arch/riscv/include/asm/current.h

   1 /*
   2  * Based on arm/arm64/include/asm/current.h
   3  *
   4  * Copyright (C) 2016 ARM
   5  * Copyright (C) 2017 SiFive
   6  *
   7  *   This program is free software; you can redistribute it and/or
   8  *   modify it under the terms of the GNU General Public License
   9  *   as published by the Free Software Foundation, version 2.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  */
  16
  17
  18 #ifndef __ASM_CURRENT_H
  19 #define __ASM_CURRENT_H
  20
  21 #include <linux/bug.h>
  22 #include <linux/compiler.h>
  23
  24 #ifndef __ASSEMBLY__
  25
  26 struct task_struct;
  27
  28 /*
  29  * This only works because "struct thread_info" is at offset 0 from "struct
  30  * task_struct".  This constraint seems to be necessary on other architectures
  31  * as well, but __switch_to enforces it.  We can't check TASK_TI here because
  32  * <asm/asm-offsets.h> includes this, and I can't get the definition of "struct
  33  * task_struct" here due to some header ordering problems.
  34  */
  35 static __always_inline struct task_struct *get_current(void)
  36 {
  37         register struct task_struct *tp __asm__("tp");
  38         return tp;
  39 }
  40
  41 #define current get_current()
  42
  43 #endif /* __ASSEMBLY__ */
  44
  45 #endif /* __ASM_CURRENT_H */