2 files changed, 37 insertions, 27 deletions

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index b41823cc05e6..d3ca2b3ee176 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -158,16 +158,16 @@ static ssize_t read_ahead_kb_store(struct device *dev,
                                   const char *buf, size_t count)
 {
         struct backing_dev_info *bdi = dev_get_drvdata(dev);
-        char *end;
         unsigned long read_ahead_kb;
-        ssize_t ret = -EINVAL;
+        ssize_t ret;
 
-        read_ahead_kb = simple_strtoul(buf, &end, 10);
-        if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) {
-                bdi->ra_pages = read_ahead_kb >> (PAGE_SHIFT - 10);
-                ret = count;
-        }
-        return ret;
+        ret = kstrtoul(buf, 10, &read_ahead_kb);
+        if (ret < 0)
+                return ret;
+
+        bdi->ra_pages = read_ahead_kb >> (PAGE_SHIFT - 10);
+
+        return count;
 }
 
 #define K(pages) ((pages) << (PAGE_SHIFT - 10))
@@ -187,16 +187,17 @@ static ssize_t min_ratio_store(struct device *dev,
                 struct device_attribute *attr, const char *buf, size_t count)
 {
         struct backing_dev_info *bdi = dev_get_drvdata(dev);
-        char *end;
         unsigned int ratio;
-        ssize_t ret = -EINVAL;
+        ssize_t ret;
+
+        ret = kstrtouint(buf, 10, &ratio);
+        if (ret < 0)
+                return ret;
+
+        ret = bdi_set_min_ratio(bdi, ratio);
+        if (!ret)
+                ret = count;
 
-        ratio = simple_strtoul(buf, &end, 10);
-        if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) {
-                ret = bdi_set_min_ratio(bdi, ratio);
-                if (!ret)
-                        ret = count;
-        }
         return ret;
 }
 BDI_SHOW(min_ratio, bdi->min_ratio)
@@ -205,16 +206,17 @@ static ssize_t max_ratio_store(struct device *dev,
                 struct device_attribute *attr, const char *buf, size_t count)
 {
         struct backing_dev_info *bdi = dev_get_drvdata(dev);
-        char *end;
         unsigned int ratio;
-        ssize_t ret = -EINVAL;
+        ssize_t ret;
+
+        ret = kstrtouint(buf, 10, &ratio);
+        if (ret < 0)
+                return ret;
+
+        ret = bdi_set_max_ratio(bdi, ratio);
+        if (!ret)
+                ret = count;
 
-        ratio = simple_strtoul(buf, &end, 10);
-        if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) {
-                ret = bdi_set_max_ratio(bdi, ratio);
-                if (!ret)
-                        ret = count;
-        }
         return ret;
 }
 BDI_SHOW(max_ratio, bdi->max_ratio)
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 5ad5ce23c1e0..830893b2b3c7 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1602,10 +1602,18 @@ void writeback_set_ratelimit(void)
 }
 
 static int __cpuinit
-ratelimit_handler(struct notifier_block *self, unsigned long u, void *v)
+ratelimit_handler(struct notifier_block *self, unsigned long action,
+                  void *hcpu)
 {
-        writeback_set_ratelimit();
-        return NOTIFY_DONE;
+
+        switch (action & ~CPU_TASKS_FROZEN) {
+        case CPU_ONLINE:
+        case CPU_DEAD:
+                writeback_set_ratelimit();
+                return NOTIFY_OK;
+        default:
+                return NOTIFY_DONE;
+        }
 }
 
 static struct notifier_block __cpuinitdata ratelimit_nb = {