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Subject: Re: Restartable Sequences system call merged into Linux
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Carlos O'Donell <carlos@redhat.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        libc-alpha <libc-alpha@sourceware.org>
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From:   Florian Weimer <fweimer@redhat.com>
Message-ID: <31fc101a-295b-067b-1a82-7e9e509fc92f@redhat.com>
Date:   Mon, 11 Jun 2018 21:55:38 +0200
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On 06/11/2018 09:49 PM, Mathieu Desnoyers wrote:
> It should be noted that there can be only one rseq TLS area registered per thread,
> which can then be used by many libraries and by the executable, so this is a
> process-wide (per-thread) resource that we need to manage carefully.

Is it possible to resize the area after thread creation, perhaps even 
from other threads?

If there is only one contiguous area, this generally means there needs 
to be linker support, similar to what we have for initial-exec TLS today.

Thanks,
Florian