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Subject[PATCH 2/2] x86/paravirt: Make the struct paravirt_patch_site packed
Date
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 <namit@vmware.com>
Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com>
---
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
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