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/*
  65 * flag set/clear/test wrappers
  66 * - pass TIF_xxxx constants to these functions
  67 */
  68
  69static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
  70{
  71        set_bit(flag, (unsigned long *)&ti->flags);
  72}
  73
  74static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
  75{
  76        clear_bit(flag, (unsigned long *)&ti->flags);
  77}
  78
  79static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
  80{
  81        return test_and_set_bit(flag, (unsigned long *)&ti->flags);
  82}
  83
  84static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
  85{
  86        return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
  87}
  88
  89static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
  90{
  91        return test_bit(flag, (unsigned long *)&ti->flags);
  92}
  93
  94#define set_thread_flag(flag) \
  95        set_ti_thread_flag(current_thread_info(), flag)
  96#define clear_thread_flag(flag) \
  97        clear_ti_thread_flag(current_thread_info(), flag)
  98#define test_and_set_thread_flag(flag) \
  99        test_and_set_ti_thread_flag(current_thread_info(), flag)
 100#define test_and_clear_thread_flag(flag) \
 101        test_and_clear_ti_thread_flag(current_thread_info(), flag)
 102#define test_thread_flag(flag) \
 103        test_ti_thread_flag(current_thread_info(), flag)
 104
 105#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
 106
 107#if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK
 108/*
 109 * An arch can define its own version of set_restore_sigmask() to get the
 110 * job done however works, with or without TIF_RESTORE_SIGMASK.
 111 */
 112#define HAVE_SET_RESTORE_SIGMASK        1
 113
 114/**
 115 * set_restore_sigmask() - make sure saved_sigmask processing gets done
 116 *
 117 * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
 118 * will run before returning to user mode, to process the flag.  For
 119 * all callers, TIF_SIGPENDING is already set or it's no harm to set
 120 * it.  TIF_RESTORE_SIGMASK need not be in the set of bits that the
 121 * arch code will notice on return to user mode, in case those bits
 122 * are scarce.  We set TIF_SIGPENDING here to ensure that the arch
 123 * signal code always gets run when TIF_RESTORE_SIGMASK is set.
 124 */
 125static inline void set_restore_sigmask(void)
 126{
 127        set_thread_flag(TIF_RESTORE_SIGMASK);
 128        WARN_ON(!test_thread_flag(TIF_SIGPENDING));
 129}
 130static inline void clear_restore_sigmask(void)
 131{
 132        clear_thread_flag(TIF_RESTORE_SIGMASK);
 133}
 134static inline bool test_restore_sigmask(void)
 135{
 136        return test_thread_flag(TIF_RESTORE_SIGMASK);
 137}
 138static inline bool test_and_clear_restore_sigmask(void)
 139{
 140        return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
 141}
 142#endif  /* TIF_RESTORE_SIGMASK && !HAVE_SET_RESTORE_SIGMASK */
 143
 144#ifndef HAVE_SET_RESTORE_SIGMASK
 145#error "no set_restore_sigmask() provided and default one won't work"
 146#endif
 147
 148#endif  /* __KERNEL__ */
 149
 150#endif /* _LINUX_THREAD_INFO_H */
 151