On Thu, 1 Mar 2012 14:40:29 -0800, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > On Thu, 1 Mar 2012 14:46:11 +0530 > "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx> wrote: > > > This patchset implements a memory controller extension to control > > HugeTLB allocations. It is similar to the existing hugetlb quota > > support in that, the limit is enforced at mmap(2) time and not at > > fault time. HugeTLB's quota mechanism limits the number of huge pages > > that can allocated per superblock. > > > > For shared mappings we track the regions mapped by a task along with the > > memcg. We keep the memory controller charged even after the task > > that did mmap(2) exits. Uncharge happens during truncate. For Private > > mappings we charge and uncharge from the current task cgroup. > > I haven't begin to get my head around this yet, but I'd like to draw > your attention to https://lkml.org/lkml/2012/2/15/548. Hmm that's really serious bug. > That fix has > been hanging around for a while, but I haven't done anything with it > yet because I don't like its additional blurring of the separation > between hugetlb core code and hugetlbfs. I want to find time to sit > down and see if the fix can be better architected but haven't got > around to that yet. > > I expect that your patches will conflict at least mechanically with > David's, which is not a big issue. But I wonder whether your patches > will copy the same bug into other places, and whether you can think of > a tidier way of addressing the bug which David is seeing? > I will go through the implementation again and make sure the problem explained by David doesn't happen in the new code path added by the patch series. Thanks -aneesh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>