Subject: Re: [RFC PATCH v6 1/5] Thread-local ABI system call: cache CPU number
 of running thread
To: Peter Zijlstra <peterz@infradead.org>
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Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Russell King <linux@arm.linux.org.uk>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        linux-kernel@vger.kernel.org, linux-api <linux-api@vger.kernel.org>,
        Paul Turner <pjt@google.com>, Andrew Hunter <ahh@google.com>,
        Andy Lutomirski <luto@amacapital.net>,
        Andi Kleen <andi@firstfloor.org>, Dave Watson <davejwatson@fb.com>,
        Chris Lameter <cl@linux.com>, Ben Maurer <bmaurer@fb.com>,
        rostedt <rostedt@goodmis.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Josh Triplett <josh@joshtriplett.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Michael Kerrisk <mtk.manpages@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>
From: Florian Weimer <fweimer@redhat.com>
Message-ID: <57065493.9060200@redhat.com>
Date: Thu, 7 Apr 2016 14:37:39 +0200
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On 04/07/2016 02:25 PM, Peter Zijlstra wrote:

> Do you have a pointer to something I can read? Because I'm clearly not
> understanding the full issue here.

I believe the canonical reference still is this document:

  <https://www.akkadia.org/drepper/tls.pdf>

For newer architectures (ppc64le, aarch64), you'll have to check the
psABI supplements.

Florian