From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 30 Jul 2008 01:41:39 -0700 From: Andrew Morton Subject: Re: [RFC] [PATCH 0/5 V2] Huge page backed user-space stacks Message-Id: <20080730014139.39b3edc5.akpm@linux-foundation.org> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Eric Munson Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, libhugetlbfs-devel@lists.sourceforge.net List-ID: On Mon, 28 Jul 2008 12:17:10 -0700 Eric Munson wrote: > Certain workloads benefit if their data or text segments are backed by > huge pages. The stack is no exception to this rule but there is no > mechanism currently that allows the backing of a stack reliably with > huge pages. Doing this from userspace is excessively messy and has some > awkward restrictions. Particularly on POWER where 256MB of address space > gets wasted if the stack is setup there. > > This patch stack introduces a personality flag that indicates the kernel > should setup the stack as a hugetlbfs-backed region. A userspace utility > may set this flag then exec a process whose stack is to be backed by > hugetlb pages. > > Eric Munson (5): > Align stack boundaries based on personality > Add shared and reservation control to hugetlb_file_setup > Split boundary checking from body of do_munmap > Build hugetlb backed process stacks > [PPC] Setup stack memory segment for hugetlb pages > > arch/powerpc/mm/hugetlbpage.c | 6 + > arch/powerpc/mm/slice.c | 11 ++ > fs/exec.c | 209 ++++++++++++++++++++++++++++++++++++++--- > fs/hugetlbfs/inode.c | 52 +++++++---- > include/asm-powerpc/hugetlb.h | 3 + > include/linux/hugetlb.h | 22 ++++- > include/linux/mm.h | 1 + > include/linux/personality.h | 3 + > ipc/shm.c | 2 +- > mm/mmap.c | 11 ++- > 10 files changed, 284 insertions(+), 36 deletions(-) That all looks surprisingly straightforward. Might there exist an x86 port which people can play with? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org