[PATCH v7 3/3] riscv: store percpu offset into thread_info

[bot+bpf-ci at kernel.org]

> diff --git a/arch/riscv/include/asm/asm.h b/arch/riscv/include/asm/asm.h
> index e9e8ba83e632..137a49488325 100644
> --- a/arch/riscv/include/asm/asm.h
> +++ b/arch/riscv/include/asm/asm.h
> @@ -91,11 +91,7 @@
>
>  #ifdef CONFIG_SMP
>  .macro asm_per_cpu dst sym tmp
> -	lw    \tmp, TASK_TI_CPU_NUM(tp)
> -	slli  \tmp, \tmp, RISCV_LGPTR
> -	la    \dst, __per_cpu_offset
> -	add   \dst, \dst, \tmp
> -	REG_L \tmp, 0(\dst)
> +	REG_L \tmp, TASK_TI_PCPU_OFFSET(tp)
>  	la    \dst, \sym
>  	add   \dst, \dst, \tmp
>  .endm

This isn't a bug, but asm_per_cpu was the only reader of TASK_TI_CPU_NUM,
and it now loads TASK_TI_PCPU_OFFSET(tp) instead.

> diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c
> index af827448a609..fbf53b66b0e0 100644
> --- a/arch/riscv/kernel/asm-offsets.c
> +++ b/arch/riscv/kernel/asm-offsets.c
> @@ -38,6 +38,7 @@ void asm_offsets(void)
>  	OFFSET(TASK_THREAD_SUM, task_struct, thread.sum);
>
>  	OFFSET(TASK_TI_CPU, task_struct, thread_info.cpu);
> +	OFFSET(TASK_TI_PCPU_OFFSET, task_struct, thread_info.pcpu_offset);
>  	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);

A tree-wide search now finds TASK_TI_CPU_NUM only at its definition in
asm_offsets():

	OFFSET(TASK_TI_CPU_NUM, task_struct, thread_info.cpu);

with no remaining users (TASK_TI_CPU is a separate symbol still referenced
by entry.S).  Could this OFFSET() line be dropped as well?


---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md

CI run summary: https://github.com/kernel-patches/bpf/actions/runs/28562450933