From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Aneesh Kumar K.V" Subject: [PATCH -V1 0/9] hugetlbfs: Add cgroup resource controller for hugetlbfs Date: Mon, 20 Feb 2012 16:51:33 +0530 Message-ID: <1329736902-26870-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Return-path: Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-mm@kvack.org, mgorman@suse.de, kamezawa.hiroyu@jp.fujitsu.com, dhillf@gmail.com, aarcange@redhat.com, mhocko@suse.cz, akpm@linux-foundation.org, hannes@cmpxchg.org Cc: linux-kernel@vger.kernel.org, cgroups@kernel.org Hi, This patchset implements a cgroup resource controller for HugeTLB pages. 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 quota limit the number of huge pages that can allocated per superblock. For shared mapping we track the region mapped by a task along with the hugetlb cgroup. We keep the hugetlb cgroup charged even after the task that did mmap(2) exit. The uncharge happens during truncate. For Private mapping we charge and uncharge from the current task cgroup. A sample strace output for an application doing malloc with hugectl is given below. libhugetlbfs will fallback to normal pagesize if the HugeTLB mmap fails. open("/mnt/libhugetlbfs.tmp.uhLMgy", O_RDWR|O_CREAT|O_EXCL, 0600) = 3 unlink("/mnt/libhugetlbfs.tmp.uhLMgy") = 0 ......... mmap(0x20000000000, 50331648, PROT_READ|PROT_WRITE, MAP_PRIVATE, 3, 0) = -1 ENOMEM (Cannot allocate memory) write(2, "libhugetlbfs", 12libhugetlbfs) = 12 write(2, ": WARNING: New heap segment map" .... mmap(NULL, 42008576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xfff946c0000 .... Changes from RFC post: * Added support for HugeTLB cgroup hierarchy * Added support for task migration * Added documentation patch * Other Bug fixes -aneesh