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     ˆÃÂƒx!oÁÀ¿ ³    /* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_CPUSET_H
#define _LINUX_CPUSET_H
/*
 *  cpuset interface
 *
 *  Copyright (C) 2003 BULL SA
 *  Copyright (C) 2004-2006 Silicon Graphics, Inc.
 *
 */

#include <linux/sched.h>
#include <linux/sched/topology.h>
#include <linux/sched/task.h>
#include <linux/cpumask.h>
#include <linux/nodemask.h>
#include <linux/mm.h>
#include <linux/mmu_context.h>
#include <linux/jump_label.h>

#ifdef CONFIG_CPUSETS

/*
 * Static branch rewrites can happen in an arbitrary order for a given
 * key. In code paths where we need to loop with read_mems_allowed_begin() and
 * read_mems_allowed_retry() to get a consistent view of mems_allowed, we need
 * to ensure that begin() always gets rewritten before retry() in the
 * disabled -> enabled transition. If not, then if local irqs are disabled
 * around the loop, we can deadlock since retry() would always be
 * comparing the latest value of the mems_allowed seqcount against 0 as
 * begin() still would see cpusets_enabled() as false. The enabled -> disabled
 * transition should happen in reverse order for the same reasons (want to stop
 * looking at real value of mems_allowed.sequence in retry() first).
 */
extern struct static_key_false cpusets_pre_enable_key;
extern struct static_key_false cpusets_enabled_key;
extern struct static_key_false cpusets_insane_config_key;

static inline bool cpusets_enabled(void)
{
	return static_branch_unlikely(&cpusets_enabled_key);
}

static inline void cpuset_inc(void)
{
	static_branch_inc_cpuslocked(&cpusets_pre_enable_key);
	static_branch_inc_cpuslocked(&cpusets_enabled_key);
}

static inline void cpuset_dec(void)
{
	static_branch_dec_cpuslocked(&cpusets_enabled_key);
	static_branch_dec_cpuslocked(&cpusets_pre_enable_key);
}

/*
 * This will get enabled whenever a cpuset configuration is considered
 * unsupportable in general. E.g. movable only node which cannot satisfy
 * any non movable allocations (see update_nodemask). Page allocator
 * needs to make additional checks for those configurations and this
 * check is meant to guard those checks without any overhead for sane
 * configurations.
 */
static inline bool cpusets_insane_config(void)
{
	return static_branch_unlikely(&cpusets_insane_config_key);
}

extern int cpuset_init(void);
extern void cpuset_init_smp(void);
extern void cpuset_force_rebuild(void);
extern void cpuset_update_active_cpus(void);
extern void inc_dl_tasks_cs(struct task_struct *task);
extern void dec_dl_tasks_cs(struct task_struct *task);
extern void cpuset_lock(void);
extern void cpuset_unlock(void);
extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
extern bool cpuset_cpus_allowed_fallback(struct task_struct *p);
extern bool cpuset_cpu_is_isolated(int cpu);
extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
#define cpuset_current_mems_allowed (current->mems_allowed)
void cpuset_init_current_mems_allowed(void);
int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask);

extern bool cpuset_node_allowed(int node, gfp_t gfp_mask);

static inline bool __cpuset_zone_allowed(struct zone *z, gfp_t gfp_mask)
{
	return cpuset_node_allowed(zone_to_nid(z), gfp_mask);
}

static inline bool cpuset_zone_allowed(struct zone *z, gfp_t gfp_mask)
{
	if (cpusets_enabled())
		return __cpuset_zone_allowed(z, gfp_mask);
	return true;
}

extern int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
					  const struct task_struct *tsk2);

#ifdef CONFIG_CPUSETS_V1
#define cpuset_memory_pressure_bump() 				\
	do {							\
		if (cpuset_memory_pressure_enabled)		\
			__cpuset_memory_pressure_bump();	\
	} while (0)
extern int cpuset_memory_pressure_enabled;
extern void __cpuset_memory_pressure_bump(void);
#else
static inline void cpuset_memory_pressure_bump(void) { }
#endif

extern void cpuset_task_status_allowed(struct seq_file *m,
					struct task_struct *task);
extern int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns,
			    struct pid *pid, struct task_struct *tsk);

extern int cpuset_mem_spread_node(void);