Re: [PATCH v1 0/4] Support native debug icount trigger

[Alistair Francis]

On Thu, Oct 13, 2022 at 4:34 PM LIU Zhiwei <zhiwei_liu@linux.alibaba.com> wrote:
>
> icount trigger set an instruction count. After one instruction retired,
> the count will be decreased by 1. If the count decreased to 0, the icount
> trigger will fire.
>
> icount trigger is needed by single step ptrace system call and the native
> GDB.
>
> In this patch set, change the translation when icount trigger enabled in the
> way that instruction executes one by one. After executing one instruction,
> call a helper function to decrease the count for itrigger.
>
>
> It also provides an accelebrated way. If QEMU executes with -icount parameter,
> itrigger is simulated by a timer with the count in itrigger as the deadline.
>
> Note the count in itrigger will only decrease when the priviledge matches, 
> which
> is also processed in this patch set.
>
>
> After merging this patch set, QEMU will support type2/type6 trigger(needed by
> breakpoint and watchpoint) and icount trigger(needed by single step),
> which is enough for a PoC of native debug.
>
> LIU Zhiwei (4):
>   target/riscv: Add itrigger support when icount is not enabled
>   target/riscv: Add itrigger support when icount is enabled
>   target/riscv: Enable native debug itrigger
>   target/riscv: Add itrigger_enabled field to CPURISCVState

Thanks!

Applied to riscv-to-apply.next

Alistair

>
>  target/riscv/cpu.h                            |   5 +
>  target/riscv/cpu_helper.c                     |   8 +
>  target/riscv/debug.c                          | 205 ++++++++++++++++++
>  target/riscv/debug.h                          |  13 ++
>  target/riscv/helper.h                         |   2 +
>  .../riscv/insn_trans/trans_privileged.c.inc   |   4 +-
>  target/riscv/insn_trans/trans_rvi.c.inc       |   8 +-
>  target/riscv/insn_trans/trans_rvv.c.inc       |   4 +-
>  target/riscv/machine.c                        |  15 ++
>  target/riscv/translate.c                      |  33 ++-
>  10 files changed, 286 insertions(+), 11 deletions(-)
>
> --
> 2.17.1
>
>