Subject: Re: [RFC PATCH v6 1/5] Thread-local ABI system call: cache CPU number
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To: Linus Torvalds <torvalds@linux-foundation.org>,
        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>,
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        Boqun Feng <boqun.feng@gmail.com>
From: Florian Weimer <fweimer@redhat.com>
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Date: Thu, 7 Apr 2016 18:50:20 +0200
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On 04/07/2016 06:39 PM, Linus Torvalds wrote:

> Can anybody give a *coherent* and actual *real* reason why the kernel
> would ever care about anything else?

We already have a similar per-thread data structure, the robust mutex
list.  The CPU ID is another one.  So it's conceivable we might get
further such fields in the future.

(AFAICS set_robust_list was designed with such extensions in mind.)

Florian