Commit c8db8c26 authored by Li kunyu's avatar Li kunyu Committed by Andrew Morton
Browse files

mm: functions may simplify the use of return values 

p4d_clear_huge may be optimized for void return type and function usage. 
vunmap_p4d_range function saves a few steps here.

Link: https://lkml.kernel.org/r/20220507150630.90399-1-kunyu@nfschina.com


Signed-off-by: default avatarLi kunyu <kunyu@nfschina.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 3fee229a

arch/x86/mm/pgtable.c

+1 −2
Original line number Diff line number Diff line
@@ -686,9 +686,8 @@ int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot) 
 *

 * No 512GB pages yet -- always return 0

 */

int p4d_clear_huge(p4d_t *p4d)

void p4d_clear_huge(p4d_t *p4d)

{

	return 0;

}

#endif

include/linux/pgtable.h

+3 −9
Original line number Diff line number Diff line
@@ -1448,16 +1448,13 @@ static inline int pmd_protnone(pmd_t pmd) 


#ifndef __PAGETABLE_P4D_FOLDED

int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot);

int p4d_clear_huge(p4d_t *p4d);

void p4d_clear_huge(p4d_t *p4d);

#else

static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)

{

	return 0;

}

static inline int p4d_clear_huge(p4d_t *p4d)

{

	return 0;

}

static inline void p4d_clear_huge(p4d_t *p4d) { }

#endif /* !__PAGETABLE_P4D_FOLDED */



int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot);
@@ -1480,10 +1477,7 @@ static inline int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot) 
{

	return 0;

}

static inline int p4d_clear_huge(p4d_t *p4d)

{

	return 0;

}

static inline void p4d_clear_huge(p4d_t *p4d) { }

static inline int pud_clear_huge(pud_t *pud)

{

	return 0;

mm/vmalloc.c

+2 −5
Original line number Diff line number Diff line
@@ -389,18 +389,15 @@ static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, 
{

	p4d_t *p4d;

	unsigned long next;

	int cleared;



	p4d = p4d_offset(pgd, addr);

	do {

		next = p4d_addr_end(addr, end);



		cleared = p4d_clear_huge(p4d);

		if (cleared || p4d_bad(*p4d))

		p4d_clear_huge(p4d);

		if (p4d_bad(*p4d))

			*mask |= PGTBL_P4D_MODIFIED;



		if (cleared)

			continue;

		if (p4d_none_or_clear_bad(p4d))

			continue;

		vunmap_pud_range(p4d, addr, next, mask);