From c4c84f06285e48f80e9843d0775ad92714ffc35a Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 6 Sep 2022 19:48:57 +0000 Subject: 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: Matthew Wilcox (Oracle) Signed-off-by: Liam R. Howlett Tested-by: Yu Zhao Cc: Catalin Marinas Cc: David Hildenbrand Cc: David Howells Cc: Davidlohr Bueso Cc: SeongJae Park Cc: Sven Schnelle Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton --- fs/proc/internal.h | 2 +- fs/proc/task_mmu.c | 73 ++++++++++++++++++++++++++++++------------------------ 2 files changed, 42 insertions(+), 33 deletions(-) diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 06a80f78433d..f03000764ce5 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -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; diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 9f70bc1c2766..8b4f3073f8f5 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -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); + + if (unlikely(!vma)) + goto empty_set; - for (vma = priv->mm->mmap; vma;) { + 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); -- cgit v1.2.3