linux-stable/include/linux/part_stat.h
Christoph Hellwig c6a564ffad block: move the part_stat* helpers from genhd.h to a new header
These macros are just used by a few files.  Move them out of genhd.h,
which is included everywhere into a new standalone header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-25 09:50:09 -06:00

115 lines
3.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_PART_STAT_H
#define _LINUX_PART_STAT_H
#include <linux/genhd.h>
/*
* Macros to operate on percpu disk statistics:
*
* {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
* and should be called between disk_stat_lock() and
* disk_stat_unlock().
*
* part_stat_read() can be called at any time.
*
* part_stat_{add|set_all}() and {init|free}_part_stats are for
* internal use only.
*/
#ifdef CONFIG_SMP
#define part_stat_lock() ({ rcu_read_lock(); get_cpu(); })
#define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0)
#define part_stat_get_cpu(part, field, cpu) \
(per_cpu_ptr((part)->dkstats, (cpu))->field)
#define part_stat_get(part, field) \
part_stat_get_cpu(part, field, smp_processor_id())
#define part_stat_read(part, field) \
({ \
typeof((part)->dkstats->field) res = 0; \
unsigned int _cpu; \
for_each_possible_cpu(_cpu) \
res += per_cpu_ptr((part)->dkstats, _cpu)->field; \
res; \
})
static inline void part_stat_set_all(struct hd_struct *part, int value)
{
int i;
for_each_possible_cpu(i)
memset(per_cpu_ptr(part->dkstats, i), value,
sizeof(struct disk_stats));
}
static inline int init_part_stats(struct hd_struct *part)
{
part->dkstats = alloc_percpu(struct disk_stats);
if (!part->dkstats)
return 0;
return 1;
}
static inline void free_part_stats(struct hd_struct *part)
{
free_percpu(part->dkstats);
}
#else /* !CONFIG_SMP */
#define part_stat_lock() ({ rcu_read_lock(); 0; })
#define part_stat_unlock() rcu_read_unlock()
#define part_stat_get(part, field) ((part)->dkstats.field)
#define part_stat_get_cpu(part, field, cpu) part_stat_get(part, field)
#define part_stat_read(part, field) part_stat_get(part, field)
static inline void part_stat_set_all(struct hd_struct *part, int value)
{
memset(&part->dkstats, value, sizeof(struct disk_stats));
}
static inline int init_part_stats(struct hd_struct *part)
{
return 1;
}
static inline void free_part_stats(struct hd_struct *part)
{
}
#endif /* CONFIG_SMP */
#define part_stat_read_accum(part, field) \
(part_stat_read(part, field[STAT_READ]) + \
part_stat_read(part, field[STAT_WRITE]) + \
part_stat_read(part, field[STAT_DISCARD]))
#define __part_stat_add(part, field, addnd) \
(part_stat_get(part, field) += (addnd))
#define part_stat_add(part, field, addnd) do { \
__part_stat_add((part), field, addnd); \
if ((part)->partno) \
__part_stat_add(&part_to_disk((part))->part0, \
field, addnd); \
} while (0)
#define part_stat_dec(gendiskp, field) \
part_stat_add(gendiskp, field, -1)
#define part_stat_inc(gendiskp, field) \
part_stat_add(gendiskp, field, 1)
#define part_stat_sub(gendiskp, field, subnd) \
part_stat_add(gendiskp, field, -subnd)
#define part_stat_local_dec(gendiskp, field) \
local_dec(&(part_stat_get(gendiskp, field)))
#define part_stat_local_inc(gendiskp, field) \
local_inc(&(part_stat_get(gendiskp, field)))
#define part_stat_local_read(gendiskp, field) \
local_read(&(part_stat_get(gendiskp, field)))
#define part_stat_local_read_cpu(gendiskp, field, cpu) \
local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
#endif /* _LINUX_PART_STAT_H */