* Gerald Schaefer <gerald.schaefer@xxxxxxxxxx> wrote: > On Sun, 28 Oct 2012 14:10:14 +0100 > Ingo Molnar <mingo@xxxxxxxxxx> wrote: > > > > > There's a related problem on s390: other THP implementations > > have pmd_mknotpresent() while s390 not, resulting in: > > > > mm/huge_memory.c:1543:2: error: implicit declaration of function 'pmd_mknotpresent' > > > > The (untested!) patch below adds the s390 version of this > > method. > > > > Gerald, Martin, did I get the S390 details right? > > The upstream thp patches for s390 fixed that by adding pmdp_invalidate() and > replacing the pmd_mknotpresent() in mm/huge_memory.c, see git commit 46dcde73. > The pmdp_invalidate() is already included linux-next, so it should be ok to > just change mm/huge_memory.c similar to upstream: > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index f1c2679..842b6df 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -1537,8 +1537,7 @@ static int __split_huge_page_map(struct page *page, > * complete. The ptl also protects against concurrent faults due to > * making the pmd not-present. > */ > - set_pmd_at(mm, address, pmd, pmd_mknotpresent(*pmd)); > - flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); > + pmdp_invalidate(vma, address, pmd); > pmd_populate(mm, pmd, pgtable); > ret = 1; > > With this, s390 does not need a pmd_mknotpresent(), and using > set_pmd_at(..., pmd_mknotpresent()) would be wrong on s390 > anyway because we need a flushing operation to change a valid > pmd. Ok, great - so to me it seems that once the two trees are merged there's no extra change needed for s390 - so I dropped the patch. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
