3 files changed, 32 insertions, 21 deletions

diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
index e8e632a1dcdf..bc5857199ec2 100644
--- a/fs/ubifs/io.c
+++ b/fs/ubifs/io.c
@@ -293,13 +293,14 @@ void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last)
  *
  * This function is called when the write-buffer timer expires.
  */
-static void wbuf_timer_callback_nolock(unsigned long data)
+static enum hrtimer_restart wbuf_timer_callback_nolock(struct hrtimer *timer)
 {
-        struct ubifs_wbuf *wbuf = (struct ubifs_wbuf *)data;
+        struct ubifs_wbuf *wbuf = container_of(timer, struct ubifs_wbuf, timer);
 
         wbuf->need_sync = 1;
         wbuf->c->need_wbuf_sync = 1;
         ubifs_wake_up_bgt(wbuf->c);
+        return HRTIMER_NORESTART;
 }
 
 /**
@@ -308,13 +309,12 @@ static void wbuf_timer_callback_nolock(unsigned long data)
  */
 static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
 {
-        ubifs_assert(!timer_pending(&wbuf->timer));
+        ubifs_assert(!hrtimer_active(&wbuf->timer));
 
-        if (!wbuf->timeout)
+        if (!ktime_to_ns(wbuf->softlimit))
                 return;
-
-        wbuf->timer.expires = jiffies + wbuf->timeout;
-        add_timer(&wbuf->timer);
+        hrtimer_start_range_ns(&wbuf->timer, wbuf->softlimit, wbuf->delta,
+                               HRTIMER_MODE_REL);
 }
 
 /**
@@ -329,7 +329,7 @@ static void cancel_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
          * should be canceled.
          */
         wbuf->need_sync = 0;
-        del_timer(&wbuf->timer);
+        hrtimer_cancel(&wbuf->timer);
 }
 
 /**
@@ -825,6 +825,7 @@ out:
 int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf)
 {
         size_t size;
+        ktime_t hardlimit;
 
         wbuf->buf = kmalloc(c->min_io_size, GFP_KERNEL);
         if (!wbuf->buf)
@@ -845,14 +846,21 @@ int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf)
         wbuf->sync_callback = NULL;
         mutex_init(&wbuf->io_mutex);
         spin_lock_init(&wbuf->lock);
-
         wbuf->c = c;
-        init_timer(&wbuf->timer);
-        wbuf->timer.function = wbuf_timer_callback_nolock;
-        wbuf->timer.data = (unsigned long)wbuf;
-        wbuf->timeout = DEFAULT_WBUF_TIMEOUT;
         wbuf->next_ino = 0;
 
+        hrtimer_init(&wbuf->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+        wbuf->timer.function = wbuf_timer_callback_nolock;
+        /*
+         * Make write-buffer soft limit to be 20% of the hard limit. The
+         * write-buffer timer is allowed to expire any time between the soft
+         * and hard limits.
+         */
+        hardlimit = ktime_set(DEFAULT_WBUF_TIMEOUT_SECS, 0);
+        wbuf->delta = (DEFAULT_WBUF_TIMEOUT_SECS * NSEC_PER_SEC) * 2 / 10;
+        wbuf->softlimit = ktime_sub_ns(hardlimit, wbuf->delta);
+        hrtimer_set_expires_range_ns(&wbuf->timer,  wbuf->softlimit,
+                                     wbuf->delta);
         return 0;
 }
 
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index b9b051a4c01e..91c91cb7a599 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -799,7 +799,7 @@ static int alloc_wbufs(struct ubifs_info *c)
          * does not need to be synchronized by timer.
          */
         c->jheads[GCHD].wbuf.dtype = UBI_LONGTERM;
-        c->jheads[GCHD].wbuf.timeout = 0;
+        c->jheads[GCHD].wbuf.softlimit = ktime_set(0, 0);
 
         return 0;
 }
@@ -1695,7 +1695,7 @@ static void ubifs_remount_ro(struct ubifs_info *c)
 
         for (i = 0; i < c->jhead_cnt; i++) {
                 ubifs_wbuf_sync(&c->jheads[i].wbuf);
-                del_timer_sync(&c->jheads[i].wbuf.timer);
+                hrtimer_cancel(&c->jheads[i].wbuf.timer);
         }
 
         c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
@@ -1755,7 +1755,7 @@ static void ubifs_put_super(struct super_block *sb)
                 if (c->jheads)
                         for (i = 0; i < c->jhead_cnt; i++) {
                                 ubifs_wbuf_sync(&c->jheads[i].wbuf);
-                                del_timer_sync(&c->jheads[i].wbuf.timer);
+                                hrtimer_cancel(&c->jheads[i].wbuf.timer);
                         }
 
                 /*
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 0a8341e14088..1bf01d820066 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -95,8 +95,8 @@
  */
 #define BGT_NAME_PATTERN "ubifs_bgt%d_%d"
 
-/* Default write-buffer synchronization timeout (5 secs) */
-#define DEFAULT_WBUF_TIMEOUT (5 * HZ)
+/* Default write-buffer synchronization timeout in seconds */
+#define DEFAULT_WBUF_TIMEOUT_SECS 5
 
 /* Maximum possible inode number (only 32-bit inodes are supported now) */
 #define MAX_INUM 0xFFFFFFFF
@@ -650,8 +650,10 @@ typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c,
  * @io_mutex: serializes write-buffer I/O
  * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes
  *        fields
+ * @softlimit: soft write-buffer timeout interval
+ * @delta: hard and soft timeouts delta (the timer expire inteval is @softlimit
+ *         and @softlimit + @delta)
  * @timer: write-buffer timer
- * @timeout: timer expire interval in jiffies
  * @need_sync: it is set if its timer expired and needs sync
  * @next_ino: points to the next position of the following inode number
  * @inodes: stores the inode numbers of the nodes which are in wbuf
@@ -678,8 +680,9 @@ struct ubifs_wbuf {
         int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad);
         struct mutex io_mutex;
         spinlock_t lock;
-        struct timer_list timer;
-        int timeout;
+        ktime_t softlimit;
+        unsigned long long delta;
+        struct hrtimer timer;
         int need_sync;
         int next_ino;
         ino_t *inodes;