cputime: Fix nsecs_to_cputime() return type cast

Even though nsec based cputime_t maps to u64, nsecs_to_cputime() must
return a cputime_t value. We want to enforce this kind of cast in order
to track down buggy manipulations of cputime_t such as direct access
of its values under wrong assumptions on its backend type (nsecs,
jiffies, etc...) by core code.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

diff --git a/include/asm-generic/cputime_nsecs.h b/include/asm-generic/cputime_nsecs.h
index 2c9e62c2bfd03cce685243832d5db4c8e71ec04c..768294f8bf85ed203d41c0852d77d37a662d5946 100644 (file)
--- a/include/asm-generic/cputime_nsecs.h
+++ b/include/asm-generic/cputime_nsecs.h
@@ -44,7 +44,8 @@ typedef u64 __nocast cputime64_t;
 /*
  * Convert cputime <-> nanoseconds
  */
-#define nsecs_to_cputime(__nsecs)      ((__force u64)(__nsecs))
+#define nsecs_to_cputime(__nsecs)      \
+       (__force cputime_t)(__nsecs)
 
 
 /*