6 files changed, 39 insertions, 17 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 1fafb4b99c9b..ff017108700d 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -356,7 +356,7 @@ config SLUB_STATS
 config DEBUG_KMEMLEAK
         bool "Kernel memory leak detector"
         depends on DEBUG_KERNEL && EXPERIMENTAL && !MEMORY_HOTPLUG && \
-                (X86 || ARM || PPC || S390 || SUPERH)
+                (X86 || ARM || PPC || S390 || SUPERH || MICROBLAZE)
 
         select DEBUG_FS if SYSFS
         select STACKTRACE if STACKTRACE_SUPPORT
diff --git a/lib/Makefile b/lib/Makefile
index 2e152aed7198..0d4015205c64 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -21,7 +21,7 @@ lib-y	+= kobject.o kref.o klist.o
 
 obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
          bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
-         string_helpers.o gcd.o list_sort.o
+         string_helpers.o gcd.o lcm.o list_sort.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
diff --git a/lib/lcm.c b/lib/lcm.c
new file mode 100644
index 000000000000..157cd88a6ffc
--- /dev/null
+++ b/lib/lcm.c
@@ -0,0 +1,15 @@
+#include <linux/kernel.h>
+#include <linux/gcd.h>
+#include <linux/module.h>
+
+/* Lowest common multiple */
+unsigned long lcm(unsigned long a, unsigned long b)
+{
+        if (a && b)
+                return (a * b) / gcd(a, b);
+        else if (b)
+                return b;
+
+        return a;
+}
+EXPORT_SYMBOL_GPL(lcm);
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 0871582aa29d..2a087e0f9863 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -555,6 +555,10 @@ EXPORT_SYMBOL(radix_tree_tag_clear);
  *
  *  0: tag not present or not set
  *  1: tag set
+ *
+ * Note that the return value of this function may not be relied on, even if
+ * the RCU lock is held, unless tag modification and node deletion are excluded
+ * from concurrency.
  */
 int radix_tree_tag_get(struct radix_tree_root *root,
                         unsigned long index, unsigned int tag)
@@ -595,12 +599,8 @@ int radix_tree_tag_get(struct radix_tree_root *root,
                  */
                 if (!tag_get(node, tag, offset))
                         saw_unset_tag = 1;
-                if (height == 1) {
-                        int ret = tag_get(node, tag, offset);
-
-                        BUG_ON(ret && saw_unset_tag);
-                        return !!ret;
-                }
+                if (height == 1)
+                        return !!tag_get(node, tag, offset);
                 node = rcu_dereference_raw(node->slots[offset]);
                 shift -= RADIX_TREE_MAP_SHIFT;
                 height--;
diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index 09f5ce1810dc..027a03f4c56d 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -16,9 +16,14 @@
 /*
  * __ratelimit - rate limiting
  * @rs: ratelimit_state data
+ * @func: name of calling function
  *
- * This enforces a rate limit: not more than @rs->ratelimit_burst callbacks
- * in every @rs->ratelimit_jiffies
+ * This enforces a rate limit: not more than @rs->burst callbacks
+ * in every @rs->interval
+ *
+ * RETURNS:
+ * 0 means callbacks will be suppressed.
+ * 1 means go ahead and do it.
  */
 int ___ratelimit(struct ratelimit_state *rs, const char *func)
 {
@@ -35,7 +40,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
          * the entity that is holding the lock already:
          */
         if (!spin_trylock_irqsave(&rs->lock, flags))
-                return 1;
+                return 0;
 
         if (!rs->begin)
                 rs->begin = jiffies;
diff --git a/lib/rwsem-spinlock.c b/lib/rwsem-spinlock.c
index ccf95bff7984..ffc9fc7f3b05 100644
--- a/lib/rwsem-spinlock.c
+++ b/lib/rwsem-spinlock.c
@@ -143,13 +143,14 @@ void __sched __down_read(struct rw_semaphore *sem)
 {
         struct rwsem_waiter waiter;
         struct task_struct *tsk;
+        unsigned long flags;
 
-        spin_lock_irq(&sem->wait_lock);
+        spin_lock_irqsave(&sem->wait_lock, flags);
 
         if (sem->activity >= 0 && list_empty(&sem->wait_list)) {
                 /* granted */
                 sem->activity++;
-                spin_unlock_irq(&sem->wait_lock);
+                spin_unlock_irqrestore(&sem->wait_lock, flags);
                 goto out;
         }
 
@@ -164,7 +165,7 @@ void __sched __down_read(struct rw_semaphore *sem)
         list_add_tail(&waiter.list, &sem->wait_list);
 
         /* we don't need to touch the semaphore struct anymore */
-        spin_unlock_irq(&sem->wait_lock);
+        spin_unlock_irqrestore(&sem->wait_lock, flags);
 
         /* wait to be given the lock */
         for (;;) {
@@ -209,13 +210,14 @@ void __sched __down_write_nested(struct rw_semaphore *sem, int subclass)
 {
         struct rwsem_waiter waiter;
         struct task_struct *tsk;
+        unsigned long flags;
 
-        spin_lock_irq(&sem->wait_lock);
+        spin_lock_irqsave(&sem->wait_lock, flags);
 
         if (sem->activity == 0 && list_empty(&sem->wait_list)) {
                 /* granted */
                 sem->activity = -1;
-                spin_unlock_irq(&sem->wait_lock);
+                spin_unlock_irqrestore(&sem->wait_lock, flags);
                 goto out;
         }
 
@@ -230,7 +232,7 @@ void __sched __down_write_nested(struct rw_semaphore *sem, int subclass)
         list_add_tail(&waiter.list, &sem->wait_list);
 
         /* we don't need to touch the semaphore struct anymore */
-        spin_unlock_irq(&sem->wait_lock);
+        spin_unlock_irqrestore(&sem->wait_lock, flags);
 
         /* wait to be given the lock */
         for (;;) {