Commit da5de7c2 authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge Committed by H. Peter Anvin
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x86/paravirt: use callee-saved convention for pte_val/make_pte/etc 



Impact: Optimization

In the native case, pte_val, make_pte, etc are all just identity
functions, so there's no need to clobber a lot of registers over them.

(This changes the 32-bit callee-save calling convention to return both
EAX and EDX so functions can return 64-bit values.)

Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
parent 791bad9d

arch/x86/include/asm/paravirt.h

+39 −39
Original line number Diff line number Diff line
@@ -19,7 +19,7 @@ 
#define CLBR_ANY  ((1 << 4) - 1)



#define CLBR_ARG_REGS	(CLBR_EAX | CLBR_EDX | CLBR_ECX)

#define CLBR_RET_REG	(CLBR_EAX)

#define CLBR_RET_REG	(CLBR_EAX | CLBR_EDX)

#define CLBR_SCRATCH	(0)

#else

#define CLBR_RAX  CLBR_EAX
@@ -308,11 +308,11 @@ struct pv_mmu_ops { 
	void (*ptep_modify_prot_commit)(struct mm_struct *mm, unsigned long addr,

					pte_t *ptep, pte_t pte);



	pteval_t (*pte_val)(pte_t);

	pte_t (*make_pte)(pteval_t pte);

	struct paravirt_callee_save pte_val;

	struct paravirt_callee_save make_pte;



	pgdval_t (*pgd_val)(pgd_t);

	pgd_t (*make_pgd)(pgdval_t pgd);

	struct paravirt_callee_save pgd_val;

	struct paravirt_callee_save make_pgd;



#if PAGETABLE_LEVELS >= 3

#ifdef CONFIG_X86_PAE
@@ -327,12 +327,12 @@ struct pv_mmu_ops { 


	void (*set_pud)(pud_t *pudp, pud_t pudval);



	pmdval_t (*pmd_val)(pmd_t);

	pmd_t (*make_pmd)(pmdval_t pmd);

	struct paravirt_callee_save pmd_val;

	struct paravirt_callee_save make_pmd;



#if PAGETABLE_LEVELS == 4

	pudval_t (*pud_val)(pud_t);

	pud_t (*make_pud)(pudval_t pud);

	struct paravirt_callee_save pud_val;

	struct paravirt_callee_save make_pud;



	void (*set_pgd)(pgd_t *pudp, pgd_t pgdval);

#endif	/* PAGETABLE_LEVELS == 4 */
@@ -1155,11 +1155,11 @@ static inline pte_t __pte(pteval_t val) 
	pteval_t ret;



	if (sizeof(pteval_t) > sizeof(long))

		ret = PVOP_CALL2(pteval_t,

		ret = PVOP_CALLEE2(pteval_t,

				   pv_mmu_ops.make_pte,

				   val, (u64)val >> 32);

	else

		ret = PVOP_CALL1(pteval_t,

		ret = PVOP_CALLEE1(pteval_t,

				   pv_mmu_ops.make_pte,

				   val);
@@ -1171,10 +1171,10 @@ static inline pteval_t pte_val(pte_t pte) 
	pteval_t ret;



	if (sizeof(pteval_t) > sizeof(long))

		ret = PVOP_CALL2(pteval_t, pv_mmu_ops.pte_val,

		ret = PVOP_CALLEE2(pteval_t, pv_mmu_ops.pte_val,

				   pte.pte, (u64)pte.pte >> 32);

	else

		ret = PVOP_CALL1(pteval_t, pv_mmu_ops.pte_val,

		ret = PVOP_CALLEE1(pteval_t, pv_mmu_ops.pte_val,

				   pte.pte);



	return ret;
@@ -1185,10 +1185,10 @@ static inline pgd_t __pgd(pgdval_t val) 
	pgdval_t ret;



	if (sizeof(pgdval_t) > sizeof(long))

		ret = PVOP_CALL2(pgdval_t, pv_mmu_ops.make_pgd,

		ret = PVOP_CALLEE2(pgdval_t, pv_mmu_ops.make_pgd,

				   val, (u64)val >> 32);

	else

		ret = PVOP_CALL1(pgdval_t, pv_mmu_ops.make_pgd,

		ret = PVOP_CALLEE1(pgdval_t, pv_mmu_ops.make_pgd,

				   val);



	return (pgd_t) { ret };
@@ -1199,10 +1199,10 @@ static inline pgdval_t pgd_val(pgd_t pgd) 
	pgdval_t ret;



	if (sizeof(pgdval_t) > sizeof(long))

		ret =  PVOP_CALL2(pgdval_t, pv_mmu_ops.pgd_val,

		ret =  PVOP_CALLEE2(pgdval_t, pv_mmu_ops.pgd_val,

				    pgd.pgd, (u64)pgd.pgd >> 32);

	else

		ret =  PVOP_CALL1(pgdval_t, pv_mmu_ops.pgd_val,

		ret =  PVOP_CALLEE1(pgdval_t, pv_mmu_ops.pgd_val,

				    pgd.pgd);



	return ret;
@@ -1267,10 +1267,10 @@ static inline pmd_t __pmd(pmdval_t val) 
	pmdval_t ret;



	if (sizeof(pmdval_t) > sizeof(long))

		ret = PVOP_CALL2(pmdval_t, pv_mmu_ops.make_pmd,

		ret = PVOP_CALLEE2(pmdval_t, pv_mmu_ops.make_pmd,

				   val, (u64)val >> 32);

	else

		ret = PVOP_CALL1(pmdval_t, pv_mmu_ops.make_pmd,

		ret = PVOP_CALLEE1(pmdval_t, pv_mmu_ops.make_pmd,

				   val);



	return (pmd_t) { ret };
@@ -1281,10 +1281,10 @@ static inline pmdval_t pmd_val(pmd_t pmd) 
	pmdval_t ret;



	if (sizeof(pmdval_t) > sizeof(long))

		ret =  PVOP_CALL2(pmdval_t, pv_mmu_ops.pmd_val,

		ret =  PVOP_CALLEE2(pmdval_t, pv_mmu_ops.pmd_val,

				    pmd.pmd, (u64)pmd.pmd >> 32);

	else

		ret =  PVOP_CALL1(pmdval_t, pv_mmu_ops.pmd_val,

		ret =  PVOP_CALLEE1(pmdval_t, pv_mmu_ops.pmd_val,

				    pmd.pmd);



	return ret;
@@ -1307,10 +1307,10 @@ static inline pud_t __pud(pudval_t val) 
	pudval_t ret;



	if (sizeof(pudval_t) > sizeof(long))

		ret = PVOP_CALL2(pudval_t, pv_mmu_ops.make_pud,

		ret = PVOP_CALLEE2(pudval_t, pv_mmu_ops.make_pud,

				   val, (u64)val >> 32);

	else

		ret = PVOP_CALL1(pudval_t, pv_mmu_ops.make_pud,

		ret = PVOP_CALLEE1(pudval_t, pv_mmu_ops.make_pud,

				   val);



	return (pud_t) { ret };

arch/x86/kernel/paravirt.c

+12 −41
Original line number Diff line number Diff line
@@ -391,43 +391,12 @@ struct pv_apic_ops pv_apic_ops = { 
#endif

};



typedef pte_t make_pte_t(pteval_t);

typedef pmd_t make_pmd_t(pmdval_t);

typedef pud_t make_pud_t(pudval_t);

typedef pgd_t make_pgd_t(pgdval_t);



typedef pteval_t pte_val_t(pte_t);

typedef pmdval_t pmd_val_t(pmd_t);

typedef pudval_t pud_val_t(pud_t);

typedef pgdval_t pgd_val_t(pgd_t);





#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)

/* 32-bit pagetable entries */

#define paravirt_native_make_pte	(make_pte_t *)_paravirt_ident_32

#define paravirt_native_pte_val		(pte_val_t *)_paravirt_ident_32



#define paravirt_native_make_pmd	(make_pmd_t *)_paravirt_ident_32

#define paravirt_native_pmd_val		(pmd_val_t *)_paravirt_ident_32



#define paravirt_native_make_pud	(make_pud_t *)_paravirt_ident_32

#define paravirt_native_pud_val		(pud_val_t *)_paravirt_ident_32



#define paravirt_native_make_pgd	(make_pgd_t *)_paravirt_ident_32

#define paravirt_native_pgd_val		(pgd_val_t *)_paravirt_ident_32

#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_32)

#else

/* 64-bit pagetable entries */

#define paravirt_native_make_pte	(make_pte_t *)_paravirt_ident_64

#define paravirt_native_pte_val		(pte_val_t *)_paravirt_ident_64



#define paravirt_native_make_pmd	(make_pmd_t *)_paravirt_ident_64

#define paravirt_native_pmd_val		(pmd_val_t *)_paravirt_ident_64



#define paravirt_native_make_pud	(make_pud_t *)_paravirt_ident_64

#define paravirt_native_pud_val		(pud_val_t *)_paravirt_ident_64



#define paravirt_native_make_pgd	(make_pgd_t *)_paravirt_ident_64

#define paravirt_native_pgd_val		(pgd_val_t *)_paravirt_ident_64

#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_64)

#endif



struct pv_mmu_ops pv_mmu_ops = {
@@ -481,21 +450,23 @@ struct pv_mmu_ops pv_mmu_ops = { 
	.pmd_clear = native_pmd_clear,

#endif

	.set_pud = native_set_pud,

	.pmd_val = paravirt_native_pmd_val,

	.make_pmd = paravirt_native_make_pmd,



	.pmd_val = PTE_IDENT,

	.make_pmd = PTE_IDENT,



#if PAGETABLE_LEVELS == 4

	.pud_val = paravirt_native_pud_val,

	.make_pud = paravirt_native_make_pud,

	.pud_val = PTE_IDENT,

	.make_pud = PTE_IDENT,



	.set_pgd = native_set_pgd,

#endif

#endif /* PAGETABLE_LEVELS >= 3 */



	.pte_val = paravirt_native_pte_val,

	.pgd_val = paravirt_native_pgd_val,

	.pte_val = PTE_IDENT,

	.pgd_val = PTE_IDENT,



	.make_pte = paravirt_native_make_pte,

	.make_pgd = paravirt_native_make_pgd,

	.make_pte = PTE_IDENT,

	.make_pgd = PTE_IDENT,



	.dup_mmap = paravirt_nop,

	.exit_mmap = paravirt_nop,

arch/x86/xen/mmu.c

+16 −8
Original line number Diff line number Diff line
@@ -492,28 +492,33 @@ pteval_t xen_pte_val(pte_t pte) 
{

	return pte_mfn_to_pfn(pte.pte);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);



pgdval_t xen_pgd_val(pgd_t pgd)

{

	return pte_mfn_to_pfn(pgd.pgd);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val);



pte_t xen_make_pte(pteval_t pte)

{

	pte = pte_pfn_to_mfn(pte);

	return native_make_pte(pte);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);



pgd_t xen_make_pgd(pgdval_t pgd)

{

	pgd = pte_pfn_to_mfn(pgd);

	return native_make_pgd(pgd);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_make_pgd);



pmdval_t xen_pmd_val(pmd_t pmd)

{

	return pte_mfn_to_pfn(pmd.pmd);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_pmd_val);



void xen_set_pud_hyper(pud_t *ptr, pud_t val)

{
@@ -590,12 +595,14 @@ pmd_t xen_make_pmd(pmdval_t pmd) 
	pmd = pte_pfn_to_mfn(pmd);

	return native_make_pmd(pmd);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd);



#if PAGETABLE_LEVELS == 4

pudval_t xen_pud_val(pud_t pud)

{

	return pte_mfn_to_pfn(pud.pud);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_pud_val);



pud_t xen_make_pud(pudval_t pud)

{
@@ -603,6 +610,7 @@ pud_t xen_make_pud(pudval_t pud) 


	return native_make_pud(pud);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_make_pud);



pgd_t *xen_get_user_pgd(pgd_t *pgd)

{
@@ -1813,11 +1821,11 @@ const struct pv_mmu_ops xen_mmu_ops __initdata = { 
	.ptep_modify_prot_start = __ptep_modify_prot_start,

	.ptep_modify_prot_commit = __ptep_modify_prot_commit,



	.pte_val = xen_pte_val,

	.pgd_val = xen_pgd_val,

	.pte_val = PV_CALLEE_SAVE(xen_pte_val),

	.pgd_val = PV_CALLEE_SAVE(xen_pgd_val),



	.make_pte = xen_make_pte,

	.make_pgd = xen_make_pgd,

	.make_pte = PV_CALLEE_SAVE(xen_make_pte),

	.make_pgd = PV_CALLEE_SAVE(xen_make_pgd),



#ifdef CONFIG_X86_PAE

	.set_pte_atomic = xen_set_pte_atomic,
@@ -1827,12 +1835,12 @@ const struct pv_mmu_ops xen_mmu_ops __initdata = { 
#endif	/* CONFIG_X86_PAE */

	.set_pud = xen_set_pud_hyper,



	.make_pmd = xen_make_pmd,

	.pmd_val = xen_pmd_val,

	.make_pmd = PV_CALLEE_SAVE(xen_make_pmd),

	.pmd_val = PV_CALLEE_SAVE(xen_pmd_val),



#if PAGETABLE_LEVELS == 4

	.pud_val = xen_pud_val,

	.make_pud = xen_make_pud,

	.pud_val = PV_CALLEE_SAVE(xen_pud_val),

	.make_pud = PV_CALLEE_SAVE(xen_make_pud),

	.set_pgd = xen_set_pgd_hyper,



	.alloc_pud = xen_alloc_pte_init,

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