Commit a2e7f0e3 authored by Andi Kleen's avatar Andi Kleen Committed by H. Peter Anvin
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x86, asmlinkage, paravirt: Make paravirt thunks global 



The paravirt thunks use a hack of using a static reference to a static
function to reference that function from the top level statement.

This assumes that gcc always generates static function names in a specific
format, which is not necessarily true.

Simply make these functions global and asmlinkage or __visible. This way the
static __used variables are not needed and everything works.

Functions with arguments are __visible to keep the register calling
convention on 32bit.

Changed in paravirt and in all users (Xen and vsmp)

v2: Use __visible for functions with arguments

Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ido Yariv <ido@wizery.com>
Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1382458079-24450-5-git-send-email-andi@firstfloor.org


Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent 824a2870

arch/x86/include/asm/paravirt.h

+1 −1
Original line number Diff line number Diff line
@@ -781,9 +781,9 @@ static __always_inline void __ticket_unlock_kick(struct arch_spinlock *lock, 
 */

#define PV_CALLEE_SAVE_REGS_THUNK(func)					\

	extern typeof(func) __raw_callee_save_##func;			\

	static void *__##func##__ __used = func;			\

									\

	asm(".pushsection .text;"					\

	    ".globl __raw_callee_save_" #func " ; "			\

	    "__raw_callee_save_" #func ": "				\

	    PV_SAVE_ALL_CALLER_REGS					\

	    "call " #func ";"						\

arch/x86/kernel/vsmp_64.c

+4 −4
Original line number Diff line number Diff line
@@ -33,7 +33,7 @@ 
 * and vice versa.

 */



static unsigned long vsmp_save_fl(void)

asmlinkage unsigned long vsmp_save_fl(void)

{

	unsigned long flags = native_save_fl();
@@ -43,7 +43,7 @@ static unsigned long vsmp_save_fl(void) 
}

PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl);



static void vsmp_restore_fl(unsigned long flags)

__visible void vsmp_restore_fl(unsigned long flags)

{

	if (flags & X86_EFLAGS_IF)

		flags &= ~X86_EFLAGS_AC;
@@ -53,7 +53,7 @@ static void vsmp_restore_fl(unsigned long flags) 
}

PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl);



static void vsmp_irq_disable(void)

asmlinkage void vsmp_irq_disable(void)

{

	unsigned long flags = native_save_fl();
@@ -61,7 +61,7 @@ static void vsmp_irq_disable(void) 
}

PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable);



static void vsmp_irq_enable(void)

asmlinkage void vsmp_irq_enable(void)

{

	unsigned long flags = native_save_fl();

arch/x86/xen/irq.c

+4 −4
Original line number Diff line number Diff line
@@ -22,7 +22,7 @@ void xen_force_evtchn_callback(void) 
	(void)HYPERVISOR_xen_version(0, NULL);

}



static unsigned long xen_save_fl(void)

asmlinkage unsigned long xen_save_fl(void)

{

	struct vcpu_info *vcpu;

	unsigned long flags;
@@ -40,7 +40,7 @@ static unsigned long xen_save_fl(void) 
}

PV_CALLEE_SAVE_REGS_THUNK(xen_save_fl);



static void xen_restore_fl(unsigned long flags)

__visible void xen_restore_fl(unsigned long flags)

{

	struct vcpu_info *vcpu;
@@ -62,7 +62,7 @@ static void xen_restore_fl(unsigned long flags) 
}

PV_CALLEE_SAVE_REGS_THUNK(xen_restore_fl);



static void xen_irq_disable(void)

asmlinkage void xen_irq_disable(void)

{

	/* There's a one instruction preempt window here.  We need to

	   make sure we're don't switch CPUs between getting the vcpu
@@ -73,7 +73,7 @@ static void xen_irq_disable(void) 
}

PV_CALLEE_SAVE_REGS_THUNK(xen_irq_disable);



static void xen_irq_enable(void)

asmlinkage void xen_irq_enable(void)

{

	struct vcpu_info *vcpu;

arch/x86/xen/mmu.c

+8 −8
Original line number Diff line number Diff line
@@ -431,7 +431,7 @@ static pteval_t iomap_pte(pteval_t val) 
	return val;

}



static pteval_t xen_pte_val(pte_t pte)

__visible pteval_t xen_pte_val(pte_t pte)

{

	pteval_t pteval = pte.pte;

#if 0
@@ -448,7 +448,7 @@ static pteval_t xen_pte_val(pte_t pte) 
}

PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);



static pgdval_t xen_pgd_val(pgd_t pgd)

__visible pgdval_t xen_pgd_val(pgd_t pgd)

{

	return pte_mfn_to_pfn(pgd.pgd);

}
@@ -479,7 +479,7 @@ void xen_set_pat(u64 pat) 
	WARN_ON(pat != 0x0007010600070106ull);

}



static pte_t xen_make_pte(pteval_t pte)

__visible pte_t xen_make_pte(pteval_t pte)

{

	phys_addr_t addr = (pte & PTE_PFN_MASK);

#if 0
@@ -514,14 +514,14 @@ static pte_t xen_make_pte(pteval_t pte) 
}

PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);



static pgd_t xen_make_pgd(pgdval_t pgd)

__visible 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);



static pmdval_t xen_pmd_val(pmd_t pmd)

__visible pmdval_t xen_pmd_val(pmd_t pmd)

{

	return pte_mfn_to_pfn(pmd.pmd);

}
@@ -580,7 +580,7 @@ static void xen_pmd_clear(pmd_t *pmdp) 
}

#endif	/* CONFIG_X86_PAE */



static pmd_t xen_make_pmd(pmdval_t pmd)

__visible pmd_t xen_make_pmd(pmdval_t pmd)

{

	pmd = pte_pfn_to_mfn(pmd);

	return native_make_pmd(pmd);
@@ -588,13 +588,13 @@ static pmd_t xen_make_pmd(pmdval_t pmd) 
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd);



#if PAGETABLE_LEVELS == 4

static pudval_t xen_pud_val(pud_t pud)

__visible pudval_t xen_pud_val(pud_t pud)

{

	return pte_mfn_to_pfn(pud.pud);

}

PV_CALLEE_SAVE_REGS_THUNK(xen_pud_val);



static pud_t xen_make_pud(pudval_t pud)

__visible pud_t xen_make_pud(pudval_t pud)

{

	pud = pte_pfn_to_mfn(pud);

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