From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christopher Lameter <cl@linux.com>
Subject: Re: [RFC PATCH for 4.16 02/21] rseq: Introduce restartable sequences
 system call (v12)
Date: Thu, 14 Dec 2017 15:14:00 -0600 (CST)
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To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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On Thu, 14 Dec 2017, Mathieu Desnoyers wrote:

> If we port this concept to kernel-space (as I start to understand
> would be your wish), then a simple pointer store to the current
> task_struct would suffice.

Certainly such a port would be beneficial for non x86 archs.

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?