[PATCH V17 3/7] powerpc/jump_label: adjust inline asm to be consistent
From: Mukesh Kumar Chaurasiya (IBM) <hidden>
Date: 2026-07-08 08:25:52
Also in:
lkml, llvm, rust-for-linux
Subsystem:
linux for powerpc (32-bit and 64-bit), static branch/call, the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Peter Zijlstra, Josh Poimboeuf, Jason Baron, Alice Ryhl, Linus Torvalds
Added support for a new macro ARCH_STATIC_BRANCH_ASM in powerpc
to avoid duplication of inline asm between C and Rust. This is
inline with 'commit aecaf181651c ("jump_label: adjust inline asm to be consistent")'
Co-developed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://github.com/Rust-for-Linux/linux/issues/105
Link: https://github.com/linuxppc/issues/issues/451
Signed-off-by: Mukesh Kumar Chaurasiya (IBM) <redacted>
---
arch/powerpc/include/asm/jump_label.h | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/asm/jump_label.h
index d4eaba459a0e..3016e9c8d6bc 100644
--- a/arch/powerpc/include/asm/jump_label.h
+++ b/arch/powerpc/include/asm/jump_label.h@@ -15,14 +15,20 @@ #define JUMP_ENTRY_TYPE stringify_in_c(FTR_ENTRY_LONG) #define JUMP_LABEL_NOP_SIZE 4 +#define JUMP_TABLE_ENTRY(key, label) \ + ".pushsection __jump_table, \"aw\" \n\t" \ + ".long 1b - ., " label " - . \n\t" \ + JUMP_ENTRY_TYPE key " - . \n\t" \ + ".popsection \n\t" + +#define ARCH_STATIC_BRANCH_ASM(key, label) \ + "1: nop \n\t" \ + JUMP_TABLE_ENTRY(key, label) + static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { - asm goto("1:\n\t" - "nop # arch_static_branch\n\t" - ".pushsection __jump_table, \"aw\"\n\t" - ".long 1b - ., %l[l_yes] - .\n\t" - JUMP_ENTRY_TYPE "%c0 - .\n\t" - ".popsection \n\t" + asm goto( + ARCH_STATIC_BRANCH_ASM("%c0", "%l[l_yes]") : : "i" (&((char *)key)[branch]) : : l_yes); return false;
@@ -34,10 +40,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool { asm goto("1:\n\t" "b %l[l_yes] # arch_static_branch_jump\n\t" - ".pushsection __jump_table, \"aw\"\n\t" - ".long 1b - ., %l[l_yes] - .\n\t" - JUMP_ENTRY_TYPE "%c0 - .\n\t" - ".popsection \n\t" + JUMP_TABLE_ENTRY("%c0", "%l[l_yes]") : : "i" (&((char *)key)[branch]) : : l_yes); return false;
--
2.55.0