diff options
| author | Ingo Molnar <mingo@elte.hu> | 2009-10-06 15:02:30 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-10-06 15:02:34 +0200 |
| commit | d9b2002c406011164f245de7a81304625989f1c9 (patch) | |
| tree | a2bb74773cd1409acbec5eb2fbba2ae9889d55e8 /mm/mremap.c | |
| parent | c3b32fcbc7f4fd9a9b84718b991b175b0fd53f8c (diff) | |
| parent | 906010b2134e14a2e377decbadd357b3d0ab9c6a (diff) | |
Merge branch 'perf/urgent' into perf/core
Merge reason: Upcoming patch is dependent on a fix in perf/urgent.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'mm/mremap.c')
| -rw-r--r-- | mm/mremap.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/mm/mremap.c b/mm/mremap.c index a39b7b91be4..97bff254771 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -11,6 +11,7 @@ #include <linux/hugetlb.h> #include <linux/slab.h> #include <linux/shm.h> +#include <linux/ksm.h> #include <linux/mman.h> #include <linux/swap.h> #include <linux/capability.h> @@ -85,8 +86,8 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd, if (vma->vm_file) { /* * Subtle point from Rajesh Venkatasubramanian: before - * moving file-based ptes, we must lock vmtruncate out, - * since it might clean the dst vma before the src vma, + * moving file-based ptes, we must lock truncate_pagecache + * out, since it might clean the dst vma before the src vma, * and we propagate stale pages into the dst afterward. */ mapping = vma->vm_file->f_mapping; @@ -174,6 +175,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, unsigned long excess = 0; unsigned long hiwater_vm; int split = 0; + int err; /* * We'd prefer to avoid failure later on in do_munmap: @@ -182,6 +184,18 @@ static unsigned long move_vma(struct vm_area_struct *vma, if (mm->map_count >= sysctl_max_map_count - 3) return -ENOMEM; + /* + * Advise KSM to break any KSM pages in the area to be moved: + * it would be confusing if they were to turn up at the new + * location, where they happen to coincide with different KSM + * pages recently unmapped. But leave vma->vm_flags as it was, + * so KSM can come around to merge on vma and new_vma afterwards. + */ + err = ksm_madvise(vma, old_addr, old_addr + old_len, + MADV_UNMERGEABLE, &vm_flags); + if (err) + return err; + new_pgoff = vma->vm_pgoff + ((old_addr - vma->vm_start) >> PAGE_SHIFT); new_vma = copy_vma(&vma, new_addr, new_len, new_pgoff); if (!new_vma) |