kernel_optimize_test/include/linux/part_stat.h
Konstantin Khlebnikov b2d76adbc0 block: use __this_cpu_add() instead of access by smp_processor_id()
Most architectures have fast path to access percpu for current cpu.
The required preempt_disable() is provided by part_stat_lock().

[hch: rebased]

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:21:23 -06:00

83 lines
2.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_PART_STAT_H
#define _LINUX_PART_STAT_H
#include <linux/genhd.h>
struct disk_stats {
u64 nsecs[NR_STAT_GROUPS];
unsigned long sectors[NR_STAT_GROUPS];
unsigned long ios[NR_STAT_GROUPS];
unsigned long merges[NR_STAT_GROUPS];
unsigned long io_ticks;
local_t in_flight[2];
};
/*
* 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.
*/
#define part_stat_lock() preempt_disable()
#define part_stat_unlock() preempt_enable()
#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));
}
#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) \
__this_cpu_add((part)->dkstats->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 */