Commit c4c84f06 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

fs/proc/task_mmu: stop using linked list and highest_vm_end 

Remove references to mm_struct linked list and highest_vm_end for when
they are removed

Link: https://lkml.kernel.org/r/20220906194824.2110408-44-Liam.Howlett@oracle.com


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarLiam R. Howlett <Liam.Howlett@Oracle.com>
Tested-by: default avatarYu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: SeongJae Park <sj@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 5f14b924

fs/proc/internal.h

+1 −1
Original line number Diff line number Diff line
@@ -285,7 +285,7 @@ struct proc_maps_private { 
	struct task_struct *task;

	struct mm_struct *mm;

#ifdef CONFIG_MMU

	struct vm_area_struct *tail_vma;

	struct vma_iterator iter;

#endif

#ifdef CONFIG_NUMA

	struct mempolicy *task_mempolicy;

fs/proc/task_mmu.c

+41 −32
Original line number Diff line number Diff line
@@ -123,12 +123,26 @@ static void release_task_mempolicy(struct proc_maps_private *priv) 
}

#endif



static struct vm_area_struct *proc_get_vma(struct proc_maps_private *priv,

						loff_t *ppos)

{

	struct vm_area_struct *vma = vma_next(&priv->iter);



	if (vma) {

		*ppos = vma->vm_start;

	} else {

		*ppos = -2UL;

		vma = get_gate_vma(priv->mm);

	}



	return vma;

}



static void *m_start(struct seq_file *m, loff_t *ppos)

{

	struct proc_maps_private *priv = m->private;

	unsigned long last_addr = *ppos;

	struct mm_struct *mm;

	struct vm_area_struct *vma;



	/* See m_next(). Zero at the start or after lseek. */

	if (last_addr == -1UL)
@@ -152,31 +166,21 @@ static void *m_start(struct seq_file *m, loff_t *ppos) 
		return ERR_PTR(-EINTR);

	}



	vma_iter_init(&priv->iter, mm, last_addr);

	hold_task_mempolicy(priv);

	priv->tail_vma = get_gate_vma(mm);



	vma = find_vma(mm, last_addr);

	if (vma)

		return vma;

	if (last_addr == -2UL)

		return get_gate_vma(mm);



	return priv->tail_vma;

	return proc_get_vma(priv, ppos);

}



static void *m_next(struct seq_file *m, void *v, loff_t *ppos)

{

	struct proc_maps_private *priv = m->private;

	struct vm_area_struct *next, *vma = v;



	if (vma == priv->tail_vma)

		next = NULL;

	else if (vma->vm_next)

		next = vma->vm_next;

	else

		next = priv->tail_vma;



	*ppos = next ? next->vm_start : -1UL;



	return next;

	if (*ppos == -2UL) {

		*ppos = -1UL;

		return NULL;

	}

	return proc_get_vma(m->private, ppos);

}



static void m_stop(struct seq_file *m, void *v)
@@ -876,16 +880,16 @@ static int show_smaps_rollup(struct seq_file *m, void *v) 
{

	struct proc_maps_private *priv = m->private;

	struct mem_size_stats mss;

	struct mm_struct *mm;

	struct mm_struct *mm = priv->mm;

	struct vm_area_struct *vma;

	unsigned long last_vma_end = 0;

	unsigned long vma_start = 0, last_vma_end = 0;

	int ret = 0;

	MA_STATE(mas, &mm->mm_mt, 0, 0);



	priv->task = get_proc_task(priv->inode);

	if (!priv->task)

		return -ESRCH;



	mm = priv->mm;

	if (!mm || !mmget_not_zero(mm)) {

		ret = -ESRCH;

		goto out_put_task;
@@ -898,8 +902,13 @@ static int show_smaps_rollup(struct seq_file *m, void *v) 
		goto out_put_mm;



	hold_task_mempolicy(priv);

	vma = mas_find(&mas, 0);



	for (vma = priv->mm->mmap; vma;) {

	if (unlikely(!vma))

		goto empty_set;



	vma_start = vma->vm_start;

	do {

		smap_gather_stats(vma, &mss, 0);

		last_vma_end = vma->vm_end;
@@ -908,6 +917,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v) 
		 * access it for write request.

		 */

		if (mmap_lock_is_contended(mm)) {

			mas_pause(&mas);

			mmap_read_unlock(mm);

			ret = mmap_read_lock_killable(mm);

			if (ret) {
@@ -951,7 +961,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v) 
			 *    contains last_vma_end.

			 *    Iterate VMA' from last_vma_end.

			 */

			vma = find_vma(mm, last_vma_end - 1);

			vma = mas_find(&mas, ULONG_MAX);

			/* Case 3 above */

			if (!vma)

				break;
@@ -965,11 +975,10 @@ static int show_smaps_rollup(struct seq_file *m, void *v) 
				smap_gather_stats(vma, &mss, last_vma_end);

		}

		/* Case 2 above */

		vma = vma->vm_next;

	}

	} while ((vma = mas_find(&mas, ULONG_MAX)) != NULL);



	show_vma_header_prefix(m, priv->mm->mmap->vm_start,

			       last_vma_end, 0, 0, 0, 0);

empty_set:

	show_vma_header_prefix(m, vma_start, last_vma_end, 0, 0, 0, 0);

	seq_pad(m, ' ');

	seq_puts(m, "[rollup]\n");
@@ -1262,6 +1271,7 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, 
		return -ESRCH;

	mm = get_task_mm(task);

	if (mm) {

		MA_STATE(mas, &mm->mm_mt, 0, 0);

		struct mmu_notifier_range range;

		struct clear_refs_private cp = {

			.type = type,
@@ -1281,7 +1291,7 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, 
		}



		if (type == CLEAR_REFS_SOFT_DIRTY) {

			for (vma = mm->mmap; vma; vma = vma->vm_next) {

			mas_for_each(&mas, vma, ULONG_MAX) {

				if (!(vma->vm_flags & VM_SOFTDIRTY))

					continue;

				vma->vm_flags &= ~VM_SOFTDIRTY;
@@ -1293,8 +1303,7 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, 
						0, NULL, mm, 0, -1UL);

			mmu_notifier_invalidate_range_start(&range);

		}

		walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops,

				&cp);

		walk_page_range(mm, 0, -1, &clear_refs_walk_ops, &cp);

		if (type == CLEAR_REFS_SOFT_DIRTY) {

			mmu_notifier_invalidate_range_end(&range);

			flush_tlb_mm(mm);