The patch titled
Subject: task_mmu: convert to vma iterator
has been added to the -mm mm-unstable branch. Its filename is
task_mmu-convert-to-vma-iterator.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/task_mmu-convert-to-vma-iterator.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
Subject: task_mmu: convert to vma iterator
Date: Fri, 20 Jan 2023 11:26:22 -0500
Use the vma iterator so that the iterator can be invalidated or updated to
avoid each caller doing so.
Update the comments to how the vma iterator works. The vma iterator will
keep track of the last vm_end and start the search from vm_end + 1.
Link: https://lkml.kernel.org/r/20230120162650.984577-22-Liam.Howlett@xxxxxxxxxx
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/fs/proc/task_mmu.c~task_mmu-convert-to-vma-iterator
+++ a/fs/proc/task_mmu.c
@@ -892,7 +892,7 @@ static int show_smaps_rollup(struct seq_
struct vm_area_struct *vma;
unsigned long vma_start = 0, last_vma_end = 0;
int ret = 0;
- MA_STATE(mas, &mm->mm_mt, 0, 0);
+ VMA_ITERATOR(vmi, mm, 0);
priv->task = get_proc_task(priv->inode);
if (!priv->task)
@@ -910,7 +910,7 @@ static int show_smaps_rollup(struct seq_
goto out_put_mm;
hold_task_mempolicy(priv);
- vma = mas_find(&mas, ULONG_MAX);
+ vma = vma_next(&vmi);
if (unlikely(!vma))
goto empty_set;
@@ -925,7 +925,7 @@ static int show_smaps_rollup(struct seq_
* access it for write request.
*/
if (mmap_lock_is_contended(mm)) {
- mas_pause(&mas);
+ vma_iter_invalidate(&vmi);
mmap_read_unlock(mm);
ret = mmap_read_lock_killable(mm);
if (ret) {
@@ -950,31 +950,31 @@ static int show_smaps_rollup(struct seq_
*
* 1) VMA2 is freed, but VMA3 exists:
*
- * find_vma(mm, 16k - 1) will return VMA3.
+ * vma_next(vmi) will return VMA3.
* In this case, just continue from VMA3.
*
* 2) VMA2 still exists:
*
- * find_vma(mm, 16k - 1) will return VMA2.
- * Iterate the loop like the original one.
+ * vma_next(vmi) will return VMA3.
+ * In this case, just continue from VMA3.
*
* 3) No more VMAs can be found:
*
- * find_vma(mm, 16k - 1) will return NULL.
+ * vma_next(vmi) will return NULL.
* No more things to do, just break.
*
* 4) (last_vma_end - 1) is the middle of a vma (VMA'):
*
- * find_vma(mm, 16k - 1) will return VMA' whose range
+ * vma_next(vmi) will return VMA' whose range
* contains last_vma_end.
* Iterate VMA' from last_vma_end.
*/
- vma = mas_find(&mas, ULONG_MAX);
+ vma = vma_next(&vmi);
/* Case 3 above */
if (!vma)
break;
- /* Case 1 above */
+ /* Case 1 and 2 above */
if (vma->vm_start >= last_vma_end)
continue;
@@ -982,8 +982,7 @@ static int show_smaps_rollup(struct seq_
if (vma->vm_end > last_vma_end)
smap_gather_stats(vma, &mss, last_vma_end);
}
- /* Case 2 above */
- } while ((vma = mas_find(&mas, ULONG_MAX)) != NULL);
+ } for_each_vma(vmi, vma);
empty_set:
show_vma_header_prefix(m, vma_start, last_vma_end, 0, 0, 0, 0);
@@ -1279,7 +1278,7 @@ static ssize_t clear_refs_write(struct f
return -ESRCH;
mm = get_task_mm(task);
if (mm) {
- MA_STATE(mas, &mm->mm_mt, 0, 0);
+ VMA_ITERATOR(vmi, mm, 0);
struct mmu_notifier_range range;
struct clear_refs_private cp = {
.type = type,
@@ -1299,7 +1298,7 @@ static ssize_t clear_refs_write(struct f
}
if (type == CLEAR_REFS_SOFT_DIRTY) {
- mas_for_each(&mas, vma, ULONG_MAX) {
+ for_each_vma(vmi, vma) {
if (!(vma->vm_flags & VM_SOFTDIRTY))
continue;
vma->vm_flags &= ~VM_SOFTDIRTY;
_
Patches currently in -mm which might be from Liam.Howlett@xxxxxxxxxx are
maple_tree-add-mas_init-function.patch
maple_tree-fix-potential-rcu-issue.patch
maple_tree-reduce-user-error-potential.patch
test_maple_tree-test-modifications-while-iterating.patch
mm-expand-vma-iterator-interface.patch
mm-mmap-convert-brk-to-use-vma-iterator.patch
kernel-fork-convert-forking-to-using-the-vmi-iterator.patch
mmap-convert-vma_link-vma-iterator.patch
mm-mmap-remove-preallocation-from-do_mas_align_munmap.patch
mmap-change-do_mas_munmap-and-do_mas_aligned_munmap-to-use-vma-iterator.patch
mmap-convert-vma_expand-to-use-vma-iterator.patch
mm-add-temporary-vma-iterator-versions-of-vma_merge-split_vma-and-__split_vma.patch
ipc-shm-use-the-vma-iterator-for-munmap-calls.patch
userfaultfd-use-vma-iterator.patch
mm-change-mprotect_fixup-to-vma-iterator.patch
mlock-convert-mlock-to-vma-iterator.patch
coredump-convert-to-vma-iterator.patch
mempolicy-convert-to-vma-iterator.patch
task_mmu-convert-to-vma-iterator.patch
sched-convert-to-vma-iterator.patch
madvise-use-vmi-iterator-for-__split_vma-and-vma_merge.patch
mmap-pass-through-vmi-iterator-to-__split_vma.patch
mmap-use-vmi-version-of-vma_merge.patch
mm-mremap-use-vmi-version-of-vma_merge.patch
nommu-convert-nommu-to-using-the-vma-iterator.patch
mm-switch-vma_merge-split_vma-and-__split_vma-to-vma-iterator.patch
mmap-convert-__vma_adjust-to-use-vma-iterator.patch
mm-pass-through-vma-iterator-to-__vma_adjust.patch
madvise-use-split_vma-instead-of-__split_vma.patch
mm-remove-unnecessary-write-to-vma-iterator-in-__vma_adjust.patch
mm-pass-vma-iterator-through-to-__vma_adjust.patch
mm-add-vma-iterator-to-vma_adjust-arguments.patch
mmap-clean-up-mmap_region-unrolling.patch
mm-change-munmap-splitting-order-and-move_vma.patch
mm-mmap-move-anon_vma-setting-in-__vma_adjust.patch
mm-mmap-refactor-locking-out-of-__vma_adjust.patch
mm-mmap-use-vma_prepare-and-vma_complete-in-vma_expand.patch
mm-mmap-introduce-init_vma_prep-and-init_multi_vma_prep.patch
mm-dont-use-__vma_adjust-in-__split_vma.patch
mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages.patch
mm-mmap-introduce-dup_vma_anon-helper.patch
mm-mmap-convert-do_brk_flags-to-use-vma_prepare-and-vma_complete.patch
mm-mmap-remove-__vma_adjust.patch
vma_merge-set-vma-iterator-to-correct-position.patch
