UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

powerpc/THP: Enable THP on PPC64 

We enable only if the we support 16MB page size.

Reviewed-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Aneesh Kumar K.V 2013-06-20 14:30:26 +05:30 committed by Benjamin Herrenschmidt
parent d8e355a20f
commit 437d496457
2 changed files with 30 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/powerpc/include/asm/pgtable-ppc64.h
View File

@ -444,8 +444,7 @@ static inline int pmd_trans_splitting(pmd_t pmd)
return 0;
}
/* We will enable it in the last patch */
#define has_transparent_hugepage() 0
extern int has_transparent_hugepage(void);
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
static inline pte_t pmd_pte(pmd_t pmd)

29
arch/powerpc/mm/pgtable_64.c
View File

@ -831,4 +831,33 @@ pmd_t pmdp_get_and_clear(struct mm_struct *mm,
memset(pgtable, 0, PTE_FRAG_SIZE);
return old_pmd;
}
int has_transparent_hugepage(void)
{
if (!mmu_has_feature(MMU_FTR_16M_PAGE))
return 0;
/*
* We support THP only if PMD_SIZE is 16MB.
*/
if (mmu_psize_defs[MMU_PAGE_16M].shift != PMD_SHIFT)
return 0;
/*
* We need to make sure that we support 16MB hugepage in a segement
* with base page size 64K or 4K. We only enable THP with a PAGE_SIZE
* of 64K.
*/
/*
* If we have 64K HPTE, we will be using that by default
*/
if (mmu_psize_defs[MMU_PAGE_64K].shift &&
(mmu_psize_defs[MMU_PAGE_64K].penc[MMU_PAGE_16M] == -1))
return 0;
/*
* Ok we only have 4K HPTE
*/
if (mmu_psize_defs[MMU_PAGE_4K].penc[MMU_PAGE_16M] == -1)
return 0;
return 1;
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */