Commit 2c5ce2db authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'x86_alternatives_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 alternatives/paravirt updates from Borislav Petkov:
 "First big cleanup to the paravirt infra to use alternatives and thus
  eliminate custom code patching.

  For that, the alternatives infrastructure is extended to accomodate
  paravirt's needs and, as a result, a lot of paravirt patching code
  goes away, leading to a sizeable cleanup and simplification.

  Work by Juergen Gross"

* tag 'x86_alternatives_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/paravirt: Have only one paravirt patch function
  x86/paravirt: Switch functions with custom code to ALTERNATIVE
  x86/paravirt: Add new PVOP_ALT* macros to support pvops in ALTERNATIVEs
  x86/paravirt: Switch iret pvops to ALTERNATIVE
  x86/paravirt: Simplify paravirt macros
  x86/paravirt: Remove no longer needed 32-bit pvops cruft
  x86/paravirt: Add new features for paravirt patching
  x86/alternative: Use ALTERNATIVE_TERNARY() in _static_cpu_has()
  x86/alternative: Support ALTERNATIVE_TERNARY
  x86/alternative: Support not-feature
  x86/paravirt: Switch time pvops functions to use static_call()
  static_call: Add function to query current function
  static_call: Move struct static_call_key definition to static_call_types.h
  x86/alternative: Merge include files
  x86/alternative: Drop unused feature parameter from ALTINSTR_REPLACEMENT()
parents 2c532791 054ac8ad

arch/arm/include/asm/paravirt.h

+5 −9
Original line number Diff line number Diff line
@@ -3,23 +3,19 @@ 
#define _ASM_ARM_PARAVIRT_H



#ifdef CONFIG_PARAVIRT

#include <linux/static_call_types.h>



struct static_key;

extern struct static_key paravirt_steal_enabled;

extern struct static_key paravirt_steal_rq_enabled;



struct pv_time_ops {

	unsigned long long (*steal_clock)(int cpu);

};



struct paravirt_patch_template {

	struct pv_time_ops time;

};

u64 dummy_steal_clock(int cpu);



extern struct paravirt_patch_template pv_ops;

DECLARE_STATIC_CALL(pv_steal_clock, dummy_steal_clock);



static inline u64 paravirt_steal_clock(int cpu)

{

	return pv_ops.time.steal_clock(cpu);

	return static_call(pv_steal_clock)(cpu);

}

#endif

arch/arm/kernel/paravirt.c

+7 −2
Original line number Diff line number Diff line
@@ -9,10 +9,15 @@ 
#include <linux/export.h>

#include <linux/jump_label.h>

#include <linux/types.h>

#include <linux/static_call.h>

#include <asm/paravirt.h>



struct static_key paravirt_steal_enabled;

struct static_key paravirt_steal_rq_enabled;



struct paravirt_patch_template pv_ops;

EXPORT_SYMBOL_GPL(pv_ops);
 
static u64 native_steal_clock(int cpu)

{

	return 0;

}



DEFINE_STATIC_CALL(pv_steal_clock, native_steal_clock);

arch/arm64/include/asm/paravirt.h

+5 −9
Original line number Diff line number Diff line
@@ -3,23 +3,19 @@ 
#define _ASM_ARM64_PARAVIRT_H



#ifdef CONFIG_PARAVIRT

#include <linux/static_call_types.h>



struct static_key;

extern struct static_key paravirt_steal_enabled;

extern struct static_key paravirt_steal_rq_enabled;



struct pv_time_ops {

	unsigned long long (*steal_clock)(int cpu);

};



struct paravirt_patch_template {

	struct pv_time_ops time;

};

u64 dummy_steal_clock(int cpu);



extern struct paravirt_patch_template pv_ops;

DECLARE_STATIC_CALL(pv_steal_clock, dummy_steal_clock);



static inline u64 paravirt_steal_clock(int cpu)

{

	return pv_ops.time.steal_clock(cpu);

	return static_call(pv_steal_clock)(cpu);

}



int __init pv_time_init(void);

arch/arm64/kernel/paravirt.c

+9 −4
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <linux/reboot.h>

#include <linux/slab.h>

#include <linux/types.h>

#include <linux/static_call.h>



#include <asm/paravirt.h>

#include <asm/pvclock-abi.h>
@@ -26,8 +27,12 @@ 
struct static_key paravirt_steal_enabled;

struct static_key paravirt_steal_rq_enabled;



struct paravirt_patch_template pv_ops;

EXPORT_SYMBOL_GPL(pv_ops);

static u64 native_steal_clock(int cpu)

{

	return 0;

}



DEFINE_STATIC_CALL(pv_steal_clock, native_steal_clock);



struct pv_time_stolen_time_region {

	struct pvclock_vcpu_stolen_time *kaddr;
@@ -45,7 +50,7 @@ static int __init parse_no_stealacc(char *arg) 
early_param("no-steal-acc", parse_no_stealacc);



/* return stolen time in ns by asking the hypervisor */

static u64 pv_steal_clock(int cpu)

static u64 para_steal_clock(int cpu)

{

	struct pv_time_stolen_time_region *reg;
@@ -150,7 +155,7 @@ int __init pv_time_init(void) 
	if (ret)

		return ret;



	pv_ops.time.steal_clock = pv_steal_clock;

	static_call_update(pv_steal_clock, para_steal_clock);



	static_key_slow_inc(&paravirt_steal_enabled);

	if (steal_acc)

arch/x86/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -777,6 +777,7 @@ if HYPERVISOR_GUEST 


config PARAVIRT

	bool "Enable paravirtualization code"

	depends on HAVE_STATIC_CALL

	help

	  This changes the kernel so it can modify itself when it is run

	  under a hypervisor, potentially improving performance significantly