diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index d5c8ac81ce11..e1317b7c4525 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -42,6 +42,7 @@ struct thread_info { void *scs_base; void *scs_sp; #endif + u32 cpu; }; #define thread_saved_pc(tsk) \ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 2124357c2075..6d0c3afd36b8 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -28,8 +28,8 @@ int main(void) { DEFINE(TSK_ACTIVE_MM, offsetof(struct task_struct, active_mm)); - DEFINE(TSK_CPU, offsetof(struct task_struct, cpu)); BLANK(); + DEFINE(TSK_TI_CPU, offsetof(struct task_struct, thread_info.cpu)); DEFINE(TSK_TI_FLAGS, offsetof(struct task_struct, thread_info.flags)); DEFINE(TSK_TI_PREEMPT, offsetof(struct task_struct, thread_info.preempt_count)); #ifdef CONFIG_ARM64_SW_TTBR0_PAN diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 17962452e31d..6a98f1a38c29 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -412,7 +412,7 @@ SYM_FUNC_END(__create_page_tables) scs_load \tsk adr_l \tmp1, __per_cpu_offset - ldr w\tmp2, [\tsk, #TSK_CPU] + ldr w\tmp2, [\tsk, #TSK_TI_CPU] ldr \tmp1, [\tmp1, \tmp2, lsl #3] set_this_cpu_offset \tmp1 .endm diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index aa6808e70647..54cad1faa5d0 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -446,17 +446,6 @@ else endif endif -ifdef CONFIG_SMP -ifdef CONFIG_PPC32 -prepare: task_cpu_prepare - -PHONY += task_cpu_prepare -task_cpu_prepare: prepare0 - $(eval KBUILD_CFLAGS += -D_TASK_CPU=$(shell awk '{if ($$2 == "TASK_CPU") print $$3;}' include/generated/asm-offsets.h)) - -endif # CONFIG_PPC32 -endif # CONFIG_SMP - PHONY += checkbin # Check toolchain versions: # - gcc-4.6 is the minimum kernel-wide version so nothing required. diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h index 7ef1cd8168a0..007332a4a732 100644 --- a/arch/powerpc/include/asm/smp.h +++ b/arch/powerpc/include/asm/smp.h @@ -87,22 +87,7 @@ int is_cpu_dead(unsigned int cpu); /* 32-bit */ extern int smp_hw_index[]; -/* - * This is particularly ugly: it appears we can't actually get the definition - * of task_struct here, but we need access to the CPU this task is running on. - * Instead of using task_struct we're using _TASK_CPU which is extracted from - * asm-offsets.h by kbuild to get the current processor ID. - * - * This also needs to be safeguarded when building asm-offsets.s because at - * that time _TASK_CPU is not defined yet. It could have been guarded by - * _TASK_CPU itself, but we want the build to fail if _TASK_CPU is missing - * when building something else than asm-offsets.s - */ -#ifdef GENERATING_ASM_OFFSETS -#define raw_smp_processor_id() (0) -#else -#define raw_smp_processor_id() (*(unsigned int *)((void *)current + _TASK_CPU)) -#endif +#define raw_smp_processor_id() (current_thread_info()->cpu) #define hard_smp_processor_id() (smp_hw_index[smp_processor_id()]) static inline int get_hard_smp_processor_id(int cpu) diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h index b4ec6c7dd72e..5725029aaa29 100644 --- a/arch/powerpc/include/asm/thread_info.h +++ b/arch/powerpc/include/asm/thread_info.h @@ -47,6 +47,9 @@ struct thread_info { int preempt_count; /* 0 => preemptable, <0 => BUG */ +#ifdef CONFIG_SMP + unsigned int cpu; +#endif unsigned long local_flags; /* private flags for thread */ #ifdef CONFIG_LIVEPATCH unsigned long *livepatch_sp; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index e563d3222d69..cc05522f50bf 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -9,8 +9,6 @@ * #defines from the assembly-language output. */ -#define GENERATING_ASM_OFFSETS /* asm/smp.h */ - #include #include #include @@ -93,7 +91,7 @@ int main(void) #endif /* CONFIG_PPC64 */ OFFSET(TASK_STACK, task_struct, stack); #ifdef CONFIG_SMP - OFFSET(TASK_CPU, task_struct, cpu); + OFFSET(TASK_CPU, task_struct, thread_info.cpu); #endif #ifdef CONFIG_LIVEPATCH diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 605bab448f84..f7440f4eca2e 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -1223,7 +1223,7 @@ static void cpu_idle_thread_init(unsigned int cpu, struct task_struct *idle) paca_ptrs[cpu]->kstack = (unsigned long)task_stack_page(idle) + THREAD_SIZE - STACK_FRAME_OVERHEAD; #endif - idle->cpu = cpu; + task_thread_info(idle)->cpu = cpu; secondary_current = current_set[cpu] = idle; } diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c index 90f8ce64fa6f..478d9f02dab5 100644 --- a/arch/riscv/kernel/asm-offsets.c +++ b/arch/riscv/kernel/asm-offsets.c @@ -33,7 +33,6 @@ void asm_offsets(void) OFFSET(TASK_TI_PREEMPT_COUNT, task_struct, thread_info.preempt_count); OFFSET(TASK_TI_KERNEL_SP, task_struct, thread_info.kernel_sp); OFFSET(TASK_TI_USER_SP, task_struct, thread_info.user_sp); - OFFSET(TASK_TI_CPU, task_struct, thread_info.cpu); OFFSET(TASK_THREAD_F0, task_struct, thread.fstate.f[0]); OFFSET(TASK_THREAD_F1, task_struct, thread.fstate.f[1]); diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 64236f7efde5..ed29e9c8f660 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -543,11 +543,6 @@ ENTRY(__switch_to) REG_L s9, TASK_THREAD_S9_RA(a4) REG_L s10, TASK_THREAD_S10_RA(a4) REG_L s11, TASK_THREAD_S11_RA(a4) - /* Swap the CPU entry around. */ - lw a3, TASK_TI_CPU(a0) - lw a4, TASK_TI_CPU(a1) - sw a3, TASK_TI_CPU(a1) - sw a4, TASK_TI_CPU(a0) /* The offset of thread_info in task_struct is zero. */ move tp, a1 ret diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 52c5ff9804c5..25ec50573957 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -318,7 +318,6 @@ clear_bss_done: call setup_trap_vector /* Restore C environment */ la tp, init_task - sw zero, TASK_TI_CPU(tp) la sp, init_thread_union + THREAD_SIZE #ifdef CONFIG_KASAN diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h index e6674796aa6f..b2ffcb4fe000 100644 --- a/arch/s390/include/asm/thread_info.h +++ b/arch/s390/include/asm/thread_info.h @@ -37,6 +37,7 @@ struct thread_info { unsigned long flags; /* low level flags */ unsigned long syscall_work; /* SYSCALL_WORK_ flags */ + unsigned int cpu; /* current CPU */ }; /* diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index cf132663c219..ebec69c35e95 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -57,6 +57,9 @@ struct thread_info { unsigned long flags; /* low level flags */ unsigned long syscall_work; /* SYSCALL_WORK_ flags */ u32 status; /* thread synchronous flags */ +#ifdef CONFIG_SMP + u32 cpu; /* current CPU */ +#endif }; #define INIT_THREAD_INFO(tsk) \ diff --git a/include/linux/sched.h b/include/linux/sched.h index f44e14c43b74..6f6f8f340a0f 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -750,10 +750,6 @@ struct task_struct { #ifdef CONFIG_SMP int on_cpu; struct __call_single_node wake_entry; -#ifdef CONFIG_THREAD_INFO_IN_TASK - /* Current CPU: */ - unsigned int cpu; -#endif unsigned int wakee_flips; unsigned long wakee_flip_decay_ts; struct task_struct *last_wakee; @@ -1886,10 +1882,7 @@ extern struct thread_info init_thread_info; extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; #ifdef CONFIG_THREAD_INFO_IN_TASK -static inline struct thread_info *task_thread_info(struct task_struct *task) -{ - return &task->thread_info; -} +# define task_thread_info(task) (&(task)->thread_info) #elif !defined(__HAVE_THREAD_FUNCTIONS) # define task_thread_info(task) ((struct thread_info *)(task)->stack) #endif @@ -2133,11 +2126,7 @@ static __always_inline bool need_resched(void) static inline unsigned int task_cpu(const struct task_struct *p) { -#ifdef CONFIG_THREAD_INFO_IN_TASK - return READ_ONCE(p->cpu); -#else return READ_ONCE(task_thread_info(p)->cpu); -#endif } extern void set_task_cpu(struct task_struct *p, unsigned int cpu); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 56ff343d4119..7f1612d26c18 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1912,11 +1912,7 @@ static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) * per-task data have been completed by this moment. */ smp_wmb(); -#ifdef CONFIG_THREAD_INFO_IN_TASK - WRITE_ONCE(p->cpu, cpu); -#else WRITE_ONCE(task_thread_info(p)->cpu, cpu); -#endif p->wake_cpu = cpu; #endif }