_maple);
return 0;
}
static void __exit maple_exit(void)
{
/* Unregister elevator */
elv_unregister(&iosched_maple);
}
module_init(maple_init);
module_exit(maple_exit);
MODULE_AUTHOR("Joe Maples");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Maple I/O Scheduler");
MODULE_VERSION("1.0");