From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Instead of calling vma_stop() from m_start() and m_next(), do its work in m_stop(). Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> --- fs/proc/task_mmu.c | 34 +++++++++++++++------------------- 1 file changed, 15 insertions(+), 19 deletions(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 9442631fd4af..41f63df4789d 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -123,15 +123,6 @@ static void release_task_mempolicy(struct proc_maps_private *priv) } #endif -static void vma_stop(struct proc_maps_private *priv) -{ - struct mm_struct *mm = priv->mm; - - release_task_mempolicy(priv); - up_read(&mm->mmap_sem); - mmput(mm); -} - static struct vm_area_struct * m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma) { @@ -163,11 +154,16 @@ static void *m_start(struct seq_file *m, loff_t *ppos) return ERR_PTR(-ESRCH); mm = priv->mm; - if (!mm || !mmget_not_zero(mm)) + if (!mm || !mmget_not_zero(mm)) { + put_task_struct(priv->task); + priv->task = NULL; return NULL; + } if (down_read_killable(&mm->mmap_sem)) { mmput(mm); + put_task_struct(priv->task); + priv->task = NULL; return ERR_PTR(-EINTR); } @@ -195,7 +191,6 @@ static void *m_start(struct seq_file *m, loff_t *ppos) if (pos == mm->map_count && priv->tail_vma) return priv->tail_vma; - vma_stop(priv); return NULL; } @@ -206,21 +201,22 @@ static void *m_next(struct seq_file *m, void *v, loff_t *pos) (*pos)++; next = m_next_vma(priv, v); - if (!next) - vma_stop(priv); return next; } static void m_stop(struct seq_file *m, void *v) { struct proc_maps_private *priv = m->private; + struct mm_struct *mm = priv->mm; - if (!IS_ERR_OR_NULL(v)) - vma_stop(priv); - if (priv->task) { - put_task_struct(priv->task); - priv->task = NULL; - } + if (!priv->task) + return; + + release_task_mempolicy(priv); + up_read(&mm->mmap_sem); + mmput(mm); + put_task_struct(priv->task); + priv->task = NULL; } static int proc_maps_open(struct inode *inode, struct file *file, -- 2.25.0