|From:||Michel Lespinasse <email@example.com>|
|To:||firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com|
|Subject:||[PATCH 0/7] use interval trees for anon rmap|
|Date:||Tue, 4 Sep 2012 02:20:50 -0700|
This patch series applies on top of the previous ones currently queued into Andrew's -mm tree (the rbtree, augmented rbtree and interval tree changes). The goal here is to use interval trees to replace the same_anon_vma linked list, and avoid anon rmap scalability issues when a given process has many vmas linked onto the same anon_vma (as can easily happen when a large vma is broken up into smaller chunks using mprotect or munmap). Patch 1 modifies the generic interval tree implementation and as such, it can be seen as an amendment to the previous patch series which had introduced it. Patch 2 makes the anon_vma locking more strict in vma_adjust(), fixing an issue I noticed when mprotect adjusts the boundary between two vmas and only the second one has an anon_vma assigned. Patch 3 makes the anon_vma locking more strict in move_ptes(). This is a temporary solution to make things simpler while the anon rmap interval tree is being introduced. Patch 7 later relaxes the locking again for the most common cases. Patch 4 implements the anon rmap interval tree and uses it to replace the same_anon_vma linked list. Patch 5 eliminates the error case in vma_address() - the call sites have gotten their vma's from an interval tree so that the desired pgoff (and address) are guaranteed to fall within the vma's interval. Patch 6 adds a build option for the existing DEBUG_MM_RB code, and extends it to check that vma's intervals have not been modified since the vmas were added onto their interval trees. Patch 7 avoids taking rmap locks in move_ptes() during exec() and for the common cases of mremap(). The most common case where mremap() would still take these locks would be if part of a large vma had been previously moved and is now being moved back to its original location. I don't expect this to be very frequent, though, so move_ptes() should be as efficient as it was before patch 3 for all likely cases. Michel Lespinasse (7): mm: interval tree updates mm: fix potential anon_vma locking issue in mprotect() mm anon rmap: remove anon_vma_moveto_tail mm anon rmap: replace same_anon_vma linked list with an interval tree. mm rmap: remove vma_address check for address inside vma mm: add CONFIG_DEBUG_VM_RB build option mm: avoid taking rmap locks in move_ptes() fs/exec.c | 2 +- include/linux/interval_tree_generic.h | 191 ++++++++++++++++++++++++++++ include/linux/interval_tree_tmpl.h | 219 --------------------------------- include/linux/mm.h | 29 ++++- include/linux/rmap.h | 15 ++- kernel/fork.c | 7 +- lib/Kconfig.debug | 9 ++ lib/interval_tree.c | 15 +-- mm/huge_memory.c | 9 +- mm/interval_tree.c | 109 ++++++++++++----- mm/ksm.c | 9 +- mm/memory-failure.c | 5 +- mm/mmap.c | 100 +++++++++++----- mm/mremap.c | 65 ++++++---- mm/rmap.c | 117 +++++------------- 15 files changed, 484 insertions(+), 417 deletions(-) create mode 100644 include/linux/interval_tree_generic.h delete mode 100644 include/linux/interval_tree_tmpl.h -- 188.8.131.52 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to firstname.lastname@example.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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