MIRRORS/linux-yocto
1
0
Fork 0
mirror of git://git.yoctoproject.org/linux-yocto.git synced 2025-10-23 07:23:12 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity

block: export API to get the number of bdev inflight IO

Browse Source 
- rename part_in_{flight, flight_rw} to bdev_count_{inflight, inflight_rw}
- export bdev_count_inflight, to fix a problem in mdraid that foreground
  IO can be starved by background sync IO in later patches

Link: https://lore.kernel.org/linux-raid/20250506124903.2540268-6-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
This commit is contained in:
Yu Kuai 2025-05-06 20:48:59 +08:00
parent 6b6c3a97ab
commit f2987c5816
4 changed files with 19 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
block/blk-core.c
View File

@ -1018,7 +1018,7 @@ again:
stamp = READ_ONCE(part->bd_stamp); stamp = READ_ONCE(part->bd_stamp);
if (unlikely(time_after(now, stamp)) && if (unlikely(time_after(now, stamp)) &&
likely(try_cmpxchg(&part->bd_stamp, &stamp, now)) && likely(try_cmpxchg(&part->bd_stamp, &stamp, now)) &&
(end || part_in_flight(part))) (end || bdev_count_inflight(part)))
__part_stat_add(part, io_ticks, now - stamp); __part_stat_add(part, io_ticks, now - stamp);
if (bdev_is_partition(part)) { if (bdev_is_partition(part)) {

1
block/blk.h
View File

@ -419,7 +419,6 @@ void blk_apply_bdi_limits(struct backing_dev_info *bdi,
int blk_dev_init(void); int blk_dev_init(void);
void update_io_ticks(struct block_device *part, unsigned long now, bool end); void update_io_ticks(struct block_device *part, unsigned long now, bool end);
unsigned int part_in_flight(struct block_device *part);
static inline void req_set_nomerge(struct request_queue *q, struct request *req) static inline void req_set_nomerge(struct request_queue *q, struct request *req)
{ {

22
block/genhd.c
View File

@ -125,7 +125,7 @@ static void part_stat_read_all(struct block_device *part,
} }
} }
static void part_in_flight_rw(struct block_device *part, static void bdev_count_inflight_rw(struct block_device *part,
unsigned int inflight[2], bool mq_driver) unsigned int inflight[2], bool mq_driver)
{ {
int cpu; int cpu;
@ -147,14 +147,24 @@ static void part_in_flight_rw(struct block_device *part,
inflight[WRITE] = 0; inflight[WRITE] = 0;
} }
unsigned int part_in_flight(struct block_device *part) /**
* bdev_count_inflight - get the number of inflight IOs for a block device.
*
* @part: the block device.
*
* Inflight here means started IO accounting, from bdev_start_io_acct() for
* bio-based block device, and from blk_account_io_start() for rq-based block
* device.
*/
unsigned int bdev_count_inflight(struct block_device *part)
{ {
unsigned int inflight[2] = {0}; unsigned int inflight[2] = {0};
part_in_flight_rw(part, inflight, false); bdev_count_inflight_rw(part, inflight, false);
return inflight[READ] + inflight[WRITE]; return inflight[READ] + inflight[WRITE];
} }
EXPORT_SYMBOL_GPL(bdev_count_inflight);
/* /*
* Can be deleted altogether. Later. * Can be deleted altogether. Later.
@ -1052,7 +1062,7 @@ ssize_t part_stat_show(struct device *dev,
struct disk_stats stat; struct disk_stats stat;
unsigned int inflight; unsigned int inflight;
inflight = part_in_flight(bdev); inflight = bdev_count_inflight(bdev);
if (inflight) { if (inflight) {
part_stat_lock(); part_stat_lock();
update_io_ticks(bdev, jiffies, true); update_io_ticks(bdev, jiffies, true);
@ -1101,7 +1111,7 @@ ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
struct request_queue *q = bdev_get_queue(bdev); struct request_queue *q = bdev_get_queue(bdev);
unsigned int inflight[2] = {0}; unsigned int inflight[2] = {0};
part_in_flight_rw(bdev, inflight, queue_is_mq(q)); bdev_count_inflight_rw(bdev, inflight, queue_is_mq(q));
return sysfs_emit(buf, "%8u %8u\n", inflight[READ], inflight[WRITE]); return sysfs_emit(buf, "%8u %8u\n", inflight[READ], inflight[WRITE]);
} }
@ -1356,7 +1366,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
if (bdev_is_partition(hd) && !bdev_nr_sectors(hd)) if (bdev_is_partition(hd) && !bdev_nr_sectors(hd))
continue; continue;
inflight = part_in_flight(hd); inflight = bdev_count_inflight(hd);
if (inflight) { if (inflight) {
part_stat_lock(); part_stat_lock();
update_io_ticks(hd, jiffies, true); update_io_ticks(hd, jiffies, true);

2
include/linux/part_stat.h
View File

@ -79,4 +79,6 @@ static inline void part_stat_set_all(struct block_device *part, int value)
#define part_stat_local_read_cpu(part, field, cpu) \ #define part_stat_local_read_cpu(part, field, cpu) \
local_read(&(part_stat_get_cpu(part, field, cpu))) local_read(&(part_stat_get_cpu(part, field, cpu)))
unsigned int bdev_count_inflight(struct block_device *part);
#endif /* _LINUX_PART_STAT_H */ #endif /* _LINUX_PART_STAT_H */