linux_dsm_epyc7002/include/asm-generic/pgalloc.h
Nicholas Piggin 13224794cb mm: remove quicklist page table caches
Patch series "mm: remove quicklist page table caches".

A while ago Nicholas proposed to remove quicklist page table caches [1].

I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.

[1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com

This patch (of 3):

Remove page table allocator "quicklists".  These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.

The numbers in the initial commit look interesting but probably don't
apply anymore.  If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.

Also it might be better to instead make more general improvements to page
allocator if this is still so slow.

Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:09 -07:00

108 lines
2.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_GENERIC_PGALLOC_H
#define __ASM_GENERIC_PGALLOC_H
#ifdef CONFIG_MMU
#define GFP_PGTABLE_KERNEL (GFP_KERNEL | __GFP_ZERO)
#define GFP_PGTABLE_USER (GFP_PGTABLE_KERNEL | __GFP_ACCOUNT)
/**
* __pte_alloc_one_kernel - allocate a page for PTE-level kernel page table
* @mm: the mm_struct of the current context
*
* This function is intended for architectures that need
* anything beyond simple page allocation.
*
* Return: pointer to the allocated memory or %NULL on error
*/
static inline pte_t *__pte_alloc_one_kernel(struct mm_struct *mm)
{
return (pte_t *)__get_free_page(GFP_PGTABLE_KERNEL);
}
#ifndef __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
/**
* pte_alloc_one_kernel - allocate a page for PTE-level kernel page table
* @mm: the mm_struct of the current context
*
* Return: pointer to the allocated memory or %NULL on error
*/
static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
{
return __pte_alloc_one_kernel(mm);
}
#endif
/**
* pte_free_kernel - free PTE-level kernel page table page
* @mm: the mm_struct of the current context
* @pte: pointer to the memory containing the page table
*/
static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
{
free_page((unsigned long)pte);
}
/**
* __pte_alloc_one - allocate a page for PTE-level user page table
* @mm: the mm_struct of the current context
* @gfp: GFP flags to use for the allocation
*
* Allocates a page and runs the pgtable_page_ctor().
*
* This function is intended for architectures that need
* anything beyond simple page allocation or must have custom GFP flags.
*
* Return: `struct page` initialized as page table or %NULL on error
*/
static inline pgtable_t __pte_alloc_one(struct mm_struct *mm, gfp_t gfp)
{
struct page *pte;
pte = alloc_page(gfp);
if (!pte)
return NULL;
if (!pgtable_page_ctor(pte)) {
__free_page(pte);
return NULL;
}
return pte;
}
#ifndef __HAVE_ARCH_PTE_ALLOC_ONE
/**
* pte_alloc_one - allocate a page for PTE-level user page table
* @mm: the mm_struct of the current context
*
* Allocates a page and runs the pgtable_page_ctor().
*
* Return: `struct page` initialized as page table or %NULL on error
*/
static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
{
return __pte_alloc_one(mm, GFP_PGTABLE_USER);
}
#endif
/*
* Should really implement gc for free page table pages. This could be
* done with a reference count in struct page.
*/
/**
* pte_free - free PTE-level user page table page
* @mm: the mm_struct of the current context
* @pte_page: the `struct page` representing the page table
*/
static inline void pte_free(struct mm_struct *mm, struct page *pte_page)
{
pgtable_page_dtor(pte_page);
__free_page(pte_page);
}
#endif /* CONFIG_MMU */
#endif /* __ASM_GENERIC_PGALLOC_H */