On Fri, Dec 28, 2018 at 06:25:37PM +0100, Vincent Guittot wrote: > > done without extra space as long as each node has the parent pointer, > > which they do. Is the dedicated list an optimization? > > It prevents to parse and walk all task group struct every time. > Instead, you just have to follow a linked list
Hmmm... I'm having a bit of a hard time imagining doing an actual traversal being a meaningful optimization. It may require more branches but that shouldn't be expensive at all, especially compared to walking all idle groups in the system each time which the code used to do. Anyways, this is tangential. Thanks for the explanation and happy new year! -- tejun