Messages in this thread | ![/](/images/icornerl.gif) | | Subject | Re: Further copy_from_user() discussion. | From | Catalin Marinas <> | Date | Fri, 15 Apr 2005 11:14:28 +0100 |
| |
Vadim Lobanov <vlobanov@speakeasy.net> wrote: > I think I misspoke a bit in my email above. The intent was not to > eliminate all might_sleep() calls from the copy_from_user() code path; > but rather juggle the source around a bit so there is only one > might_sleep() call per each code path. Currently, in the default case, > it calls it twice. > > By the way, is the following still true about might_sleep()? > http://kerneltrap.org/node/3440/10103
With Ingo's realtime-preempt patch, might_sleep() expands to might_resched(). The latter expands to cond_resched() only if CONFIG_PREEMPT_VOLUNTARY is enabled (for CONFIG_PREEMPT_RT this is not needed since the kernel is involuntarily preemptible). In this case it might be useful to have might_sleep() only called before memset().
-- Catalin
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| ![\](/images/icornerr.gif) |