The patch titled ksm: clean up obsolete references has been added to the -mm tree. Its filename is ksm-clean-up-obsolete-references.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: ksm: clean up obsolete references From: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx> A few cleanups, given the munlock fix: the comment on ksm_test_exit() no longer applies, and it can be made private to ksm.c; there's no more reference to mmu_gather or tlb.h, and mmap.c doesn't need ksm.h. Signed-off-by: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx> Acked-by: Izik Eidus <ieidus@xxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/ksm.h | 20 -------------------- mm/ksm.c | 14 +++++++++++++- mm/mmap.c | 1 - 3 files changed, 13 insertions(+), 22 deletions(-) diff -puN include/linux/ksm.h~ksm-clean-up-obsolete-references include/linux/ksm.h --- a/include/linux/ksm.h~ksm-clean-up-obsolete-references +++ a/include/linux/ksm.h @@ -12,8 +12,6 @@ #include <linux/sched.h> #include <linux/vmstat.h> -struct mmu_gather; - #ifdef CONFIG_KSM int ksm_madvise(struct vm_area_struct *vma, unsigned long start, unsigned long end, int advice, unsigned long *vm_flags); @@ -27,19 +25,6 @@ static inline int ksm_fork(struct mm_str return 0; } -/* - * For KSM to handle OOM without deadlock when it's breaking COW in a - * likely victim of the OOM killer, exit_mmap() has to serialize with - * ksm_exit() after freeing mm's pages but before freeing its page tables. - * That leaves a window in which KSM might refault pages which have just - * been finally unmapped: guard against that with ksm_test_exit(), and - * use it after getting mmap_sem in ksm.c, to check if mm is exiting. - */ -static inline bool ksm_test_exit(struct mm_struct *mm) -{ - return atomic_read(&mm->mm_users) == 0; -} - static inline void ksm_exit(struct mm_struct *mm) { if (test_bit(MMF_VM_MERGEABLE, &mm->flags)) @@ -79,11 +64,6 @@ static inline int ksm_fork(struct mm_str return 0; } -static inline bool ksm_test_exit(struct mm_struct *mm) -{ - return 0; -} - static inline void ksm_exit(struct mm_struct *mm) { } diff -puN mm/ksm.c~ksm-clean-up-obsolete-references mm/ksm.c --- a/mm/ksm.c~ksm-clean-up-obsolete-references +++ a/mm/ksm.c @@ -32,7 +32,6 @@ #include <linux/mmu_notifier.h> #include <linux/ksm.h> -#include <asm/tlb.h> #include <asm/tlbflush.h> /* @@ -285,6 +284,19 @@ static inline int in_stable_tree(struct } /* + * ksmd, and unmerge_and_remove_all_rmap_items(), must not touch an mm's + * page tables after it has passed through ksm_exit() - which, if necessary, + * takes mmap_sem briefly to serialize against them. ksm_exit() does not set + * a special flag: they can just back out as soon as mm_users goes to zero. + * ksm_test_exit() is used throughout to make this test for exit: in some + * places for correctness, in some places just to avoid unnecessary work. + */ +static inline bool ksm_test_exit(struct mm_struct *mm) +{ + return atomic_read(&mm->mm_users) == 0; +} + +/* * We use break_ksm to break COW on a ksm page: it's a stripped down * * if (get_user_pages(current, mm, addr, 1, 1, 1, &page, NULL) == 1) diff -puN mm/mmap.c~ksm-clean-up-obsolete-references mm/mmap.c --- a/mm/mmap.c~ksm-clean-up-obsolete-references +++ a/mm/mmap.c @@ -27,7 +27,6 @@ #include <linux/mount.h> #include <linux/mempolicy.h> #include <linux/rmap.h> -#include <linux/ksm.h> #include <linux/mmu_notifier.h> #include <linux/perf_counter.h> _ Patches currently in -mm which might be from hugh.dickins@xxxxxxxxxxxxx are linux-next.patch acpi-fix-null-bug-for-hid-uid-string-2.patch vfs-optimize-touch_time-too-fix.patch fs-new-truncate-helpers.patch fs-use-new-truncate-helpers.patch fs-introduce-new-truncate-sequence.patch fs-convert-simple-fs-to-new-truncate.patch tmpfs-convert-to-use-the-new-truncate-convention.patch ext2-convert-to-use-the-new-truncate-convention.patch fat-convert-to-use-the-new-truncate-convention.patch btrfs-convert-to-use-the-new-truncate-convention.patch jfs-convert-to-use-the-new-truncate-convention.patch udf-convert-to-use-the-new-truncate-convention.patch minix-convert-to-use-the-new-truncate-convention.patch mm-oom-analysis-add-shmem-vmstat.patch ksm-add-mmu_notifier-set_pte_at_notify.patch ksm-first-tidy-up-madvise_vma.patch ksm-define-madv_mergeable-and-madv_unmergeable.patch ksm-the-mm-interface-to-ksm.patch ksm-no-debug-in-page_dup_rmap.patch ksm-identify-pageksm-pages.patch ksm-kernel-samepage-merging.patch ksm-prevent-mremap-move-poisoning.patch ksm-change-copyright-message.patch ksm-change-ksm-nice-level-to-be-5.patch ksm-rename-kernel_pages_allocated.patch ksm-move-pages_sharing-updates.patch ksm-pages_unshared-and-pages_volatile.patch ksm-break-cow-once-unshared.patch ksm-keep-quiet-while-list-empty.patch ksm-five-little-cleanups.patch ksm-fix-endless-loop-on-oom.patch ksm-distribute-remove_mm_from_lists.patch ksm-fix-oom-deadlock.patch ksm-fix-deadlock-with-munlock-in-exit_mmap.patch ksm-sysfs-and-defaults.patch ksm-add-some-documentation.patch ksm-remove-vm_mergeable_flags.patch ksm-clean-up-obsolete-references.patch ksm-unmerge-is-an-origin-of-ooms.patch ksm-mremap-use-err-from-ksm_madvise.patch mm-add_to_swap_cache-must-not-sleep.patch mm-add_to_swap_cache-does-not-return-eexist.patch mm-includecheck-fix-for-mm-shmemc.patch mm-introduce-page_lru_base_type-fix.patch mm-replace-various-uses-of-num_physpages-by-totalram_pages.patch hugetlbfs-allow-the-creation-of-files-suitable-for-map_private-on-the-vfs-internal-mount.patch hugetlb-add-map_hugetlb-for-mmaping-pseudo-anonymous-huge-page-regions.patch hugetlb-add-map_hugetlb-example.patch getrusage-fill-ru_maxrss-value.patch getrusage-fill-ru_maxrss-value-update.patch ramfs-move-ramfs_magic-to-include-linux-magich.patch memory-controller-soft-limit-organize-cgroups-v9-fix.patch prio_tree-debugging-patch.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html