On 4/11/2016 9:18 AM, Frederic Weisbecker wrote:
So I tried and it warns about the unused variable tickless_load, so I would need two scattered ifdeffery in the function:@@ -4528,7 +4529,9 @@ decay_load_missed(unsigned long load, unsigned long missed_updates, int idx) static void cpu_load_update(struct rq *this_rq, unsigned long this_load, unsigned long pending_updates) { +#ifdef CONFIG_NO_HZ_COMMON unsigned long tickless_load = this_rq->cpu_load[0]; +#endif
Just move the initialization down to the first use, as a regular assignment, and add __maybe_unused to the declaration, and the compiler will then keep quiet (see Documentation/CodingStyle). I have no comment on which of the approaches looks better overall, but I think using __maybe_unused definitely improves this approach. -- Chris Metcalf, Mellanox Technologies http://www.mellanox.com
