Re: [PATCH -next v5 00/22] arm64: entry: Convert to generic entry

Jinjie Ruan
2025-02-08T01:17:01Z

On 2024/12/6 18:17, Jinjie Ruan wrote:
> Currently, x86, Riscv, Loongarch use the generic entry. Convert arm64
> to use the generic entry infrastructure from kernel/entry/*. The generic
> entry makes maintainers' work easier and codes more elegant, which aslo
> removed a lot of duplicate code.
>
> The main steps are as follows:
> - Make arm64 easier to use irqentry_enter/exit().
> - Make arm64 closer to the PREEMPT_DYNAMIC code of generic entry.
> - Split generic entry into generic irq entry and generic syscall to
> make the single patch more concentrated in switching to one thing.
> - Switch to generic irq entry.
> - Make arm64 closer to the generic syscall code.
> - Switch to generic entry completely.
>
> Changes in v5:
> - Not change arm32 and keep inerrupts_enabled() macro for gicv3 driver.
> - Move irqentry_state definition into arch/arm64/kernel/entry-common.c.
> - Avoid removing the __enter_from_*() and __exit_to_*() wrappers.
> - Update "irqentry_state_t ret/irq_state" to "state"
> to keep it consistently.
> - Use generic irq entry header for PREEMPT_DYNAMIC after split
> the generic entry.
> - Also refactor the ARM64 syscall code.
> - Introduce arch_ptrace_report_syscall_entry/exit(), instead of
> arch_pre/post_report_syscall_entry/exit() to simplify code.
> - Make the syscall patches clear separation.
> - Update the commit message.

Gentle Ping.

>
> Changes in v4:
> - Rework/cleanup split into a few patches as Mark suggested.
> - Replace interrupts_enabled() macro with regs_irqs_disabled(), instead
> of left it here.
> - Remove rcu and lockdep state in pt_regs by using temporary
> irqentry_state_t as Mark suggested.
> - Remove some unnecessary intermediate functions to make it clear.
> - Rework preempt irq and PREEMPT_DYNAMIC code
> to make the switch more clear.
> - arch_prepare_*_entry/exit() -> arch_pre_*_entry/exit().
> - Expand the arch functions comment.
> - Make arch functions closer to its caller.
> - Declare saved_reg in for block.
> - Remove arch_exit_to_kernel_mode_prepare(), arch_enter_from_kernel_mode().
> - Adjust "Add few arch functions to use generic entry" patch to be
> the penultimate.
> - Update the commit message.
> - Add suggested-by.
>
> Changes in v3:
> - Test the MTE test cases.
> - Handle forget_syscall() in arch_post_report_syscall_entry()
> - Make the arch funcs not use __weak as Thomas suggested, so move
> the arch funcs to entry-common.h, and make arch_forget_syscall() folded
> in arch_post_report_syscall_entry() as suggested.
> - Move report_single_step() to thread_info.h for arm64
> - Change __always_inline() to inline, add inline for the other arch funcs.
> - Remove unused signal.h for entry-common.h.
> - Add Suggested-by.
> - Update the commit message.
>
> Changes in v2:
> - Add tested-by.
> - Fix a bug that not call arch_post_report_syscall_entry() in
> syscall_trace_enter() if ptrace_report_syscall_entry() return not zero.
> - Refactor report_syscall().
> - Add comment for arch_prepare_report_syscall_exit().
> - Adjust entry-common.h header file inclusion to alphabetical order.
> - Update the commit message.
>
> Jinjie Ruan (22):
> arm64: ptrace: Replace interrupts_enabled() with regs_irqs_disabled()
> arm64: entry: Refactor the entry and exit for exceptions from EL1
> arm64: entry: Move arm64_preempt_schedule_irq() into
> __exit_to_kernel_mode()
> arm64: entry: Rework arm64_preempt_schedule_irq()
> arm64: entry: Use preempt_count() and need_resched() helper
> arm64: entry: Expand the need_irq_preemption() macro ahead
> arm64: entry: preempt_schedule_irq() only if PREEMPTION enabled
> arm64: entry: Use different helpers to check resched for
> PREEMPT_DYNAMIC
> entry: Split generic entry into irq and syscall
> entry: Add arch_irqentry_exit_need_resched() for arm64
> arm64: entry: Switch to generic IRQ entry
> arm64/ptrace: Split report_syscall() function
> arm64/ptrace: Refactor syscall_trace_enter()
> arm64/ptrace: Refactor syscall_trace_exit()
> arm64/ptrace: Refator el0_svc_common()
> entry: Make syscall_exit_to_user_mode_prepare() not static
> arm64/ptrace: Return early for ptrace_report_syscall_entry() error
> arm64/ptrace: Expand secure_computing() in place
> arm64/ptrace: Use syscall_get_arguments() heleper
> entry: Add arch_ptrace_report_syscall_entry/exit()
> entry: Add has_syscall_work() helepr
> arm64: entry: Convert to generic entry
>
> MAINTAINERS | 1 +
> arch/Kconfig | 8 +
> arch/arm64/Kconfig | 1 +
> arch/arm64/include/asm/daifflags.h | 2 +-
> arch/arm64/include/asm/entry-common.h | 134 +++++++++
> arch/arm64/include/asm/preempt.h | 2 -
> arch/arm64/include/asm/ptrace.h | 11 +-
> arch/arm64/include/asm/syscall.h | 6 +-
> arch/arm64/include/asm/thread_info.h | 23 +-
> arch/arm64/include/asm/xen/events.h | 2 +-
> arch/arm64/kernel/acpi.c | 2 +-
> arch/arm64/kernel/debug-monitors.c | 9 +-
> arch/arm64/kernel/entry-common.c | 377 ++++++++-----------------
> arch/arm64/kernel/ptrace.c | 90 ------
> arch/arm64/kernel/sdei.c | 2 +-
> arch/arm64/kernel/signal.c | 3 +-
> arch/arm64/kernel/syscall.c | 31 +-
> include/linux/entry-common.h | 384 +------------------------
> include/linux/irq-entry-common.h | 389 ++++++++++++++++++++++++++
> kernel/entry/Makefile | 3 +-
> kernel/entry/common.c | 176 ++----------
> kernel/entry/syscall-common.c | 198 +++++++++++++
> kernel/sched/core.c | 8 +-
> 23 files changed, 909 insertions(+), 953 deletions(-)
> create mode 100644 arch/arm64/include/asm/entry-common.h
> create mode 100644 include/linux/irq-entry-common.h
> create mode 100644 kernel/entry/syscall-common.c
>