mm: add p[te|md] protnone helpers for use by NUMA balancing

This is a preparatory patch that introduces protnone helpers for automatic
NUMA balancing.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mel Gorman
2015-02-12 14:58:19 -08:00
committed by Linus Torvalds
parent 5d83306213
commit e7bb4b6d16
3 changed files with 52 additions and 0 deletions

View File

@@ -673,6 +673,26 @@ static inline int pmd_trans_unstable(pmd_t *pmd)
#endif
}
#ifndef CONFIG_NUMA_BALANCING
/*
* Technically a PTE can be PROTNONE even when not doing NUMA balancing but
* the only case the kernel cares is for NUMA balancing and is only ever set
* when the VMA is accessible. For PROT_NONE VMAs, the PTEs are not marked
* _PAGE_PROTNONE so by by default, implement the helper as "always no". It
* is the responsibility of the caller to distinguish between PROT_NONE
* protections and NUMA hinting fault protections.
*/
static inline int pte_protnone(pte_t pte)
{
return 0;
}
static inline int pmd_protnone(pmd_t pmd)
{
return 0;
}
#endif /* CONFIG_NUMA_BALANCING */
#ifdef CONFIG_NUMA_BALANCING
/*
* _PAGE_NUMA distinguishes between an unmapped page table entry, an entry that