fs-writeback: Add helper function to start writeback if idle

[safe/jmp/linux-2.6] / fs / proc / array.c

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 762aea9..f560325 100644 (file)
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -82,6 +82,7 @@
 #include <linux/pid_namespace.h>
 #include <linux/ptrace.h>
 #include <linux/tracehook.h>
+#include <linux/swapops.h>
 
 #include <asm/pgtable.h>
 #include <asm/processor.h>
@@ -133,13 +134,16 @@ static inline void task_name(struct seq_file *m, struct task_struct *p)
  * simple bit tests.
  */
 static const char *task_state_array[] = {
-       "R (running)",          /*  0 */
-       "S (sleeping)",         /*  1 */
-       "D (disk sleep)",       /*  2 */
-       "T (stopped)",          /*  4 */
-       "T (tracing stop)",     /*  8 */
-       "Z (zombie)",           /* 16 */
-       "X (dead)"              /* 32 */
+       "R (running)",          /*   0 */
+       "S (sleeping)",         /*   1 */
+       "D (disk sleep)",       /*   2 */
+       "T (stopped)",          /*   4 */
+       "t (tracing stop)",     /*   8 */
+       "Z (zombie)",           /*  16 */
+       "X (dead)",             /*  32 */
+       "x (dead)",             /*  64 */
+       "K (wakekill)",         /* 128 */
+       "W (waking)",           /* 256 */
 };
 
 static inline const char *get_task_state(struct task_struct *tsk)
@@ -147,6 +151,8 @@ static inline const char *get_task_state(struct task_struct *tsk)
        unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
        const char **p = &task_state_array[0];
 
+       BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array));
+
        while (state) {
                p++;
                state >>= 1;
@@ -321,6 +327,94 @@ static inline void task_context_switch_counts(struct seq_file *m,
                        p->nivcsw);
 }
 
+#ifdef CONFIG_MMU
+
+struct stack_stats {
+       struct vm_area_struct *vma;
+       unsigned long   startpage;
+       unsigned long   usage;
+};
+
+static int stack_usage_pte_range(pmd_t *pmd, unsigned long addr,
+                               unsigned long end, struct mm_walk *walk)
+{
+       struct stack_stats *ss = walk->private;
+       struct vm_area_struct *vma = ss->vma;
+       pte_t *pte, ptent;
+       spinlock_t *ptl;
+       int ret = 0;
+
+       pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+       for (; addr != end; pte++, addr += PAGE_SIZE) {
+               ptent = *pte;
+
+#ifdef CONFIG_STACK_GROWSUP
+               if (pte_present(ptent) || is_swap_pte(ptent))
+                       ss->usage = addr - ss->startpage + PAGE_SIZE;
+#else
+               if (pte_present(ptent) || is_swap_pte(ptent)) {
+                       ss->usage = ss->startpage - addr + PAGE_SIZE;
+                       pte++;
+                       ret = 1;
+                       break;
+               }
+#endif
+       }
+       pte_unmap_unlock(pte - 1, ptl);
+       cond_resched();
+       return ret;
+}
+
+static inline unsigned long get_stack_usage_in_bytes(struct vm_area_struct *vma,
+                               struct task_struct *task)
+{
+       struct stack_stats ss;
+       struct mm_walk stack_walk = {
+               .pmd_entry = stack_usage_pte_range,
+               .mm = vma->vm_mm,
+               .private = &ss,
+       };
+
+       if (!vma->vm_mm || is_vm_hugetlb_page(vma))
+               return 0;
+
+       ss.vma = vma;
+       ss.startpage = task->stack_start & PAGE_MASK;
+       ss.usage = 0;
+
+#ifdef CONFIG_STACK_GROWSUP
+       walk_page_range(KSTK_ESP(task) & PAGE_MASK, vma->vm_end,
+               &stack_walk);
+#else
+       walk_page_range(vma->vm_start, (KSTK_ESP(task) & PAGE_MASK) + PAGE_SIZE,
+               &stack_walk);
+#endif
+       return ss.usage;
+}
+
+static inline void task_show_stack_usage(struct seq_file *m,
+                                               struct task_struct *task)
+{
+       struct vm_area_struct   *vma;
+       struct mm_struct        *mm = get_task_mm(task);
+
+       if (mm) {
+               down_read(&mm->mmap_sem);
+               vma = find_vma(mm, task->stack_start);
+               if (vma)
+                       seq_printf(m, "Stack usage:\t%lu kB\n",
+                               get_stack_usage_in_bytes(vma, task) >> 10);
+
+               up_read(&mm->mmap_sem);
+               mmput(mm);
+       }
+}
+#else
+static void task_show_stack_usage(struct seq_file *m, struct task_struct *task)
+{
+}
+#endif         /* CONFIG_MMU */
+
 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
 {
        seq_printf(m, "Cpus_allowed:\t");
@@ -351,6 +445,7 @@ int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
        task_show_regs(m, task);
 #endif
        task_context_switch_counts(m, task);
+       task_show_stack_usage(m, task);
        return 0;
 }
 
@@ -416,20 +511,17 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
 
                /* add up live thread stats at the group level */
                if (whole) {
-                       struct task_cputime cputime;
                        struct task_struct *t = task;
                        do {
                                min_flt += t->min_flt;
                                maj_flt += t->maj_flt;
-                               gtime = cputime_add(gtime, task_gtime(t));
+                               gtime = cputime_add(gtime, t->gtime);
                                t = next_thread(t);
                        } while (t != task);
 
                        min_flt += sig->min_flt;
                        maj_flt += sig->maj_flt;
-                       thread_group_cputime(task, &cputime);
-                       utime = cputime.utime;
-                       stime = cputime.stime;
+                       thread_group_times(task, &utime, &stime);
                        gtime = cputime_add(gtime, sig->gtime);
                }
 
@@ -445,9 +537,8 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
        if (!whole) {
                min_flt = task->min_flt;
                maj_flt = task->maj_flt;
-               utime = task_utime(task);
-               stime = task_stime(task);
-               gtime = task_gtime(task);
+               task_times(task, &utime, &stime);
+               gtime = task->gtime;
        }
 
        /* scale priority and nice values from timeslices to -20..20 */
@@ -492,7 +583,7 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
                rsslim,
                mm ? mm->start_code : 0,
                mm ? mm->end_code : 0,
-               (permitted && mm) ? mm->start_stack : 0,
+               (permitted && mm) ? task->stack_start : 0,
                esp,
                eip,
                /* The signal information here is obsolete.