| Message ID | 20230306081042.299871-1-sv@linux.ibm.com (mailing list archive) |
|---|---|
| State | RFC |
| Headers | show |
| Series | [RFC] powerpc/Kconfig: Select FUNCTION_ALIGNMENT_4B | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/github-powerpc_ppctests | success | Successfully ran 8 jobs. |
| snowpatch_ozlabs/github-powerpc_selftests | success | Successfully ran 8 jobs. |
| snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
| snowpatch_ozlabs/github-powerpc_kernel_qemu | success | Successfully ran 24 jobs. |
| snowpatch_ozlabs/github-powerpc_clang | success | Successfully ran 6 jobs. |
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index a6c4407d3ec8..ac3f80c0db36 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -174,6 +174,7 @@ config PPC select DYNAMIC_FTRACE if FUNCTION_TRACER select EDAC_ATOMIC_SCRUB select EDAC_SUPPORT + select FUNCTION_ALIGNMENT_4B select GENERIC_ATOMIC64 if PPC32 select GENERIC_CLOCKEVENTS_BROADCAST if SMP select GENERIC_CMOS_UPDATE diff --git a/arch/powerpc/include/asm/linkage.h b/arch/powerpc/include/asm/linkage.h index b88d1d2cf304..b71b9582e754 100644 --- a/arch/powerpc/include/asm/linkage.h +++ b/arch/powerpc/include/asm/linkage.h @@ -4,9 +4,6 @@ #include <asm/types.h> -#define __ALIGN .align 2 -#define __ALIGN_STR ".align 2" - #ifdef CONFIG_PPC64_ELF_ABI_V1 #define cond_syscall(x) \ asm ("\t.weak " #x "\n\t.set " #x ", sys_ni_syscall\n" \
Commit d49a0626216b95 ("arch: Introduce CONFIG_FUNCTION_ALIGNMENT") introduced a generic function-alignment infrastructure. Move to using FUNCTION_ALIGNMENT_4B on powerpc, to use the same alignment as that of the existing _GLOBAL macro. Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com> Note: Given that alignment beyond the minimum requirement may be desirable, should we instead select FUNCTION_ALIGNMENT_16B for ppc64 and select FUNCTION_ALIGNMENT_4B/8B for ppc32? From vmlinux (pseries_le_defconfig) symbol offsets, it looks like most of the ppc64 symbols are being aligned to a 16B boundary, but there are a few which are not. Currently, size of vmlinux (built with pseries_le_defconfig) is 47090kB. With FUNCTION_ALIGNMENT_4B selected, size of vmlinux is 47152kB. With FUNCTION_ALIGNMENT_16B selected, size of vmlinux is 47152kB. Currently, size of vmlinux (built with powernv_defconfig) is 42852kB. With FUNCTION_ALIGNMENT_4B selected, size of vmlinux is 42911kB. With FUNCTION_ALIGNMENT_16B selected, size of vmlinux is 42977kB. I am wondering if we should use the same alignment as that of _GLOBAL macro or have alignment set to a 8B/16B boundary. Please let me know your thoughts on the same. Thanks! --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/linkage.h | 3 --- 2 files changed, 1 insertion(+), 3 deletions(-)