[PATCH V14 3/7] powerpc/jump_label: adjust inline asm to be consistent

Mukesh Kumar Chaurasiya (IBM)
2026-04-26T08:58:23Z

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) <mkchauras@gmail.com>
---
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;
--
2.53.0