mm: numa: avoid unnecessary TLB flushes when setting NUMA hinting entries
If a PTE or PMD is already marked NUMA when scanning to mark entries for NUMA hinting then it is not necessary to update the entry and incur a TLB flush penalty. Avoid the avoidhead where possible. Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Rik van Riel <riel@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
c0e7cad9f2
commit
10c1045f28
|
@ -1493,12 +1493,14 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
|
|||
return 0;
|
||||
}
|
||||
|
||||
ret = 1;
|
||||
entry = pmdp_get_and_clear_notify(mm, addr, pmd);
|
||||
entry = pmd_modify(entry, newprot);
|
||||
ret = HPAGE_PMD_NR;
|
||||
set_pmd_at(mm, addr, pmd, entry);
|
||||
BUG_ON(pmd_write(entry));
|
||||
if (!prot_numa || !pmd_protnone(*pmd)) {
|
||||
ret = 1;
|
||||
entry = pmdp_get_and_clear_notify(mm, addr, pmd);
|
||||
entry = pmd_modify(entry, newprot);
|
||||
ret = HPAGE_PMD_NR;
|
||||
set_pmd_at(mm, addr, pmd, entry);
|
||||
BUG_ON(pmd_write(entry));
|
||||
}
|
||||
spin_unlock(ptl);
|
||||
}
|
||||
|
||||
|
|
|
@ -86,6 +86,10 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
|
|||
page = vm_normal_page(vma, addr, oldpte);
|
||||
if (!page || PageKsm(page))
|
||||
continue;
|
||||
|
||||
/* Avoid TLB flush if possible */
|
||||
if (pte_protnone(oldpte))
|
||||
continue;
|
||||
}
|
||||
|
||||
ptent = ptep_modify_prot_start(mm, addr, pte);
|
||||
|
|
Loading…
Reference in New Issue