mm: softdirty: clear VM_SOFTDIRTY flag inside clear_refs_write() instead of clear_soft_dirty()

clear_refs_write() is called earlier than clear_soft_dirty() and it is
more natural to clear VM_SOFTDIRTY (which belongs to VMA entry but not
PTEs) that early instead of clearing it a way deeper inside call chain.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Cyrill Gorcunov 2014-06-04 16:06:43 -07:00 committed by Linus Torvalds
parent b43790eedd
commit c86c97ff42

View file

@ -737,9 +737,6 @@ static inline void clear_soft_dirty(struct vm_area_struct *vma,
ptent = pte_file_clear_soft_dirty(ptent);
}
if (vma->vm_flags & VM_SOFTDIRTY)
vma->vm_flags &= ~VM_SOFTDIRTY;
set_pte_at(vma->vm_mm, addr, pte, ptent);
#endif
}
@ -807,8 +804,9 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
if (type == CLEAR_REFS_SOFT_DIRTY) {
soft_dirty_cleared = true;
pr_warn_once("The pagemap bits 55-60 has changed their meaning! "
"See the linux/Documentation/vm/pagemap.txt for details.\n");
pr_warn_once("The pagemap bits 55-60 has changed their meaning!"
" See the linux/Documentation/vm/pagemap.txt for "
"details.\n");
}
task = get_proc_task(file_inode(file));
@ -839,11 +837,17 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
*
* Writing 3 to /proc/pid/clear_refs only affects file
* mapped pages.
*
* Writing 4 to /proc/pid/clear_refs affects all pages.
*/
if (type == CLEAR_REFS_ANON && vma->vm_file)
continue;
if (type == CLEAR_REFS_MAPPED && !vma->vm_file)
continue;
if (type == CLEAR_REFS_SOFT_DIRTY) {
if (vma->vm_flags & VM_SOFTDIRTY)
vma->vm_flags &= ~VM_SOFTDIRTY;
}
walk_page_range(vma->vm_start, vma->vm_end,
&clear_refs_walk);
}