kernel/include/linux/huge_mm.h, branch linux-4.1.y

mm:add KPF_ZERO_PAGE flag for /proc/kpageflags

2015-02-12T01:06:00Z

Add KPF_ZERO_PAGE flag for zero_page, so that userspace processes can detect zero_page in /proc/kpageflags, and then do memory analysis more accurately. Signed-off-by: Yalin Wang Acked-by: Kirill A. Shutemov Cc: Konstantin Khlebnikov Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: convert a few VM_BUG_ON callers to VM_BUG_ON_VMA

2014-10-10T02:25:57Z

Trivially convert a few VM_BUG_ON calls to VM_BUG_ON_VMA to extract more information when they trigger. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Sasha Levin Reviewed-by: Naoya Horiguchi Cc: Kirill A. Shutemov Cc: Konstantin Khlebnikov Cc: Rik van Riel Cc: Mel Gorman Cc: Michal Hocko Cc: Hugh Dickins Cc: Vlastimil Babka Cc: Michel Lespinasse Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: make copy_pte_range static again

2014-08-07T01:01:19Z

Commit 71e3aac0724f ("thp: transparent hugepage core") adds copy_pte_range prototype to huge_mm.h. I'm not sure why (or if) this function have been used outside of memory.c, but it currently isn't. This patch makes copy_pte_range() static again. Signed-off-by: Jerome Marchand Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: close PageTail race

2014-03-04T15:55:47Z

Commit bf6bddf1924e ("mm: introduce compaction and migration for ballooned pages") introduces page_count(page) into memory compaction which dereferences page->first_page if PageTail(page). This results in a very rare NULL pointer dereference on the aforementioned page_count(page). Indeed, anything that does compound_head(), including page_count() is susceptible to racing with prep_compound_page() and seeing a NULL or dangling page->first_page pointer. This patch uses Andrea's implementation of compound_trans_head() that deals with such a race and makes it the default compound_head() implementation. This includes a read memory barrier that ensures that if PageTail(head) is true that we return a head page that is neither NULL nor dangling. The patch then adds a store memory barrier to prep_compound_page() to ensure page->first_page is set. This is the safest way to ensure we see the head page that we are expecting, PageTail(page) is already in the unlikely() path and the memory barriers are unfortunately required. Hugetlbfs is the exception, we don't enforce a store memory barrier during init since no race is possible. Signed-off-by: David Rientjes Cc: Holger Kiehl Cc: Christoph Lameter Cc: Rafael Aquini Cc: Vlastimil Babka Cc: Michal Hocko Cc: Mel Gorman Cc: Andrea Arcangeli Cc: Rik van Riel Cc: "Kirill A. Shutemov" Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: thp: optimize compound_trans_huge

2014-01-22T00:19:43Z

Currently we don't clobber page_tail->first_page during split_huge_page, so compound_trans_head can be set to compound_head without adverse effects, and this mostly optimizes away a smp_rmb. It looks worthwhile to keep around the implementation that doesn't relay on page_tail->first_page not to be clobbered, because it would be necessary if we'll decide to enforce page->private to zero at all times whenever PG_private is not set, also for anonymous pages. For anonymous pages enforcing such an invariant doesn't matter as anonymous pages don't use page->private so we can get away with this microoptimization. Signed-off-by: Andrea Arcangeli Cc: Khalid Aziz Cc: Pravin Shelar Cc: Greg Kroah-Hartman Cc: Ben Hutchings Cc: Christoph Lameter Cc: Johannes Weiner Cc: Mel Gorman Cc: Rik van Riel Cc: Andi Kleen Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm, thp: move ptl taking inside page_check_address_pmd()

2013-11-15T00:32:14Z

With split page table lock we can't know which lock we need to take before we find the relevant pmd. Let's move lock taking inside the function. Signed-off-by: Naoya Horiguchi Signed-off-by: Kirill A. Shutemov Tested-by: Alex Thorlton Cc: Ingo Molnar Cc: "Eric W . Biederman" Cc: "Paul E . McKenney" Cc: Al Viro Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Dave Hansen Cc: Dave Jones Cc: David Howells Cc: Frederic Weisbecker Cc: Johannes Weiner Cc: Kees Cook Cc: Mel Gorman Cc: Michael Kerrisk Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Rik van Riel Cc: Robin Holt Cc: Sedat Dilek Cc: Srikar Dronamraju Cc: Thomas Gleixner Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm, thp: change pmd_trans_huge_lock() to return taken lock

2013-11-15T00:32:14Z

With split ptlock it's important to know which lock pmd_trans_huge_lock() took. This patch adds one more parameter to the function to return the lock. In most places migration to new api is trivial. Exception is move_huge_pmd(): we need to take two locks if pmd tables are different. Signed-off-by: Naoya Horiguchi Signed-off-by: Kirill A. Shutemov Tested-by: Alex Thorlton Cc: Ingo Molnar Cc: "Eric W . Biederman" Cc: "Paul E . McKenney" Cc: Al Viro Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Dave Hansen Cc: Dave Jones Cc: David Howells Cc: Frederic Weisbecker Cc: Johannes Weiner Cc: Kees Cook Cc: Mel Gorman Cc: Michael Kerrisk Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Rik van Riel Cc: Robin Holt Cc: Sedat Dilek Cc: Srikar Dronamraju Cc: Thomas Gleixner Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: consolidate code between handle_mm_fault() and do_huge_pmd_anonymous_page()

2013-09-12T22:38:03Z

do_huge_pmd_anonymous_page() has copy-pasted piece of handle_mm_fault() to handle fallback path. Let's consolidate code back by introducing VM_FAULT_FALLBACK return code. Signed-off-by: Kirill A. Shutemov Acked-by: Hillf Danton Cc: Andrea Arcangeli Cc: Al Viro Cc: Hugh Dickins Cc: Wu Fengguang Cc: Jan Kara Cc: Mel Gorman Cc: Andi Kleen Cc: Matthew Wilcox Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

2013-07-04T17:29:23Z

Pull powerpc updates from Ben Herrenschmidt: "This is the powerpc changes for the 3.11 merge window. In addition to the usual bug fixes and small updates, the main highlights are: - Support for transparent huge pages by Aneesh Kumar for 64-bit server processors. This allows the use of 16M pages as transparent huge pages on kernels compiled with a 64K base page size. - Base VFIO support for KVM on power by Alexey Kardashevskiy - Wiring up of our nvram to the pstore infrastructure, including putting compressed oopses in there by Aruna Balakrishnaiah - Move, rework and improve our "EEH" (basically PCI error handling and recovery) infrastructure. It is no longer specific to pseries but is now usable by the new "powernv" platform as well (no hypervisor) by Gavin Shan. - I fixed some bugs in our math-emu instruction decoding and made it usable to emulate some optional FP instructions on processors with hard FP that lack them (such as fsqrt on Freescale embedded processors). - Support for Power8 "Event Based Branch" facility by Michael Ellerman. This facility allows what is basically "userspace interrupts" for performance monitor events. - A bunch of Transactional Memory vs. Signals bug fixes and HW breakpoint/watchpoint fixes by Michael Neuling. And more ... I appologize in advance if I've failed to highlight something that somebody deemed worth it." * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (156 commits) pstore: Add hsize argument in write_buf call of pstore_ftrace_call powerpc/fsl: add MPIC timer wakeup support powerpc/mpic: create mpic subsystem object powerpc/mpic: add global timer support powerpc/mpic: add irq_set_wake support powerpc/85xx: enable coreint for all the 64bit boards powerpc/8xx: Erroneous double irq_eoi() on CPM IRQ in MPC8xx powerpc/fsl: Enable CONFIG_E1000E in mpc85xx_smp_defconfig powerpc/mpic: Add get_version API both for internal and external use powerpc: Handle both new style and old style reserve maps powerpc/hw_brk: Fix off by one error when validating DAWR region end powerpc/pseries: Support compression of oops text via pstore powerpc/pseries: Re-organise the oops compression code pstore: Pass header size in the pstore write callback powerpc/powernv: Fix iommu initialization again powerpc/pseries: Inform the hypervisor we are using EBB regs powerpc/perf: Add power8 EBB support powerpc/perf: Core EBB support for 64-bit book3s powerpc/perf: Drop MMCRA from thread_struct powerpc/perf: Don't enable if we have zero events ...

mm/thp: define HPAGE_PMD_* constants as BUILD_BUG() if !THP

2013-06-25T23:11:05Z

Currently, HPAGE_PMD_* constans rely on PMD_SHIFT regardless of CONFIG_TRANSPARENT_HUGEPAGE. PMD_SHIFT is not defined everywhere (e.g. arm nommu case). It means we can't use anything like this in generic code: if (PageTransHuge(page)) zero_huge_user(page, 0, HPAGE_PMD_SIZE); else clear_highpage(page); For !THP case, PageTransHuge() is 0 and compiler can eliminate zero_huge_user() call. But it still need to be valid C expression, means HPAGE_PMD_SIZE has to expand to something compiler can understand. Previously, HPAGE_PMD_* were defined to BUILD_BUG() for !THP. Let's come back to it. Signed-off-by: Kirill A. Shutemov Signed-off-by: Andrew Morton Signed-off-by: Benjamin Herrenschmidt