block: add sysfs file for controlling io stats accounting
This allows us to turn off disk stat accounting completely, for the cases where the 0.5-1% reduction in system time is important. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>hifive-unleashed-5.1
Jens Axboe
parent
7598909e3e
commit
bc58ba9468
|
|
@ -64,11 +64,12 @@ static struct workqueue_struct *kblockd_workqueue;
|
|||
|
||||
static void drive_stat_acct(struct request *rq, int new_io)
|
||||
{
|
||||
struct gendisk *disk = rq->rq_disk;
|
||||
struct hd_struct *part;
|
||||
int rw = rq_data_dir(rq);
|
||||
int cpu;
|
||||
|
||||
if (!blk_fs_request(rq) || !rq->rq_disk)
|
||||
if (!blk_fs_request(rq) || !disk || !blk_queue_io_stat(disk->queue))
|
||||
return;
|
||||
|
||||
cpu = part_stat_lock();
|
||||
|
|
@ -599,8 +600,7 @@ blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id)
|
|||
q->request_fn = rfn;
|
||||
q->prep_rq_fn = NULL;
|
||||
q->unplug_fn = generic_unplug_device;
|
||||
q->queue_flags = (1 << QUEUE_FLAG_CLUSTER |
|
||||
1 << QUEUE_FLAG_STACKABLE);
|
||||
q->queue_flags = QUEUE_FLAG_DEFAULT;
|
||||
q->queue_lock = lock;
|
||||
|
||||
blk_queue_segment_boundary(q, BLK_SEG_BOUNDARY_MASK);
|
||||
|
|
@ -1663,6 +1663,55 @@ void blkdev_dequeue_request(struct request *req)
|
|||
}
|
||||
EXPORT_SYMBOL(blkdev_dequeue_request);
|
||||
|
||||
static void blk_account_io_completion(struct request *req, unsigned int bytes)
|
||||
{
|
||||
struct gendisk *disk = req->rq_disk;
|
||||
|
||||
if (!disk || !blk_queue_io_stat(disk->queue))
|
||||
return;
|
||||
|
||||
if (blk_fs_request(req)) {
|
||||
const int rw = rq_data_dir(req);
|
||||
struct hd_struct *part;
|
||||
int cpu;
|
||||
|
||||
cpu = part_stat_lock();
|
||||
part = disk_map_sector_rcu(req->rq_disk, req->sector);
|
||||
part_stat_add(cpu, part, sectors[rw], bytes >> 9);
|
||||
part_stat_unlock();
|
||||
}
|
||||
}
|
||||
|
||||
static void blk_account_io_done(struct request *req)
|
||||
{
|
||||
struct gendisk *disk = req->rq_disk;
|
||||
|
||||
if (!disk || !blk_queue_io_stat(disk->queue))
|
||||
return;
|
||||
|
||||
/*
|
||||
* Account IO completion. bar_rq isn't accounted as a normal
|
||||
* IO on queueing nor completion. Accounting the containing
|
||||
* request is enough.
|
||||
*/
|
||||
if (blk_fs_request(req) && req != &req->q->bar_rq) {
|
||||
unsigned long duration = jiffies - req->start_time;
|
||||
const int rw = rq_data_dir(req);
|
||||
struct hd_struct *part;
|
||||
int cpu;
|
||||
|
||||
cpu = part_stat_lock();
|
||||
part = disk_map_sector_rcu(disk, req->sector);
|
||||
|
||||
part_stat_inc(cpu, part, ios[rw]);
|
||||
part_stat_add(cpu, part, ticks[rw], duration);
|
||||
part_round_stats(cpu, part);
|
||||
part_dec_in_flight(part);
|
||||
|
||||
part_stat_unlock();
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* __end_that_request_first - end I/O on a request
|
||||
* @req: the request being processed
|
||||
|
|
@ -1698,16 +1747,7 @@ static int __end_that_request_first(struct request *req, int error,
|
|||
(unsigned long long)req->sector);
|
||||
}
|
||||
|
||||
if (blk_fs_request(req) && req->rq_disk) {
|
||||
const int rw = rq_data_dir(req);
|
||||
struct hd_struct *part;
|
||||
int cpu;
|
||||
|
||||
cpu = part_stat_lock();
|
||||
part = disk_map_sector_rcu(req->rq_disk, req->sector);
|
||||
part_stat_add(cpu, part, sectors[rw], nr_bytes >> 9);
|
||||
part_stat_unlock();
|
||||
}
|
||||
blk_account_io_completion(req, nr_bytes);
|
||||
|
||||
total_bytes = bio_nbytes = 0;
|
||||
while ((bio = req->bio) != NULL) {
|
||||
|
|
@ -1787,8 +1827,6 @@ static int __end_that_request_first(struct request *req, int error,
|
|||
*/
|
||||
static void end_that_request_last(struct request *req, int error)
|
||||
{
|
||||
struct gendisk *disk = req->rq_disk;
|
||||
|
||||
if (blk_rq_tagged(req))
|
||||
blk_queue_end_tag(req->q, req);
|
||||
|
||||
|
|
@ -1800,27 +1838,7 @@ static void end_that_request_last(struct request *req, int error)
|
|||
|
||||
blk_delete_timer(req);
|
||||
|
||||
/*
|
||||
* Account IO completion. bar_rq isn't accounted as a normal
|
||||
* IO on queueing nor completion. Accounting the containing
|
||||
* request is enough.
|
||||
*/
|
||||
if (disk && blk_fs_request(req) && req != &req->q->bar_rq) {
|
||||
unsigned long duration = jiffies - req->start_time;
|
||||
const int rw = rq_data_dir(req);
|
||||
struct hd_struct *part;
|
||||
int cpu;
|
||||
|
||||
cpu = part_stat_lock();
|
||||
part = disk_map_sector_rcu(disk, req->sector);
|
||||
|
||||
part_stat_inc(cpu, part, ios[rw]);
|
||||
part_stat_add(cpu, part, ticks[rw], duration);
|
||||
part_round_stats(cpu, part);
|
||||
part_dec_in_flight(part);
|
||||
|
||||
part_stat_unlock();
|
||||
}
|
||||
blk_account_io_done(req);
|
||||
|
||||
if (req->end_io)
|
||||
req->end_io(req, error);
|
||||
|
|
|
|||
|
|
@ -197,6 +197,27 @@ queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
|
|||
return ret;
|
||||
}
|
||||
|
||||
static ssize_t queue_iostats_show(struct request_queue *q, char *page)
|
||||
{
|
||||
return queue_var_show(blk_queue_io_stat(q), page);
|
||||
}
|
||||
|
||||
static ssize_t queue_iostats_store(struct request_queue *q, const char *page,
|
||||
size_t count)
|
||||
{
|
||||
unsigned long stats;
|
||||
ssize_t ret = queue_var_store(&stats, page, count);
|
||||
|
||||
spin_lock_irq(q->queue_lock);
|
||||
if (stats)
|
||||
queue_flag_set(QUEUE_FLAG_IO_STAT, q);
|
||||
else
|
||||
queue_flag_clear(QUEUE_FLAG_IO_STAT, q);
|
||||
spin_unlock_irq(q->queue_lock);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static struct queue_sysfs_entry queue_requests_entry = {
|
||||
.attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
|
||||
.show = queue_requests_show,
|
||||
|
|
@ -249,6 +270,12 @@ static struct queue_sysfs_entry queue_rq_affinity_entry = {
|
|||
.store = queue_rq_affinity_store,
|
||||
};
|
||||
|
||||
static struct queue_sysfs_entry queue_iostats_entry = {
|
||||
.attr = {.name = "iostats", .mode = S_IRUGO | S_IWUSR },
|
||||
.show = queue_iostats_show,
|
||||
.store = queue_iostats_store,
|
||||
};
|
||||
|
||||
static struct attribute *default_attrs[] = {
|
||||
&queue_requests_entry.attr,
|
||||
&queue_ra_entry.attr,
|
||||
|
|
@ -259,6 +286,7 @@ static struct attribute *default_attrs[] = {
|
|||
&queue_nonrot_entry.attr,
|
||||
&queue_nomerges_entry.attr,
|
||||
&queue_rq_affinity_entry.attr,
|
||||
&queue_iostats_entry.attr,
|
||||
NULL,
|
||||
};
|
||||
|
||||
|
|
|
|||
|
|
@ -451,6 +451,11 @@ struct request_queue
|
|||
#define QUEUE_FLAG_STACKABLE 13 /* supports request stacking */
|
||||
#define QUEUE_FLAG_NONROT 14 /* non-rotational device (SSD) */
|
||||
#define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
|
||||
#define QUEUE_FLAG_IO_STAT 15 /* do IO stats */
|
||||
|
||||
#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
|
||||
(1 << QUEUE_FLAG_CLUSTER) | \
|
||||
1 << QUEUE_FLAG_STACKABLE)
|
||||
|
||||
static inline int queue_is_locked(struct request_queue *q)
|
||||
{
|
||||
|
|
@ -567,6 +572,7 @@ enum {
|
|||
#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
|
||||
#define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
|
||||
#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
|
||||
#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
|
||||
#define blk_queue_flushing(q) ((q)->ordseq)
|
||||
#define blk_queue_stackable(q) \
|
||||
test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
|
||||
|
|
|
|||
Loading…
Reference in New Issue