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#ifndef _LINUX_PSI_TYPES_H
#define _LINUX_PSI_TYPES_H
#include <linux/seqlock.h>
#include <linux/types.h>
#ifdef CONFIG_PSI
/* Tracked task states */
enum psi_task_count {
NR_IOWAIT,
NR_MEMSTALL,
NR_RUNNING,
NR_PSI_TASK_COUNTS,
};
/* Task state bitmasks */
#define TSK_IOWAIT (1 << NR_IOWAIT)
#define TSK_MEMSTALL (1 << NR_MEMSTALL)
#define TSK_RUNNING (1 << NR_RUNNING)
/* Resources that workloads could be stalled on */
enum psi_res {
PSI_IO,
PSI_MEM,
PSI_CPU,
NR_PSI_RESOURCES,
};
/*
* Pressure states for each resource:
*
* SOME: Stalled tasks & working tasks
* FULL: Stalled tasks & no working tasks
*/
enum psi_states {
PSI_IO_SOME,
PSI_IO_FULL,
PSI_MEM_SOME,
PSI_MEM_FULL,
PSI_CPU_SOME,
/* Only per-CPU, to weigh the CPU in the global average: */
PSI_NONIDLE,
NR_PSI_STATES,
};
struct psi_group_cpu {
/* 1st cacheline updated by the scheduler */
/* Aggregator needs to know of concurrent changes */
seqcount_t seq ____cacheline_aligned_in_smp;
/* States of the tasks belonging to this group */
unsigned int tasks[NR_PSI_TASK_COUNTS];
/* Period time sampling buckets for each state of interest (ns) */
u32 times[NR_PSI_STATES];
/* Time of last task change in this group (rq_clock) */
u64 state_start;
/* 2nd cacheline updated by the aggregator */
/* Delta detection against the sampling buckets */
u32 times_prev[NR_PSI_STATES] ____cacheline_aligned_in_smp;
};
struct psi_group {
/* Protects data updated during an aggregation */
struct mutex stat_lock;
/* Per-cpu task state & time tracking */
struct psi_group_cpu __percpu *pcpu;
/* Periodic aggregation state */
u64 total_prev[NR_PSI_STATES - 1];
u64 last_update;
u64 next_update;
struct delayed_work clock_work;
/* Total stall times and sampled pressure averages */
u64 total[NR_PSI_STATES - 1];
unsigned long avg[NR_PSI_STATES - 1][3];
};
#else /* CONFIG_PSI */
struct psi_group { };
#endif /* CONFIG_PSI */
#endif /* _LINUX_PSI_TYPES_H */
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