From: Jisheng Zhang <jszhang@kernel.org> Date: Tue, 31 Oct 2023 22:35:20 +0800 Subject: [PATCH] riscv: add PREEMPT_AUTO support riscv has switched to GENERIC_ENTRY, so adding PREEMPT_AUTO is as simple as adding TIF_ARCH_RESCHED_LAZY related definitions and enabling HAVE_PREEMPT_AUTO. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/thread_info.h | 2 ++ 2 files changed, 3 insertions(+) Index: linux-6.8.2-rt10/arch/riscv/Kconfig =================================================================== @ linux-6.8.2-rt10/arch/riscv/Kconfig:145 @ config RISCV select HAVE_PERF_USER_STACK_DUMP select HAVE_POSIX_CPU_TIMERS_TASK_WORK select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL + select HAVE_PREEMPT_AUTO select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RETHOOK if !XIP_KERNEL select HAVE_RSEQ Index: linux-6.8.2-rt10/arch/riscv/include/asm/thread_info.h =================================================================== --- linux-6.8.2-rt10.orig/arch/riscv/include/asm/thread_info.h +++ linux-6.8.2-rt10/arch/riscv/include/asm/thread_info.h @ linux-6.8.2-rt10/arch/riscv/Kconfig:97 @ int arch_dup_task_struct(struct task_str * - pending work-to-be-done flags are in lowest half-word * - other flags in upper half-word(s) */ +#define TIF_ARCH_RESCHED_LAZY 0 /* Lazy rescheduling */ #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ #define TIF_SIGPENDING 2 /* signal pending */ #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ @ linux-6.8.2-rt10/arch/riscv/Kconfig:108 @ int arch_dup_task_struct(struct task_str #define TIF_32BIT 11 /* compat-mode 32bit process */ #define TIF_RISCV_V_DEFER_RESTORE 12 /* restore Vector before returing to user */ +#define _TIF_ARCH_RESCHED_LAZY (1 << TIF_ARCH_RESCHED_LAZY) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)