Similar to struct alt_instr, make the struct paravirt_patch_site packed
and get rid of all the .align directives. This could save 2 bytes for
one entry on X86_64.
Suggested-by: Nadav Amit <[email protected]>
Signed-off-by: Hou Wenlong <[email protected]>
---
arch/x86/include/asm/paravirt.h | 2 --
arch/x86/include/asm/paravirt_types.h | 4 +---
2 files changed, 1 insertion(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 2350ceb43db0..3e5ccacb3893 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -747,11 +747,9 @@ extern void default_banner(void);
ops; \
772:; \
.pushsection .parainstructions,"a"; \
- .align 4; \
.long 771b-.; \
.byte ptype; \
.byte 772b-771b; \
- .align 4; \
.popsection
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index 982a234f5a06..da0547bcd068 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -8,7 +8,7 @@ struct paravirt_patch_site {
s32 instr_offset; /* original instructions */
u8 type; /* type of this instruction */
u8 len; /* length of original instruction */
-};
+} __packed;
/* Lazy mode for batching updates / context switch */
enum paravirt_lazy_mode {
@@ -270,11 +270,9 @@ extern struct paravirt_patch_template pv_ops;
#define _paravirt_alt(insn_string, type) \
"771:\n\t" insn_string "\n" "772:\n" \
".pushsection .parainstructions,\"a\"\n" \
- " .align 4\n" \
" .long 771b-.\n" \
" .byte " type "\n" \
" .byte 772b-771b\n" \
- " .align 4\n" \
".popsection\n"
/* Generate patchable code, with the default asm parameters. */
--
2.31.1
On 09.06.23 11:45, Hou Wenlong wrote:
> Similar to struct alt_instr, make the struct paravirt_patch_site packed
> and get rid of all the .align directives. This could save 2 bytes for
> one entry on X86_64.
>
> Suggested-by: Nadav Amit <[email protected]>
> Signed-off-by: Hou Wenlong <[email protected]>
Reviewed-by: Juergen Gross <[email protected]>
Juergen
> On Jun 9, 2023, at 2:45 AM, Hou Wenlong <[email protected]> wrote:
>
> Similar to struct alt_instr, make the struct paravirt_patch_site packed
> and get rid of all the .align directives. This could save 2 bytes for
> one entry on X86_64.
Thanks for taking care of it.