LXR linux/include/linux/thread

   1/* thread_info.h: common low-level thread information accessors
   2 *
   3 * Copyright (C) 2002  David Howells (dhowells@redhat.com)
   4 * - Incorporating suggestions made by Linus Torvalds
   5 */
   6
   7#ifndef _LINUX_THREAD_INFO_H
   8#define _LINUX_THREAD_INFO_H
   9
  10#include <linux/types.h>
  11#include <linux/bug.h>
  12
  13struct timespec;
  14struct compat_timespec;
  15
  16/*
  17 * System call restart block.
  18 */
  19struct restart_block {
  20        long (*fn)(struct restart_block *);
  21        union {
  22                /* For futex_wait and futex_wait_requeue_pi */
  23                struct {
  24                        u32 __user *uaddr;
  25                        u32 val;
  26                        u32 flags;
  27                        u32 bitset;
  28                        u64 time;
  29                        u32 __user *uaddr2;
  30                } futex;
  31                /* For nanosleep */
  32                struct {
  33                        clockid_t clockid;
  34                        struct timespec __user *rmtp;
  35#ifdef CONFIG_COMPAT
  36                        struct compat_timespec __user *compat_rmtp;
  37#endif
  38                        u64 expires;
  39                } nanosleep;
  40                /* For poll */
  41                struct {
  42                        struct pollfd __user *ufds;
  43                        int nfds;
  44                        int has_timeout;
  45                        unsigned long tv_sec;
  46                        unsigned long tv_nsec;
  47                } poll;
  48        };
  49};
  50
  51extern long do_no_restart_syscall(struct restart_block *parm);
  52
  53#include <linux/bitops.h>
  54#include <asm/thread_info.h>
  55
  56#ifdef __KERNEL__
  57
  58#ifdef CONFIG_DEBUG_STACK_USAGE
  59# define THREADINFO_GFP         (GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO)
  60#else
  61# define THREADINFO_GFP         (GFP_KERNEL | __GFP_NOTRACK)
  62#endif
  63
  64#define THREADINFO_GFP_ACCOUNTED (THREADINFO_GFP | __GFP_KMEMCG)
  65
  66/*
  67 * flag set/clear/test wrappers
  68 * - pass TIF_xxxx constants to these functions
  69 */
  70
  71static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
  72{
  73        set_bit(flag, (unsigned long *)&ti->flags);
  74}
  75
  76static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
  77{
  78        clear_bit(flag, (unsigned long *)&ti->flags);
  79}
  80
  81static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
  82{
  83        return test_and_set_bit(flag, (unsigned long *)&ti->flags);
  84}
  85
  86static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
  87{
  88        return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
  89}
  90
  91static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
  92{
  93        return test_bit(flag, (unsigned long *)&ti->flags);
  94}
  95
  96#define set_thread_flag(flag) \
  97        set_ti_thread_flag(current_thread_info(), flag)
  98#define clear_thread_flag(flag) \
  99        clear_ti_thread_flag(current_thread_info(), flag)
 100#define test_and_set_thread_flag(flag) \
 101        test_and_set_ti_thread_flag(current_thread_info(), flag)
 102#define test_and_clear_thread_flag(flag) \
 103        test_and_clear_ti_thread_flag(current_thread_info(), flag)
 104#define test_thread_flag(flag) \
 105        test_ti_thread_flag(current_thread_info(), flag)
 106
 107#define set_need_resched()      set_thread_flag(TIF_NEED_RESCHED)
 108#define clear_need_resched()    clear_thread_flag(TIF_NEED_RESCHED)
 109
 110#if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK
 111/*
 112 * An arch can define its own version of set_restore_sigmask() to get the
 113 * job done however works, with or without TIF_RESTORE_SIGMASK.
 114 */
 115#define HAVE_SET_RESTORE_SIGMASK        1
 116
 117/**
 118 * set_restore_sigmask() - make sure saved_sigmask processing gets done
 119 *
 120 * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
 121 * will run before returning to user mode, to process the flag.  For
 122 * all callers, TIF_SIGPENDING is already set or it's no harm to set
 123 * it.  TIF_RESTORE_SIGMASK need not be in the set of bits that the
 124 * arch code will notice on return to user mode, in case those bits
 125 * are scarce.  We set TIF_SIGPENDING here to ensure that the arch
 126 * signal code always gets run when TIF_RESTORE_SIGMASK is set.
 127 */
 128static inline void set_restore_sigmask(void)
 129{
 130        set_thread_flag(TIF_RESTORE_SIGMASK);
 131        WARN_ON(!test_thread_flag(TIF_SIGPENDING));
 132}
 133static inline void clear_restore_sigmask(void)
 134{
 135        clear_thread_flag(TIF_RESTORE_SIGMASK);
 136}
 137static inline bool test_restore_sigmask(void)
 138{
 139        return test_thread_flag(TIF_RESTORE_SIGMASK);
 140}
 141static inline bool test_and_clear_restore_sigmask(void)
 142{
 143        return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
 144}
 145#endif  /* TIF_RESTORE_SIGMASK && !HAVE_SET_RESTORE_SIGMASK */
 146
 147#ifndef HAVE_SET_RESTORE_SIGMASK
 148#error "no set_restore_sigmask() provided and default one won't work"
 149#endif
 150
 151#endif  /* __KERNEL__ */
 152
 153#endif /* _LINUX_THREAD_INFO_H */
 154