Merge branch 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux

* 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: remove vm_dirties and task->dirties
  writeback: hard throttle 1000+ dd on a slow USB stick
  mm: Make task in balance_dirty_pages() killable

4 files changed, 7 insertions, 23 deletions

diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 08ffab01e76c..94b1e356c02a 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -184,7 +184,6 @@ extern struct cred init_cred;
                 [PIDTYPE_SID]  = INIT_PID_LINK(PIDTYPE_SID),            \
         },                                                              \
         .thread_group   = LIST_HEAD_INIT(tsk.thread_group),             \
-        .dirties = INIT_PROP_LOCAL_SINGLE(dirties),                     \
         INIT_IDS                                                        \
         INIT_PERF_EVENTS(tsk)                                           \
         INIT_TRACE_IRQFLAGS                                             \
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 68daf4f27e2c..1c4f3e9b9bc5 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1521,7 +1521,6 @@ struct task_struct {
 #ifdef CONFIG_FAULT_INJECTION
         int make_it_fail;
 #endif
-        struct prop_local_single dirties;
         /*
          * when (nr_dirtied >= nr_dirtied_pause), it's time to call
          * balance_dirty_pages() for some dirty throttling pause
diff --git a/kernel/fork.c b/kernel/fork.c
index ba0d17261329..da4a6a10d088 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -162,7 +162,6 @@ static void account_kernel_stack(struct thread_info *ti, int account)
 
 void free_task(struct task_struct *tsk)
 {
-        prop_local_destroy_single(&tsk->dirties);
         account_kernel_stack(tsk->stack, -1);
         free_thread_info(tsk->stack);
         rt_mutex_debug_task_free(tsk);
@@ -274,10 +273,6 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
 
         tsk->stack = ti;
 
-        err = prop_local_init_single(&tsk->dirties);
-        if (err)
-                goto out;
-
         setup_thread_stack(tsk, orig);
         clear_user_return_notifier(tsk);
         clear_tsk_need_resched(tsk);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index a3278f005230..71252486bc6f 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -128,7 +128,6 @@ unsigned long global_dirty_limit;
  *
  */
 static struct prop_descriptor vm_completions;
-static struct prop_descriptor vm_dirties;
 
 /*
  * couple the period to the dirty_ratio:
@@ -154,7 +153,6 @@ static void update_completion_period(void)
 {
         int shift = calc_period_shift();
         prop_change_shift(&vm_completions, shift);
-        prop_change_shift(&vm_dirties, shift);
 
         writeback_set_ratelimit();
 }
@@ -235,11 +233,6 @@ void bdi_writeout_inc(struct backing_dev_info *bdi)
 }
 EXPORT_SYMBOL_GPL(bdi_writeout_inc);
 
-void task_dirty_inc(struct task_struct *tsk)
-{
-        prop_inc_single(&vm_dirties, &tsk->dirties);
-}
-
 /*
  * Obtain an accurate fraction of the BDI's portion.
  */
@@ -1133,17 +1126,17 @@ pause:
                                           pages_dirtied,
                                           pause,
                                           start_time);
-                __set_current_state(TASK_UNINTERRUPTIBLE);
+                __set_current_state(TASK_KILLABLE);
                 io_schedule_timeout(pause);
 
-                dirty_thresh = hard_dirty_limit(dirty_thresh);
                 /*
-                 * max-pause area. If dirty exceeded but still within this
-                 * area, no need to sleep for more than 200ms: (a) 8 pages per
-                 * 200ms is typically more than enough to curb heavy dirtiers;
-                 * (b) the pause time limit makes the dirtiers more responsive.
+                 * This is typically equal to (nr_dirty < dirty_thresh) and can
+                 * also keep "1000+ dd on a slow USB stick" under control.
                  */
-                if (nr_dirty < dirty_thresh)
+                if (task_ratelimit)
+                        break;
+
+                if (fatal_signal_pending(current))
                         break;
         }
 
@@ -1395,7 +1388,6 @@ void __init page_writeback_init(void)
 
         shift = calc_period_shift();
         prop_descriptor_init(&vm_completions, shift);
-        prop_descriptor_init(&vm_dirties, shift);
 }
 
 /**
@@ -1724,7 +1716,6 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)
                 __inc_zone_page_state(page, NR_DIRTIED);
                 __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
                 __inc_bdi_stat(mapping->backing_dev_info, BDI_DIRTIED);
-                task_dirty_inc(current);
                 task_io_account_write(PAGE_CACHE_SIZE);
         }
 }