On Thu, 28 Apr 2016 07:46:07 -0600 Jonathan Corbet <corbet@xxxxxxx> wrote: > On Thu, 28 Apr 2016 07:31:43 -0600 > Jonathan Corbet <corbet@xxxxxxx> wrote: > > > On Mon, 25 Apr 2016 07:37:05 +0100 > > Eric Engestrom <eric@xxxxxxxxxxxx> wrote: > > > > > Documentation/vm/transhuge.txt | 6 +++--- > > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > Applied to the docs tree, thanks. > > Actually, I've just unapplied this one; it conflicts against changes in > Andrew's tree and, thus, linux-next. Andrew, maybe you'd like to take it > on top of what you have now? Sure. That Documentation/vm/transhuge.txt paragraph isn't in great shape so I gave it some extra help. From: Eric Engestrom <eric@xxxxxxxxxxxx> Subject: Documentation: vm: fix spelling mistakes Signed-off-by: Eric Engestrom <eric@xxxxxxxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/vm/transhuge.txt | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff -puN Documentation/vm/transhuge.txt~documentation-vm-fix-spelling-mistakes Documentation/vm/transhuge.txt --- a/Documentation/vm/transhuge.txt~documentation-vm-fix-spelling-mistakes +++ a/Documentation/vm/transhuge.txt @@ -340,7 +340,7 @@ unaffected. libhugetlbfs will also work == Graceful fallback == -Code walking pagetables but unware about huge pmds can simply call +Code walking pagetables but unaware about huge pmds can simply call split_huge_pmd(vma, pmd, addr) where the pmd is the one returned by pmd_offset. It's trivial to make the code transparent hugepage aware by just grepping for "pmd_offset" and adding split_huge_pmd where @@ -414,7 +414,7 @@ tracking. The alternative is alter ->_ma map/unmap of the whole compound page. We set PG_double_map when a PMD of the page got split for the first time, -but still have PMD mapping. The addtional references go away with last +but still have PMD mapping. The additional references go away with last compound_mapcount. split_huge_page internally has to distribute the refcounts in the head @@ -432,10 +432,10 @@ page->_mapcount. We safe against physical memory scanners too: the only legitimate way scanner can get reference to a page is get_page_unless_zero(). -All tail pages has zero ->_refcount until atomic_add(). It prevent scanner -from geting reference to tail page up to the point. After the atomic_add() -we don't care about ->_refcount value. We already known how many references -with should uncharge from head page. +All tail pages have zero ->_refcount until atomic_add(). This prevents the +scanner from getting a reference to the tail page up to that point. After the +atomic_add() we don't care about the ->_refcount value. We already known how +many references should be uncharged from the head page. For head page get_page_unless_zero() will succeed and we don't mind. It's clear where reference should go after split: it will stay on head page. _ -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
