include/linux/thread_info.h

   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
  13 struct timespec;
  14 struct compat_timespec;
  15
  16 /*
  17  * System call restart block.
  18  */
  19 struct 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
  51 extern 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
  71 static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
  72 {
  73         set_bit(flag, (unsigned long *)&ti->flags);
  74 }
  75
  76 static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
  77 {
  78         clear_bit(flag, (unsigned long *)&ti->flags);
  79 }
  80
  81 static 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
  86 static 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
  91 static 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 static inline __deprecated void set_need_resched(void)
 108 {
 109         /*
 110          * Use of this function in deprecated.
 111          *
 112          * As of this writing there are only a few users in the DRM tree left
 113          * all of which are wrong and can be removed without causing too much
 114          * grief.
 115          *
 116          * The DRM people are aware and are working on removing the last few
 117          * instances.
 118          */
 119 }
 120
 121 #define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
 122
 123 #if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK
 124 /*
 125  * An arch can define its own version of set_restore_sigmask() to get the
 126  * job done however works, with or without TIF_RESTORE_SIGMASK.
 127  */
 128 #define HAVE_SET_RESTORE_SIGMASK        1
 129
 130 /**
 131  * set_restore_sigmask() - make sure saved_sigmask processing gets done
 132  *
 133  * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
 134  * will run before returning to user mode, to process the flag.  For
 135  * all callers, TIF_SIGPENDING is already set or it's no harm to set
 136  * it.  TIF_RESTORE_SIGMASK need not be in the set of bits that the
 137  * arch code will notice on return to user mode, in case those bits
 138  * are scarce.  We set TIF_SIGPENDING here to ensure that the arch
 139  * signal code always gets run when TIF_RESTORE_SIGMASK is set.
 140  */
 141 static inline void set_restore_sigmask(void)
 142 {
 143         set_thread_flag(TIF_RESTORE_SIGMASK);
 144         WARN_ON(!test_thread_flag(TIF_SIGPENDING));
 145 }
 146 static inline void clear_restore_sigmask(void)
 147 {
 148         clear_thread_flag(TIF_RESTORE_SIGMASK);
 149 }
 150 static inline bool test_restore_sigmask(void)
 151 {
 152         return test_thread_flag(TIF_RESTORE_SIGMASK);
 153 }
 154 static inline bool test_and_clear_restore_sigmask(void)
 155 {
 156         return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
 157 }
 158 #endif  /* TIF_RESTORE_SIGMASK && !HAVE_SET_RESTORE_SIGMASK */
 159
 160 #ifndef HAVE_SET_RESTORE_SIGMASK
 161 #error "no set_restore_sigmask() provided and default one won't work"
 162 #endif
 163
 164 #endif  /* __KERNEL__ */
 165
 166 #endif /* _LINUX_THREAD_INFO_H */