Re: [RFC PATCH for 4.16 02/21] rseq: Introduce restartable sequences system call (v12)

On Thu, 14 Dec 2017, Peter Zijlstra wrote:

quoted

But my company has extensive user space code that maintains a lot of
counters and does other tricks to get full performance out of the
hardware. Such a mechanism would also be good from user space. Why keep
the good stuff only inside the kernel?

Mathieu's proposal is for userspace, _only_ userspace.

But what we were talking about are instructions that work effectively in
kernel space whose efficiency restartable sequences could bring to user
space.