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Subject[PATCH RESEND] x86-64: use RIP-relative calls for paravirt indirect ones
This saves one insn byte per instance, summing up to a savings of over
4k in my (stripped down) configuration. No variant of to be patched in
replacement code relies on the one byte larger size.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
---
Resend to include x86 maintainers, who aren't listed explicitly for the
file changed.
---
arch/x86/include/asm/paravirt_types.h | 6 ++++++
1 file changed, 6 insertions(+)

--- 4.18/arch/x86/include/asm/paravirt_types.h
+++ 4.18-x86_64-pvops-call-RIPrel/arch/x86/include/asm/paravirt_types.h
@@ -393,9 +393,15 @@ int paravirt_disable_iospace(void);
* offset into the paravirt_patch_template structure, and can therefore be
* freely converted back into a structure offset.
*/
+#ifdef CONFIG_X86_32
#define PARAVIRT_CALL \
ANNOTATE_RETPOLINE_SAFE \
"call *%c[paravirt_opptr];"
+#else
+#define PARAVIRT_CALL \
+ ANNOTATE_RETPOLINE_SAFE \
+ "call *%c[paravirt_opptr](%%rip);"
+#endif

/*
* These macros are intended to wrap calls through one of the paravirt

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