On Thu, Jan 14, 2016 at 09:15:13PM +0100, Peter Zijlstra wrote: > On Thu, Jan 14, 2016 at 11:42:02AM -0800, Leonid Yegoshin wrote: > > An the only point - please use an appropriate SYNC_* barriers instead of > > heavy bold hammer. That stuff was design explicitly to support the > > requirements of Documentation/memory-barriers.txt > > That's madness. That document changes from version to version as to what > we _think_ the actual hardware does. It is _NOT_ a specification. There is work in progress on a specification, but please don't hold your breath. And I am not as optimistic as I might be about any formal specification keeping up with the Linux kernel or with the hardware that it supports. But it seems worth a good try. > You cannot design hardware from that. Its incomplete and fails to > specify a bunch of things. It not a mathematically sound definition of a > memory model. > > Please stop referring to that document for what a particular barrier > _should_ do. Explain what MIPS does, so we can attempt to integrate > this knowledge with our knowledge of PPC/ARM/Alpha/x86/etc. and improve > upon our understanding of hardware and improve the Linux memory model. Please! Thanx, Paul