user/sven/linux.git/include/linux/huge_mm.h, branch v3.0-rc5

mm: convert anon_vma->lock to a mutex

2011-05-25T15:39:19Z

Straightforward conversion of anon_vma->lock to a mutex. Signed-off-by: Peter Zijlstra Acked-by: Hugh Dickins Reviewed-by: KOSAKI Motohiro Cc: Benjamin Herrenschmidt Cc: David Miller Cc: Martin Schwidefsky Cc: Russell King Cc: Paul Mundt Cc: Jeff Dike Cc: Richard Weinberger Cc: Tony Luck Cc: KAMEZAWA Hiroyuki Cc: Mel Gorman Cc: Nick Piggin Cc: Namhyung Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: thp: fix /dev/zero MAP_PRIVATE and vm_flags cleanups

2011-04-28T18:28:20Z

The huge_memory.c THP page fault was allowed to run if vm_ops was null (which would succeed for /dev/zero MAP_PRIVATE, as the f_op->mmap wouldn't setup a special vma->vm_ops and it would fallback to regular anonymous memory) but other THP logics weren't fully activated for vmas with vm_file not NULL (/dev/zero has a not NULL vma->vm_file). So this removes the vm_file checks so that /dev/zero also can safely use THP (the other albeit safer approach to fix this bug would have been to prevent the THP initial page fault to run if vm_file was set). After removing the vm_file checks, this also makes huge_memory.c stricter in khugepaged for the DEBUG_VM=y case. It doesn't replace the vm_file check with a is_pfn_mapping check (but it keeps checking for VM_PFNMAP under VM_BUG_ON) because for a is_cow_mapping() mapping VM_PFNMAP should only be allowed to exist before the first page fault, and in turn when vma->anon_vma is null (so preventing khugepaged registration). So I tend to think the previous comment saying if vm_file was set, VM_PFNMAP might have been set and we could still be registered in khugepaged (despite anon_vma was not NULL to be registered in khugepaged) was too paranoid. The is_linear_pfn_mapping check is also I think superfluous (as described by comment) but under DEBUG_VM it is safe to stay. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=33682 Signed-off-by: Andrea Arcangeli Reported-by: Caspar Zhang Acked-by: Mel Gorman Acked-by: Rik van Riel Cc: [2.6.38.x] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: prevent hugepages during args/env copying into the user stack

2011-02-15T23:21:11Z

Transparent hugepages can only be created if rmap is fully functional. So we must prevent hugepages to be created while is_vma_temporary_stack() is true. This also optmizes away some harmless but unnecessary setting of khugepaged_scan.address and it switches some BUG_ON to VM_BUG_ON. Signed-off-by: Andrea Arcangeli Acked-by: Rik van Riel Signed-off-by: Linus Torvalds

thp: add compound_trans_head() helper

2011-01-14T01:32:48Z

Cleanup some code with common compound_trans_head helper. Signed-off-by: Andrea Arcangeli Cc: Hugh Dickins Cc: Johannes Weiner Cc: Marcelo Tosatti Cc: Avi Kivity Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: khugepaged: make khugepaged aware about madvise

2011-01-14T01:32:47Z

MADV_HUGEPAGE and MADV_NOHUGEPAGE were fully effective only if run after mmap and before touching the memory. While this is enough for most usages, it's little effort to make madvise more dynamic at runtime on an existing mapping by making khugepaged aware about madvise. MADV_HUGEPAGE: register in khugepaged immediately without waiting a page fault (that may not ever happen if all pages are already mapped and the "enabled" knob was set to madvise during the initial page faults). MADV_NOHUGEPAGE: skip vmas marked VM_NOHUGEPAGE in khugepaged to stop collapsing pages where not needed. [akpm@linux-foundation.org: tweak comment] Signed-off-by: Andrea Arcangeli Cc: Michael Kerrisk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: madvise(MADV_NOHUGEPAGE)

2011-01-14T01:32:47Z

Add madvise MADV_NOHUGEPAGE to mark regions that are not important to be hugepage backed. Return -EINVAL if the vma is not of an anonymous type, or the feature isn't built into the kernel. Never silently return success. Signed-off-by: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: fix anon memory statistics with transparent hugepages

2011-01-14T01:32:46Z

Count each transparent hugepage as HPAGE_PMD_NR pages in the LRU statistics, so the Active(anon) and Inactive(anon) statistics in /proc/meminfo are correct. Signed-off-by: Rik van Riel Signed-off-by: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: avoid breaking huge pmd invariants in case of vma_adjust failures

2011-01-14T01:32:45Z

An huge pmd can only be mapped if the corresponding 2M virtual range is fully contained in the vma. At times the VM calls split_vma twice, if the first split_vma succeeds and the second fail, the first split_vma remains in effect and it's not rolled back. For split_vma or vma_adjust to fail an allocation failure is needed so it's a very unlikely event (the out of memory killer would normally fire before any allocation failure is visible to kernel and userland and if an out of memory condition happens it's unlikely to happen exactly here). Nevertheless it's safer to ensure that no huge pmd can be left around if the vma is adjusted in a way that can't fit hugepages anymore at the new vm_start/vm_end address. Signed-off-by: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: mprotect: transparent huge page support

2011-01-14T01:32:44Z

Natively handle huge pmds when changing page tables on behalf of mprotect(). I left out update_mmu_cache() because we do not need it on x86 anyway but more importantly the interface works on ptes, not pmds. Signed-off-by: Johannes Weiner Signed-off-by: Andrea Arcangeli Reviewed-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

thp: mincore transparent hugepage support

2011-01-14T01:32:44Z

Handle transparent huge page pmd entries natively instead of splitting them into subpages. Signed-off-by: Johannes Weiner Signed-off-by: Andrea Arcangeli Reviewed-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds