* [PATCH] x86-64: use RIP-relative calls for paravirt indirect ones
@ 2018-06-25 10:29 Jan Beulich
2018-08-15 8:09 ` [PATCH RESEND] " Jan Beulich
2018-08-15 8:09 ` Jan Beulich
0 siblings, 2 replies; 5+ messages in thread
From: Jan Beulich @ 2018-06-25 10:29 UTC (permalink / raw)
To: Juergen Gross, Alok Kataria; +Cc: virtualization
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>
---
arch/x86/include/asm/paravirt_types.h | 6 ++++++
1 file changed, 6 insertions(+)
--- 4.18-rc2/arch/x86/include/asm/paravirt_types.h
+++ 4.18-rc2-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
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH RESEND] x86-64: use RIP-relative calls for paravirt indirect ones
2018-06-25 10:29 [PATCH] x86-64: use RIP-relative calls for paravirt indirect ones Jan Beulich
@ 2018-08-15 8:09 ` Jan Beulich
2018-08-20 14:54 ` Thomas Gleixner
2018-08-15 8:09 ` Jan Beulich
1 sibling, 1 reply; 5+ messages in thread
From: Jan Beulich @ 2018-08-15 8:09 UTC (permalink / raw)
To: the arch/x86 maintainers, Juergen Gross, Alok Kataria
Cc: Linux Virtualization, linux-kernel, hpa
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
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH RESEND] x86-64: use RIP-relative calls for paravirt indirect ones
2018-06-25 10:29 [PATCH] x86-64: use RIP-relative calls for paravirt indirect ones Jan Beulich
2018-08-15 8:09 ` [PATCH RESEND] " Jan Beulich
@ 2018-08-15 8:09 ` Jan Beulich
1 sibling, 0 replies; 5+ messages in thread
From: Jan Beulich @ 2018-08-15 8:09 UTC (permalink / raw)
To: the arch/x86 maintainers, Juergen Gross, Alok Kataria
Cc: hpa, linux-kernel, Linux Virtualization
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
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] x86-64: use RIP-relative calls for paravirt indirect ones
2018-08-15 8:09 ` [PATCH RESEND] " Jan Beulich
@ 2018-08-20 14:54 ` Thomas Gleixner
0 siblings, 0 replies; 5+ messages in thread
From: Thomas Gleixner @ 2018-08-20 14:54 UTC (permalink / raw)
To: Jan Beulich
Cc: the arch/x86 maintainers, Juergen Gross, Alok Kataria,
Linux Virtualization, linux-kernel, hpa
On Wed, 15 Aug 2018, Jan Beulich wrote:
> 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>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH RESEND] x86-64: use RIP-relative calls for paravirt indirect ones
@ 2018-08-20 14:54 ` Thomas Gleixner
0 siblings, 0 replies; 5+ messages in thread
From: Thomas Gleixner @ 2018-08-20 14:54 UTC (permalink / raw)
To: Jan Beulich
Cc: Juergen Gross, the arch/x86 maintainers, linux-kernel,
Linux Virtualization, hpa, Alok Kataria
On Wed, 15 Aug 2018, Jan Beulich wrote:
> 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>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2018-08-20 14:55 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2018-06-25 10:29 [PATCH] x86-64: use RIP-relative calls for paravirt indirect ones Jan Beulich
2018-08-15 8:09 ` [PATCH RESEND] " Jan Beulich
2018-08-20 14:54 ` Thomas Gleixner
2018-08-20 14:54 ` Thomas Gleixner
2018-08-15 8:09 ` Jan Beulich
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