powerpc/time: Remove unnecessary sanity check of decrementer expiration

[deliverable/linux.git] / arch / powerpc / kernel / perf_callchain.c

diff --git a/arch/powerpc/kernel/perf_callchain.c b/arch/powerpc/kernel/perf_callchain.c
index d05ae4204bbf3d3ddcc84266476b736a6790715c..564c1d8bdb5c4f1a3d2768863c56942efb863b14 100644 (file)
--- a/arch/powerpc/kernel/perf_callchain.c
+++ b/arch/powerpc/kernel/perf_callchain.c
@@ -154,8 +154,12 @@ static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret)
            ((unsigned long)ptr & 7))
                return -EFAULT;
 
-       if (!__get_user_inatomic(*ret, ptr))
+       pagefault_disable();
+       if (!__get_user_inatomic(*ret, ptr)) {
+               pagefault_enable();
                return 0;
+       }
+       pagefault_enable();
 
        return read_user_stack_slow(ptr, ret, 8);
 }
@@ -166,8 +170,12 @@ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
            ((unsigned long)ptr & 3))
                return -EFAULT;
 
-       if (!__get_user_inatomic(*ret, ptr))
+       pagefault_disable();
+       if (!__get_user_inatomic(*ret, ptr)) {
+               pagefault_enable();
                return 0;
+       }
+       pagefault_enable();
 
        return read_user_stack_slow(ptr, ret, 4);
 }
@@ -294,11 +302,17 @@ static inline int current_is_64bit(void)
  */
 static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
 {
+       int rc;
+
        if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) ||
            ((unsigned long)ptr & 3))
                return -EFAULT;
 
-       return __get_user_inatomic(*ret, ptr);
+       pagefault_disable();
+       rc = __get_user_inatomic(*ret, ptr);
+       pagefault_enable();
+
+       return rc;
 }
 
 static inline void perf_callchain_user_64(struct perf_callchain_entry *entry,