1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _ASM_X86_CURRENT_H 3#define _ASM_X86_CURRENT_H 4 5#include <linux/build_bug.h> 6#include <linux/compiler.h> 7 8#ifndef __ASSEMBLY__ 9 10#include <linux/cache.h> 11#include <asm/percpu.h> 12 13struct task_struct; 14 15struct pcpu_hot { 16 union { 17 struct { 18 struct task_struct *current_task; 19 int preempt_count; 20 int cpu_number; 21#ifdef CONFIG_MITIGATION_CALL_DEPTH_TRACKING 22 u64 call_depth; 23#endif 24 unsigned long top_of_stack; 25 void *hardirq_stack_ptr; 26 u16 softirq_pending; 27#ifdef CONFIG_X86_64 28 bool hardirq_stack_inuse; 29#else 30 void *softirq_stack_ptr; 31#endif 32 }; 33 u8 pad[64]; 34 }; 35}; 36static_assert(sizeof(struct pcpu_hot) == 64); 37 38DECLARE_PER_CPU_ALIGNED(struct pcpu_hot, pcpu_hot); 39 40/* const-qualified alias to pcpu_hot, aliased by linker. */ 41DECLARE_PER_CPU_ALIGNED(const struct pcpu_hot __percpu_seg_override, 42 const_pcpu_hot); 43 44static __always_inline struct task_struct *get_current(void) 45{ 46 if (IS_ENABLED(CONFIG_USE_X86_SEG_SUPPORT)) 47 return this_cpu_read_const(const_pcpu_hot.current_task); 48 49 return this_cpu_read_stable(pcpu_hot.current_task); 50} 51 52#define current get_current() 53 54#endif /* __ASSEMBLY__ */ 55 56#endif /* _ASM_X86_CURRENT_H */ 57