| Message ID | 20230109135828.879136-4-mark.rutland@arm.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | arm64/ftrace: Add support for DYNAMIC_FTRACE_WITH_CALL_OPS | expand |
diff --git a/arch/arm64/include/asm/linkage.h b/arch/arm64/include/asm/linkage.h index 1436fa1cde24d..df18a3446ce82 100644 --- a/arch/arm64/include/asm/linkage.h +++ b/arch/arm64/include/asm/linkage.h @@ -5,8 +5,14 @@ #include <asm/assembler.h> #endif -#define __ALIGN .align 2 -#define __ALIGN_STR ".align 2" +#if CONFIG_FUNCTION_ALIGNMENT > 0 +#define ARM64_FUNCTION_ALIGNMENT CONFIG_FUNCTION_ALIGNMENT +#else +#define ARM64_FUNCTION_ALIGNMENT 4 +#endif + +#define __ALIGN .balign ARM64_FUNCTION_ALIGNMENT +#define __ALIGN_STR ".balign " #ARM64_FUNCTION_ALIGNMENT /* * When using in-kernel BTI we need to ensure that PCS-conformant
On arm64 we don't align assembly funciton in the same way as C functions. This somewhat limits the utility of CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B for testing. Follow the example of x86, and align assembly functions in the same way as C functions. I've tested this by selecting CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B=y, building and booting a kernel, and looking for misaligned text symbols: Before: # grep ' [Tt] ' /proc/kallsyms | grep -iv '[048c]0 [Tt] ' | wc -l 322 After: # grep ' [Tt] ' /proc/kallsyms | grep -iv '[048c]0 [Tt] ' | wc -l 115 The remaining unaligned text symbols are a combination of non-function labels in assembly and early position-independent code which is built with '-Os'. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Deacon <will@kernel.org> --- arch/arm64/include/asm/linkage.h | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)