sched.h

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/* Definitions of constants and data structure for POSIX 1003.1b-1993
   scheduling interface.
   Copyright (C) 1996-1999,2001-2003,2005,2006,2007
   Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#ifndef __need_schedparam

#ifndef _SCHED_H
# error "Never include <bits/sched.h> directly; use <sched.h> instead."
#endif


/* Scheduling algorithms.  */
#define SCHED_OTHER	0
#define SCHED_FIFO	1
#define SCHED_RR	2
#ifdef __USE_GNU
# define SCHED_BATCH	3
#endif

#ifdef __USE_MISC
/* 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 shared.  */
# define CLONE_PTRACE  0x00002000 /* Set if tracing continues on the child.  */
# 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 /* Set to add to same thread group.  */
# define CLONE_NEWNS   0x00020000 /* Set to create new namespace.  */
# define CLONE_SYSVSEM 0x00040000 /* Set to shared SVID SEM_UNDO semantics.  */
# define CLONE_SETTLS  0x00080000 /* Set TLS info.  */
# define CLONE_PARENT_SETTID 0x00100000 /* Store TID in userlevel buffer
					   before MM copy.  */
# define CLONE_CHILD_CLEARTID 0x00200000 /* Register exit futex and memory
					    location to clear.  */
# define CLONE_DETACHED 0x00400000 /* Create clone detached.  */
# define CLONE_UNTRACED 0x00800000 /* Set if the tracing process can't
				      force CLONE_PTRACE on this clone.  */
# define CLONE_CHILD_SETTID 0x01000000 /* Store TID in userlevel buffer in
					  the child.  */
# define CLONE_STOPPED	0x02000000 /* Start in stopped state.  */
#endif

/* The official definition.  */
struct sched_param
  {
    int __sched_priority;
  };

__BEGIN_DECLS

#ifdef __USE_MISC
/* Clone current process.  */
extern int clone (int (*__fn) (void *__arg), void *__child_stack,
		  int __flags, void *__arg, ...) __THROW;

/* Unshare the specified resources.  */
extern int unshare (int __flags) __THROW;

/* Get index of currently used CPU.  */
extern int sched_getcpu (void) __THROW;
#endif

__END_DECLS

#endif	/* need schedparam */

#if !defined __defined_schedparam \
    && (defined __need_schedparam || defined _SCHED_H)
# define __defined_schedparam	1
/* Data structure to describe a process' schedulability.  */
struct __sched_param
  {
    int __sched_priority;
  };
# undef __need_schedparam
#endif


#if defined _SCHED_H && !defined __cpu_set_t_defined
# define __cpu_set_t_defined
/* Size definition for CPU sets.  */
# define __CPU_SETSIZE	1024
# define __NCPUBITS	(8 * sizeof (__cpu_mask))

/* Type for array elements in 'cpu_set'.  */
typedef unsigned long int __cpu_mask;

/* Basic access functions.  */
# define __CPUELT(cpu)	((cpu) / __NCPUBITS)
# define __CPUMASK(cpu)	((__cpu_mask) 1 << ((cpu) % __NCPUBITS))

/* Data structure to describe CPU mask.  */
typedef struct
{
  __cpu_mask __bits[__CPU_SETSIZE / __NCPUBITS];
} cpu_set_t;

/* Access functions for CPU masks.  */
# define __CPU_ZERO(cpusetp) \
  do {									      \
    unsigned int __i;							      \
    cpu_set_t *__arr = (cpusetp);					      \
    for (__i = 0; __i < sizeof (cpu_set_t) / sizeof (__cpu_mask); ++__i)      \
      __arr->__bits[__i] = 0;						      \
  } while (0)
# define __CPU_SET(cpu, cpusetp) \
  ((cpusetp)->__bits[__CPUELT (cpu)] |= __CPUMASK (cpu))
# define __CPU_CLR(cpu, cpusetp) \
  ((cpusetp)->__bits[__CPUELT (cpu)] &= ~__CPUMASK (cpu))
# define __CPU_ISSET(cpu, cpusetp) \
  (((cpusetp)->__bits[__CPUELT (cpu)] & __CPUMASK (cpu)) != 0)
extern int __sched_cpucount (size_t __setsize, cpu_set_t *__setp) __THROW;
# define __CPU_COUNT(cpusetp) \
  __sched_cpucount (sizeof (cpu_set_t), cpusetp)
#endif