Re: [PATCH RT] rt: add rwsem_is_contended() definition to rwsem_rt.h

From: Sebastian Andrzej Siewior
Date: Tue Feb 17 2015 - 05:09:20 EST


* Clark Williams | 2014-08-27 16:09:28 [-0500]:

>Thomas,
>
>The latest btrfs code uses rwsem_is_contended() in the function
>caching_thread(). On RT systems, include/linux/rwsem.h is replaced with
>include/linux/rwsem_rt.h which does not provide a definition for
>rwsem_is_contended(). This commit provides a definition that should
>work on RT (where the lock is actually an rt_mutex).

I see that I added rwsem_is_contended() in v3.14-rt1 which does:
|static inline int rwsem_is_contended(struct rw_semaphore *sem)
|{
| /* rt_mutex_has_waiters() */
| return !RB_EMPTY_ROOT(&sem->lock.waiters);
|}

Do you lack this in kernel prior to v3.14?

Sebastian
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/