[PATCH v4 0/4] openrisc: Support basic trace mechanism

[ChenMiao <chenmiao.ku@gmail.com>]

From: chenmiao <chenmiao.ku@gmail.com>

Hello everyone,

This implements a basic text patching mechanism and a complete jump_label
implementation for OpenRISC. It should be noted that the jump_label have
passed testing.

1. Implement the patch_map interface and the patch_insn_write single insn
write API by providing FIX_TEXT_POKE0. And create a new insn-def.h to record
openrisc's instruction macro definition which only have OPENRISC_INSN_SIZE
now.

2. Support for the R_OR1K_32_PCREL relocation type is added for module insertion,
enabling subsequent jump_label selftest module insertion.

3. Regenerate defconfigs for or1ksim_defconfig and virt_defconfig.

4. Based on the previously implemented patch_insn_write, achieve a complete
jump_label implementation, directly supporting arch_jump_label_transform_queue.
And add a new macro OPENRISC_INSN_NOP in insn-def.h.

Link: https://lore.kernel.org/openrisc/20250805084926.4125564-1-chenmiao.ku@gmail.com/T/#u

Thanks,

Chen Miao

---
Changes in V4:
  - Added testing for jump_label
  - Split part of the jump_label patch content to form the third patch
  - Implemented R_OR1K_32_PCREL module support for jump_label testing

Changes in V3:
  - Removed the is_exit_text used, added some necessary comments.
  - Modify some macro like __ASSEMBLY__ to __ASSEMBLER__ and ensure the
    defconfig by make savedefconfig.

Changes in V2:
  - Add a new insn-def.h to record the insn macro.
  - Modify the patch_insn_write API from const void* to u32 insn.
  - Using the modified patch_insn_write API in 
    arch_jump_label_transform_queue.

chenmiao (4):
  openrisc: Add text patching API support
  openrisc: Add R_OR1K_32_PCREL relocation type module support
  openrisc: Regenerate defconfigs.
  openrisc: Add jump label support

 .../core/jump-labels/arch-support.txt         |  2 +-
 arch/openrisc/Kconfig                         |  2 +
 arch/openrisc/configs/or1ksim_defconfig       | 19 ++---
 arch/openrisc/configs/virt_defconfig          |  2 +-
 arch/openrisc/include/asm/Kbuild              |  1 -
 arch/openrisc/include/asm/fixmap.h            |  1 +
 arch/openrisc/include/asm/insn-def.h          | 15 ++++
 arch/openrisc/include/asm/jump_label.h        | 72 +++++++++++++++++
 arch/openrisc/include/asm/text-patching.h     | 13 +++
 arch/openrisc/kernel/Makefile                 |  2 +
 arch/openrisc/kernel/jump_label.c             | 52 ++++++++++++
 arch/openrisc/kernel/module.c                 |  4 +
 arch/openrisc/kernel/patching.c               | 79 +++++++++++++++++++
 arch/openrisc/kernel/setup.c                  |  2 +
 arch/openrisc/mm/init.c                       |  6 +-
 15 files changed, 256 insertions(+), 16 deletions(-)
 create mode 100644 arch/openrisc/include/asm/insn-def.h
 create mode 100644 arch/openrisc/include/asm/jump_label.h
 create mode 100644 arch/openrisc/include/asm/text-patching.h
 create mode 100644 arch/openrisc/kernel/jump_label.c
 create mode 100644 arch/openrisc/kernel/patching.c

-- 
2.45.2