procfs: provide stack information for threads

[linux.git] / fs / proc / task_mmu.c

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 9bd8be1d235c2b420e348d25e801bdce88efd977..2a1bef9203c6e73734e7fa359873bbb45456d0ae 100644 (file)
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -243,6 +243,25 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
                                } else if (vma->vm_start <= mm->start_stack &&
                                           vma->vm_end >= mm->start_stack) {
                                        name = "[stack]";
                                } else if (vma->vm_start <= mm->start_stack &&
                                           vma->vm_end >= mm->start_stack) {
                                        name = "[stack]";

+                               } else {
+                                       unsigned long stack_start;
+                                       struct proc_maps_private *pmp;
+
+                                       pmp = m->private;
+                                       stack_start = pmp->task->stack_start;
+
+                                       if (vma->vm_start <= stack_start &&
+                                           vma->vm_end >= stack_start) {
+                                               pad_len_spaces(m, len);
+                                               seq_printf(m,
+                                                "[threadstack:%08lx]",
+#ifdef CONFIG_STACK_GROWSUP
+                                                vma->vm_end - stack_start
+#else
+                                                stack_start - vma->vm_start
+#endif
+                                               );
+                                       }

                                }
                        } else {
                                name = "[vdso]";
                                }
                        } else {
                                name = "[vdso]";


@@ -465,23 +484,28 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
        return 0;
 }
 
        return 0;
 }
 

+#define CLEAR_REFS_ALL 1
+#define CLEAR_REFS_ANON 2
+#define CLEAR_REFS_MAPPED 3
+

 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                                size_t count, loff_t *ppos)
 {
        struct task_struct *task;
 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                                size_t count, loff_t *ppos)
 {
        struct task_struct *task;

-       char buffer[PROC_NUMBUF], *end;
+       char buffer[PROC_NUMBUF];

        struct mm_struct *mm;
        struct vm_area_struct *vma;
        struct mm_struct *mm;
        struct vm_area_struct *vma;

+       long type;

 
        memset(buffer, 0, sizeof(buffer));
        if (count > sizeof(buffer) - 1)
                count = sizeof(buffer) - 1;
        if (copy_from_user(buffer, buf, count))
                return -EFAULT;
 
        memset(buffer, 0, sizeof(buffer));
        if (count > sizeof(buffer) - 1)
                count = sizeof(buffer) - 1;
        if (copy_from_user(buffer, buf, count))
                return -EFAULT;

-       if (!simple_strtol(buffer, &end, 0))
+       if (strict_strtol(strstrip(buffer), 10, &type))
+               return -EINVAL;
+       if (type < CLEAR_REFS_ALL || type > CLEAR_REFS_MAPPED)

                return -EINVAL;
                return -EINVAL;

-       if (*end == '\n')
-               end++;

        task = get_proc_task(file->f_path.dentry->d_inode);
        if (!task)
                return -ESRCH;
        task = get_proc_task(file->f_path.dentry->d_inode);
        if (!task)
                return -ESRCH;


@@ -494,18 +518,31 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                down_read(&mm->mmap_sem);
                for (vma = mm->mmap; vma; vma = vma->vm_next) {
                        clear_refs_walk.private = vma;
                down_read(&mm->mmap_sem);
                for (vma = mm->mmap; vma; vma = vma->vm_next) {
                        clear_refs_walk.private = vma;

-                       if (!is_vm_hugetlb_page(vma))
-                               walk_page_range(vma->vm_start, vma->vm_end,
-                                               &clear_refs_walk);
+                       if (is_vm_hugetlb_page(vma))
+                               continue;
+                       /*
+                        * Writing 1 to /proc/pid/clear_refs affects all pages.
+                        *
+                        * Writing 2 to /proc/pid/clear_refs only affects
+                        * Anonymous pages.
+                        *
+                        * Writing 3 to /proc/pid/clear_refs only affects file
+                        * mapped pages.
+                        */
+                       if (type == CLEAR_REFS_ANON && vma->vm_file)
+                               continue;
+                       if (type == CLEAR_REFS_MAPPED && !vma->vm_file)
+                               continue;
+                       walk_page_range(vma->vm_start, vma->vm_end,
+                                       &clear_refs_walk);

                }
                flush_tlb_mm(mm);
                up_read(&mm->mmap_sem);
                mmput(mm);
        }
        put_task_struct(task);
                }
                flush_tlb_mm(mm);
                up_read(&mm->mmap_sem);
                mmput(mm);
        }
        put_task_struct(task);

-       if (end - buffer == 0)
-               return -EIO;
-       return end - buffer;
+
+       return count;

 }
 
 const struct file_operations proc_clear_refs_operations = {
 }
 
 const struct file_operations proc_clear_refs_operations = {