sched.h

unxi下共享内存的使用

#ifndef _LINUX_SCHED_H
#define _LINUX_SCHED_H

#include <asm/param.h>	/* for HZ */

extern unsigned long event;

#include <linux/config.h>
#include <linux/compiler.h>
#include <linux/binfmts.h>
#include <linux/threads.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/times.h>
#include <linux/timex.h>
#include <linux/rbtree.h>
#include <linux/condsched.h>

#include <asm/system.h>
#include <asm/semaphore.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/mmu.h>

#include <linux/smp.h>
//#include <linux/tty.h>
#include <linux/sem.h>
#include <linux/signal.h>
#include <linux/securebits.h>
#include <linux/fs_struct.h>

struct exec_domain;

/*
 * cloning flags:
 */
#define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
#define CLONE_VM	0x00000100	/* set if VM shared between processes */
#define CLONE_FS	0x00000200	/* set if fs info shared between processes */
#define CLONE_FILES	0x00000400	/* set if open files shared between processes */
#define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
#define CLONE_PID	0x00001000	/* set if pid shared */
#define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
#define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
#define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
#define CLONE_THREAD	0x00010000	/* Same thread group? */
#define CLONE_NEWNS	0x00020000	/* New namespace group? */

#define CLONE_SIGNAL	(CLONE_SIGHAND | CLONE_THREAD)

/*
 * These are the constant used to fake the fixed-point load-average
 * counting. Some notes:
 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 *    a load-average precision of 10 bits integer + 11 bits fractional
 *  - if you want to count load-averages more often, you need more
 *    precision, or rounding will get you. With 2-second counting freq,
 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 *    11 bit fractions.
 */
extern unsigned long avenrun[];		/* Load averages */

#define FSHIFT		11		/* nr of bits of precision */
#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
#define LOAD_FREQ	(5*HZ)		/* 5 sec intervals */
#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
#define EXP_5		2014		/* 1/exp(5sec/5min) */
#define EXP_15		2037		/* 1/exp(5sec/15min) */

#define CALC_LOAD(load,exp,n) \
	load *= exp; \
	load += n*(FIXED_1-exp); \
	load >>= FSHIFT;

#define CT_TO_SECS(x)	((x) / HZ)
#define CT_TO_USECS(x)	(((x) % HZ) * 1000000/HZ)

extern int nr_threads;
extern int last_pid;
extern unsigned long nr_running(void);

//#include <linux/fs.h>
#include <linux/time.h>
#include <linux/param.h>
#include <linux/resource.h>
#ifdef __KERNEL__
#include <linux/timer.h>
#endif

#include <asm/processor.h>

#define TASK_RUNNING		0
#define TASK_INTERRUPTIBLE	1
#define TASK_UNINTERRUPTIBLE	2
#define TASK_ZOMBIE		4
#define TASK_STOPPED		8

#define __set_task_state(tsk, state_value)		\
	do { (tsk)->state = (state_value); } while (0)
#ifdef CONFIG_SMP
#define set_task_state(tsk, state_value)		\
	set_mb((tsk)->state, (state_value))
#else
#define set_task_state(tsk, state_value)		\
	__set_task_state((tsk), (state_value))
#endif

#define __set_current_state(state_value)			\
	do { current->state = (state_value); } while (0)
#ifdef CONFIG_SMP
#define set_current_state(state_value)		\
	set_mb(current->state, (state_value))
#else
#define set_current_state(state_value)		\
	__set_current_state(state_value)
#endif

/*
 * Scheduling policies
 */
#define SCHED_OTHER		0
#define SCHED_FIFO		1
#define SCHED_RR		2

struct sched_param {
	int sched_priority;
};

struct completion;

#ifdef __KERNEL__

#include <linux/spinlock.h>

/*
 * This serializes "schedule()" and also protects
 * the run-queue from deletions/modifications (but
 * _adding_ to the beginning of the run-queue has
 * a separate lock).
 */
extern rwlock_t tasklist_lock;
extern spinlock_t mmlist_lock;

typedef struct task_struct task_t;

extern void sched_init(void);
extern void init_idle(task_t *idle, int cpu);
extern void show_state(void);
extern void cpu_init (void);
extern void trap_init(void);
extern void update_process_times(int user);
extern void update_one_process(task_t *p, unsigned long user,
			       unsigned long system, int cpu);
extern void scheduler_tick(int user_tick, int system);
extern void migration_init(void);
extern unsigned long cache_decay_ticks;

#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
extern signed long FASTCALL(schedule_timeout(signed long timeout));
asmlinkage void schedule(void);

extern int schedule_task(struct tq_struct *task);
extern void flush_scheduled_tasks(void);
extern int start_context_thread(void);
extern int current_is_keventd(void);
extern void force_cpu_reschedule(int cpu);

/*
 * The maximum RT priority is configurable.  If the resulting
 * bitmap is 160-bits , we can use a hand-coded routine which
 * is optimal.  Otherwise, we fall back on a generic routine for
 * finding the first set bit from an arbitrarily-sized bitmap.
 */
#if MAX_PRIO < 160 && MAX_PRIO > 127
#define sched_find_first_bit(map)	_sched_find_first_bit(map)
#else
#define sched_find_first_bit(map)	find_first_bit(map, MAX_PRIO)
#endif

/*
 * The default fd array needs to be at least BITS_PER_LONG,
 * as this is the granularity returned by copy_fdset().
 */
#define NR_OPEN_DEFAULT BITS_PER_LONG

struct namespace;
/*
 * Open file table structure
 */
struct files_struct {
	atomic_t count;
	rwlock_t file_lock;	/* Protects all the below members.  Nests inside tsk->alloc_lock */
	int max_fds;
	int max_fdset;
	int next_fd;
	struct file ** fd;	/* current fd array */
	fd_set *close_on_exec;
	fd_set *open_fds;
	fd_set close_on_exec_init;
	fd_set open_fds_init;
	struct file * fd_array[NR_OPEN_DEFAULT];
};

#define INIT_FILES \
{ 							\
	count:		ATOMIC_INIT(1), 		\
	file_lock:	RW_LOCK_UNLOCKED, 		\
	max_fds:	NR_OPEN_DEFAULT, 		\
	max_fdset:	__FD_SETSIZE, 			\
	next_fd:	0, 				\
	fd:		&init_files.fd_array[0], 	\
	close_on_exec:	&init_files.close_on_exec_init, \
	open_fds:	&init_files.open_fds_init, 	\
	close_on_exec_init: { { 0, } }, 		\
	open_fds_init:	{ { 0, } }, 			\
	fd_array:	{ NULL, } 			\
}

/* Maximum number of active map areas.. This is a random (large) number */
#define DEFAULT_MAX_MAP_COUNT	(65536)

extern int max_map_count;

struct mm_struct {
	struct vm_area_struct * mmap;		/* list of VMAs */
	rb_root_t mm_rb;
	struct vm_area_struct * mmap_cache;	/* last find_vma result */
	pgd_t * pgd;
	atomic_t mm_users;			/* How many users with user space? */
	atomic_t mm_count;			/* How many references to "struct mm_struct" (users count as 1) */
	int map_count;				/* number of VMAs */
	struct rw_semaphore mmap_sem;
	spinlock_t page_table_lock;		/* Protects task page tables and mm->rss */

	struct list_head mmlist;		/* List of all active mm's.  These are globally strung
						 * together off init_mm.mmlist, and are protected
						 * by mmlist_lock
						 */

	unsigned long start_code, end_code, start_data, end_data;
	unsigned long start_brk, brk, start_stack;
	unsigned long arg_start, arg_end, env_start, env_end;
	unsigned long rss, total_vm, locked_vm;
	unsigned long def_flags;
	unsigned long cpu_vm_mask;
	unsigned long swap_address;

	unsigned dumpable:1;

	/* Architecture-specific MM context */
	mm_context_t context;
};

extern int mmlist_nr;

#define INIT_MM(name) \
{			 				\
	mm_rb:		RB_ROOT,			\
	pgd:		swapper_pg_dir, 		\
	mm_users:	ATOMIC_INIT(2), 		\
	mm_count:	ATOMIC_INIT(1), 		\
	mmap_sem:	RWSEM_INITIALIZER(name.mmap_sem), \
	page_table_lock: SPIN_LOCK_UNLOCKED, 		\
	mmlist:		LIST_HEAD_INIT(name.mmlist),	\
}

struct signal_struct {
	atomic_t		count;
	struct k_sigaction	action[_NSIG];
	spinlock_t		siglock;
};


#define INIT_SIGNALS {	\
	count:		ATOMIC_INIT(1), 		\
	action:		{ {{0,}}, }, 			\
	siglock:	SPIN_LOCK_UNLOCKED 		\
}

/*
 * Some day this will be a full-fledged user tracking system..
 */
struct user_struct {
	atomic_t __count;	/* reference count */
	atomic_t processes;	/* How many processes does this user have? */
	atomic_t files;		/* How many open files does this user have? */

	/* Hash table maintenance information */
	struct user_struct *next, **pprev;
	uid_t uid;
};

#define get_current_user() ({ 				\
	struct user_struct *__user = current->user;	\
	atomic_inc(&__user->__count);			\
	__user; })

extern struct user_struct root_user;
#define INIT_USER (&root_user)

typedef struct prio_array prio_array_t;

struct zone_struct;

struct local_pages {
	struct list_head list;
	unsigned int order, nr;
	struct zone_struct * classzone;
};

struct task_struct {
	/*
	 * offsets of these are hardcoded elsewhere - touch with care
	 */
	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
	unsigned long flags;	/* per process flags, defined below */
	int sigpending;
	mm_segment_t addr_limit;	/* thread address space:
					 	0-0xBFFFFFFF for user-thead
						0-0xFFFFFFFF for kernel-thread
					 */
	struct exec_domain *exec_domain;
	volatile long need_resched;
	unsigned long ptrace;

	int lock_depth;		/* Lock depth */

	/*
	 * offset 32 begins here on 32-bit platforms.
	 */
	unsigned int cpu;
	int prio, static_prio;
	list_t run_list;
	prio_array_t *array;

	unsigned long sleep_avg;
	unsigned long sleep_timestamp;

	unsigned long policy;
	unsigned long cpus_allowed;
	unsigned int time_slice;
	int get_child_timeslice;

	task_t *next_task, *prev_task;

	struct mm_struct *mm, *active_mm;
	struct local_pages local_pages;

/* task state */
	struct linux_binfmt *binfmt;
	int exit_code, exit_signal;
	int pdeath_signal;  /*  The signal sent when the parent dies  */
	/* ??? */
	unsigned long personality;
	int did_exec:1;
	pid_t pid;
	pid_t pgrp;
	pid_t tty_old_pgrp;
	pid_t session;
	pid_t tgid;
	/* boolean value for session group leader */
	int leader;
	/* 
	 * pointers to (original) parent process, youngest child, younger sibling,
	 * older sibling, respectively.  (p->father can be replaced with 
	 * p->p_pptr->pid)
	 */
	task_t *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
	struct list_head thread_group;

	/* PID hash table linkage. */
	task_t *pidhash_next;
	task_t **pidhash_pprev;

	wait_queue_head_t wait_chldexit;	/* for wait4() */
	struct completion *vfork_done;		/* for vfork() */
	unsigned long rt_priority;
	unsigned long it_real_value, it_prof_value, it_virt_value;
	unsigned long it_real_incr, it_prof_incr, it_virt_incr;
	struct timer_list real_timer;
	struct tms times;
	unsigned long start_time;
	long per_cpu_utime[NR_CPUS], per_cpu_stime[NR_CPUS];
/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
	unsigned long min_flt, maj_flt, nswap, cmin_flt, cmaj_flt, cnswap;
	int swappable:1;
/* process credentials */
	uid_t uid,euid,suid,fsuid;
	gid_t gid,egid,sgid,fsgid;
	int ngroups;
	gid_t	groups[NGROUPS];
	kernel_cap_t   cap_effective, cap_inheritable, cap_permitted;
	int keep_capabilities:1;
	struct user_struct *user;
/* limits */
	struct rlimit rlim[RLIM_NLIMITS];
	unsigned short used_math;
	char comm[16];
/* file system info */
	int link_count, total_link_count;
	struct tty_struct *tty; /* NULL if no tty */
	unsigned int locks; /* How many file locks are being held */
/* ipc stuff */
	struct sem_undo *semundo;
	struct sem_queue *semsleeping;
/* CPU-specific state of this task */
	struct thread_struct thread;
/* filesystem information */
	struct fs_struct *fs;
/* open file information */
	struct files_struct *files;
/* namespace */
	struct namespace *namespace;
/* signal handlers */
	spinlock_t sigmask_lock;	/* Protects signal and blocked */
	struct signal_struct *sig;

	sigset_t blocked;
	struct sigpending pending;

	unsigned long sas_ss_sp;
	size_t sas_ss_size;
	int (*notifier)(void *priv);
	void *notifier_data;
	sigset_t *notifier_mask;

	/* TUX state */
	void *tux_info;
	void (*tux_exit)(void);
	
/* Thread group tracking */
   	u32 parent_exec_id;
   	u32 self_exec_id;
/* Protection of (de-)allocation: mm, files, fs, tty */
	spinlock_t alloc_lock;

/* journalling filesystem info */
	void *journal_info;
};

/*
 * Per process flags
 */
#define PF_EXITING	(1UL<<0)	/* getting shut down */
#define PF_FORKNOEXEC	(1UL<<1)	/* forked but didn't exec */
#define PF_SUPERPRIV	(1UL<<2)	/* used super-user privileges */
#define PF_DUMPCORE	(1UL<<3)	/* dumped core */
#define PF_SIGNALED	(1UL<<4)	/* killed by a signal */
#define PF_MEMALLOC	(1UL<<5)	/* Allocating memory */
#define PF_USEDFPU	(1UL<<6)	/* task used FPU this quantum (SMP) */
#define PF_ATOMICALLOC	(1UL<<7)	/* do not block during memalloc */
#define PF_FREE_PAGES	(1UL<<8)	/* per process page freeing */
#define PF_NOIO		(1UL<<9)	/* avoid generating further I/O */
#define PF_FSTRANS	(1UL<<10)	/* inside a filesystem transaction */

/*
 * Ptrace flags
 */

#define PT_PTRACED	0x00000001
#define PT_TRACESYS	0x00000002
#define PT_DTRACE	0x00000004	/* delayed trace (used on m68k, i386) */
#define PT_TRACESYSGOOD	0x00000008
#define PT_PTRACE_CAP	0x00000010	/* ptracer can follow suid-exec */

/*
 * Limit the stack by to some sane default: root can always
 * increase this limit if needed..  8MB seems reasonable.
 */
#define _STK_LIM	(8*1024*1024)

#if CONFIG_SMP
extern void set_cpus_allowed(task_t *p, unsigned long new_mask);
#else
#define set_cpus_allowed(p, new_mask)	do { } while (0)
#endif

extern void set_user_nice(task_t *p, long nice);
extern int task_prio(task_t *p);
extern int task_nice(task_t *p);

asmlinkage long sys_sched_yield(void);
#define yield()	sys_sched_yield()

/*
 * The default (Linux) execution domain.
 */