On Wed, Nov 11, 2020 at 12:13:28PM -0600, Josh Poimboeuf wrote: > On Wed, Nov 11, 2020 at 06:47:36PM +0100, Peter Zijlstra wrote:
> > Yeah, so it's all a giant can of worms that; also see: > > > > https://lkml.kernel.org/r/[email protected] > > > > The basic idea is to only trace edges, ie. when the hardware state > > actually changes. Sadly this means doing a pushf/pop before the cli. > > Ideally CLI would store the old IF in CF or something like that, but > > alas. > > Right, that makes sense for save/restore, but is the disabled check > really needed for local_irq_disable()? Wouldn't that always be an edge? IIRC there is code that does local_irq_disable() even though IRQs are already disabled. This is 'harmless'. > And anyway I don't see a similar check for local_irq_enable(). I know there is code that does local_irq_enable() with IRQs already enabled, I'm not exactly sure why this is different. I'll have to put it on the todo list :/
