[PATCH v8 05/12] arm64: syscall: Rework el0_svc_common()

[Kevin Brodsky]

On 26/11/2025 08:14, Jinjie Ruan wrote:
> The generic syscall syscall_exit_work() has the following content:
>
> | audit_syscall_exit(regs)
> | trace_sys_exit(regs, ...)
> | ptrace_report_syscall_exit(regs, step)
>
> The generic syscall syscall_exit_to_user_mode_work() has
> the following form:
>
> | unsigned long work = READ_ONCE(current_thread_info()->syscall_work)
> | rseq_syscall()
> | if (unlikely(work & SYSCALL_WORK_EXIT))
> |	syscall_exit_work(regs, work)
>
> In preparation for moving arm64 over to the generic entry code,
> rework el0_svc_common() as below:
>
> - Rename syscall_trace_exit() to syscall_exit_work().
>
> - Add syscall_exit_to_user_mode_prepare() function to replace
>   the combination of read_thread_flags() and syscall_exit_work(),
>   also move the syscall exit check logic into it. Move has_syscall_work()
>   helper into asm/syscall.h for reuse.
>
> - As currently rseq_syscall() is always called and itself is controlled
>   by the CONFIG_DEBUG_RSEQ macro, so the CONFIG_DEBUG_RSEQ check
>   is removed.
>
> Signed-off-by: Jinjie Ruan <ruanjinjie at huawei.com>

Reviewed-by: Kevin Brodsky <kevin.brodsky at arm.com>