[PATCH v4 0/4] Add unwinder support

Qing Zhang posted 4 patches 5 days, 14 hours ago
arch/loongarch/Kconfig                  |   6 +
arch/loongarch/Kconfig.debug            |  28 ++++
arch/loongarch/include/asm/inst.h       |  52 +++++++
arch/loongarch/include/asm/processor.h  |   9 ++
arch/loongarch/include/asm/stacktrace.h |  22 +++
arch/loongarch/include/asm/switch_to.h  |  14 +-
arch/loongarch/include/asm/unwind.h     |  47 +++++++
arch/loongarch/kernel/Makefile          |   4 +
arch/loongarch/kernel/asm-offsets.c     |   2 +
arch/loongarch/kernel/process.c         |  91 ++++++++++++-
arch/loongarch/kernel/stacktrace.c      |  78 +++++++++++
arch/loongarch/kernel/switch.S          |   2 +
arch/loongarch/kernel/traps.c           |  24 ++--
arch/loongarch/kernel/unwind_guess.c    |  67 +++++++++
arch/loongarch/kernel/unwind_prologue.c | 173 ++++++++++++++++++++++++
15 files changed, 602 insertions(+), 17 deletions(-)
create mode 100644 arch/loongarch/include/asm/unwind.h
create mode 100644 arch/loongarch/kernel/stacktrace.c
create mode 100644 arch/loongarch/kernel/unwind_guess.c
create mode 100644 arch/loongarch/kernel/unwind_prologue.c
[PATCH v4 0/4] Add unwinder support
Posted by Qing Zhang 5 days, 14 hours ago
This series in order to add stacktrace support, Some upcoming features require
these changes, like trace, divide unwinder into guess unwinder and prologue
unwinder is to add new unwinders in the future.
eg:unwinder_frame, unwinder_orc .etc.

Three stages when we do unwind,
  1) unwind_start(), the prapare of unwinding, fill unwind_state.
  2) unwind_done(), judge whether the unwind process is finished or not.
  3) unwind_next_frame(), unwind the next frame.

you can test them by:
  1) echo t > /proc/sysrq-trigger
  2) cat /proc/*/stack
  3) ftrace: function graph
  4) uprobe: echo 1 > ./options/userstacktrace

Changes from v1 to v2:

- Add the judgment of the offset value of ra in the prologue.
  (Suggested by Youling).
- Create an inline function to check the sign bit, which is convenient
  for extending other types of immediates.  (Suggested by Jinyang).
- Fix sparse warning :
    arch/loongarch/include/asm/uaccess.h:232:32: sparse: sparse: incorrect
    type in argument 2 (different address spaces) @@     expected void const
    *from @@     got void const [noderef] __user *from @@
- Add USER_STACKTRACE support as a series.

Changes from v2 to v3:

- Move unwind_start definition and use location, remove #ifdef in unwind_state
  and use type instead of enable. (Suggested by Huacai).
- Separated fixes for uaccess.h. (Suggested by Huacai).

Changes from v3 to v4:

- Add get wchan implement. (Suggested by Huacai).

Qing Zhang (4):
  LoongArch: Add guess unwinder support
  LoongArch: Add prologue unwinder support
  LoongArch: Add stacktrace and get_wchan support
  LoongArch: Add USER_STACKTRACE support

 arch/loongarch/Kconfig                  |   6 +
 arch/loongarch/Kconfig.debug            |  28 ++++
 arch/loongarch/include/asm/inst.h       |  52 +++++++
 arch/loongarch/include/asm/processor.h  |   9 ++
 arch/loongarch/include/asm/stacktrace.h |  22 +++
 arch/loongarch/include/asm/switch_to.h  |  14 +-
 arch/loongarch/include/asm/unwind.h     |  47 +++++++
 arch/loongarch/kernel/Makefile          |   4 +
 arch/loongarch/kernel/asm-offsets.c     |   2 +
 arch/loongarch/kernel/process.c         |  91 ++++++++++++-
 arch/loongarch/kernel/stacktrace.c      |  78 +++++++++++
 arch/loongarch/kernel/switch.S          |   2 +
 arch/loongarch/kernel/traps.c           |  24 ++--
 arch/loongarch/kernel/unwind_guess.c    |  67 +++++++++
 arch/loongarch/kernel/unwind_prologue.c | 173 ++++++++++++++++++++++++
 15 files changed, 602 insertions(+), 17 deletions(-)
 create mode 100644 arch/loongarch/include/asm/unwind.h
 create mode 100644 arch/loongarch/kernel/stacktrace.c
 create mode 100644 arch/loongarch/kernel/unwind_guess.c
 create mode 100644 arch/loongarch/kernel/unwind_prologue.c

-- 
2.20.1
Re: [PATCH v4 0/4] Add unwinder support
Posted by Huacai Chen 5 days, 12 hours ago
Queued for 5.20,thanks.

Huacai

On Sat, Aug 6, 2022 at 4:10 PM Qing Zhang <zhangqing@loongson.cn> wrote:
>
> This series in order to add stacktrace support, Some upcoming features require
> these changes, like trace, divide unwinder into guess unwinder and prologue
> unwinder is to add new unwinders in the future.
> eg:unwinder_frame, unwinder_orc .etc.
>
> Three stages when we do unwind,
>   1) unwind_start(), the prapare of unwinding, fill unwind_state.
>   2) unwind_done(), judge whether the unwind process is finished or not.
>   3) unwind_next_frame(), unwind the next frame.
>
> you can test them by:
>   1) echo t > /proc/sysrq-trigger
>   2) cat /proc/*/stack
>   3) ftrace: function graph
>   4) uprobe: echo 1 > ./options/userstacktrace
>
> Changes from v1 to v2:
>
> - Add the judgment of the offset value of ra in the prologue.
>   (Suggested by Youling).
> - Create an inline function to check the sign bit, which is convenient
>   for extending other types of immediates.  (Suggested by Jinyang).
> - Fix sparse warning :
>     arch/loongarch/include/asm/uaccess.h:232:32: sparse: sparse: incorrect
>     type in argument 2 (different address spaces) @@     expected void const
>     *from @@     got void const [noderef] __user *from @@
> - Add USER_STACKTRACE support as a series.
>
> Changes from v2 to v3:
>
> - Move unwind_start definition and use location, remove #ifdef in unwind_state
>   and use type instead of enable. (Suggested by Huacai).
> - Separated fixes for uaccess.h. (Suggested by Huacai).
>
> Changes from v3 to v4:
>
> - Add get wchan implement. (Suggested by Huacai).
>
> Qing Zhang (4):
>   LoongArch: Add guess unwinder support
>   LoongArch: Add prologue unwinder support
>   LoongArch: Add stacktrace and get_wchan support
>   LoongArch: Add USER_STACKTRACE support
>
>  arch/loongarch/Kconfig                  |   6 +
>  arch/loongarch/Kconfig.debug            |  28 ++++
>  arch/loongarch/include/asm/inst.h       |  52 +++++++
>  arch/loongarch/include/asm/processor.h  |   9 ++
>  arch/loongarch/include/asm/stacktrace.h |  22 +++
>  arch/loongarch/include/asm/switch_to.h  |  14 +-
>  arch/loongarch/include/asm/unwind.h     |  47 +++++++
>  arch/loongarch/kernel/Makefile          |   4 +
>  arch/loongarch/kernel/asm-offsets.c     |   2 +
>  arch/loongarch/kernel/process.c         |  91 ++++++++++++-
>  arch/loongarch/kernel/stacktrace.c      |  78 +++++++++++
>  arch/loongarch/kernel/switch.S          |   2 +
>  arch/loongarch/kernel/traps.c           |  24 ++--
>  arch/loongarch/kernel/unwind_guess.c    |  67 +++++++++
>  arch/loongarch/kernel/unwind_prologue.c | 173 ++++++++++++++++++++++++
>  15 files changed, 602 insertions(+), 17 deletions(-)
>  create mode 100644 arch/loongarch/include/asm/unwind.h
>  create mode 100644 arch/loongarch/kernel/stacktrace.c
>  create mode 100644 arch/loongarch/kernel/unwind_guess.c
>  create mode 100644 arch/loongarch/kernel/unwind_prologue.c
>
> --
> 2.20.1
>