Hey, Op 10-03-15 om 16:28 schreef Peter Zijlstra: > On Tue, Mar 10, 2015 at 03:10:46PM +0100, Maarten Lankhorst wrote: >> Op 10-03-15 om 13:37 schreef Peter Zijlstra: > >>> So IIRC this is the function that checks who gets wounded (and gets to >>> do the whole retry thing), right? >>> >>> So for the RT case, I think we should extend it to not (primarily) be a >>> FIFO thing, but also consider the priority of the tasks involved. >>> >>> Maybe a little something like: >>> >>> if (hold_ctx->task->prio < ctx->task->prio) >>> return -EDEADLOCK; >>> >>> before the timestamp check; although I suppose we should also add a >>> deadline test in case both prios are -1. > >> I think that's useful but if you implement -EDEADLK based on thread >> priority, any boosted thread should receive -EDEADLK when it tries to >> acquire a new lock in the same context, to force it to back off.. > > But _only_ if the boost comes from inside the ww_ctx, right? > > Yeah, implementing that might be tricky, maybe we can keep it as a note > for now ;) Indeed!
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