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: move MIN_WRITEBACK_PAGES to fs-writeback.c
  writeback: balanced_rate cannot exceed write bandwidth
  writeback: do strict bdi dirty_exceeded
  writeback: avoid tiny dirty poll intervals
  writeback: max, min and target dirty pause time
  writeback: dirty ratelimit - think time compensation
  btrfs: fix dirtied pages accounting on sub-page writes
  writeback: fix dirtied pages accounting on redirty
  writeback: fix dirtied pages accounting on sub-page writes
  writeback: charge leaked page dirties to active tasks
  writeback: Include all dirty inodes in background writeback

3 files changed, 16 insertions, 8 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index f044f66018f2..21cd0303af51 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1544,6 +1544,7 @@ struct task_struct {
          */
         int nr_dirtied;
         int nr_dirtied_pause;
+        unsigned long dirty_paused_when; /* start of a write-and-pause period */
 
 #ifdef CONFIG_LATENCYTOP
         int latency_record_count;
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 6dff47304971..995b8bf630ac 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -7,6 +7,8 @@
 #include <linux/sched.h>
 #include <linux/fs.h>
 
+DECLARE_PER_CPU(int, dirty_throttle_leaks);
+
 /*
  * The 1/4 region under the global dirty thresh is for smooth dirty throttling:
  *
@@ -23,11 +25,6 @@
 #define DIRTY_SCOPE             8
 #define DIRTY_FULL_SCOPE        (DIRTY_SCOPE / 2)
 
-/*
- * 4MB minimal write chunk size
- */
-#define MIN_WRITEBACK_PAGES     (4096UL >> (PAGE_CACHE_SHIFT - 10))
-
 struct backing_dev_info;
 
 /*
@@ -194,6 +191,8 @@ void writeback_set_ratelimit(void);
 void tag_pages_for_writeback(struct address_space *mapping,
                              pgoff_t start, pgoff_t end);
 
+void account_page_redirty(struct page *page);
+
 /* pdflush.c */
 extern int nr_pdflush_threads;  /* Global so it can be exported to sysctl
                                    read-only. */
diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index 99d1d0decf88..8588a8918023 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -300,12 +300,13 @@ TRACE_EVENT(balance_dirty_pages,
                  unsigned long dirty_ratelimit,
                  unsigned long task_ratelimit,
                  unsigned long dirtied,
+                 unsigned long period,
                  long pause,
                  unsigned long start_time),
 
         TP_ARGS(bdi, thresh, bg_thresh, dirty, bdi_thresh, bdi_dirty,
                 dirty_ratelimit, task_ratelimit,
-                dirtied, pause, start_time),
+                dirtied, period, pause, start_time),
 
         TP_STRUCT__entry(
                 __array(         char,  bdi, 32)
@@ -320,6 +321,8 @@ TRACE_EVENT(balance_dirty_pages,
                 __field(unsigned int,   dirtied_pause)
                 __field(unsigned long,  paused)
                 __field(         long,  pause)
+                __field(unsigned long,  period)
+                __field(         long,  think)
         ),
 
         TP_fast_assign(
@@ -336,6 +339,9 @@ TRACE_EVENT(balance_dirty_pages,
                 __entry->task_ratelimit = KBps(task_ratelimit);
                 __entry->dirtied        = dirtied;
                 __entry->dirtied_pause  = current->nr_dirtied_pause;
+                __entry->think          = current->dirty_paused_when == 0 ? 0 :
+                         (long)(jiffies - current->dirty_paused_when) * 1000/HZ;
+                __entry->period         = period * 1000 / HZ;
                 __entry->pause          = pause * 1000 / HZ;
                 __entry->paused         = (jiffies - start_time) * 1000 / HZ;
         ),
@@ -346,7 +352,7 @@ TRACE_EVENT(balance_dirty_pages,
                   "bdi_setpoint=%lu bdi_dirty=%lu "
                   "dirty_ratelimit=%lu task_ratelimit=%lu "
                   "dirtied=%u dirtied_pause=%u "
-                  "paused=%lu pause=%ld",
+                  "paused=%lu pause=%ld period=%lu think=%ld",
                   __entry->bdi,
                   __entry->limit,
                   __entry->setpoint,
@@ -358,7 +364,9 @@ TRACE_EVENT(balance_dirty_pages,
                   __entry->dirtied,
                   __entry->dirtied_pause,
                   __entry->paused,      /* ms */
-                  __entry->pause        /* ms */
+                  __entry->pause,       /* ms */
+                  __entry->period,      /* ms */
+                  __entry->think        /* ms */
           )
 );