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References: <20200814152557.2128464-1-bdenes@scylladb.com>
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From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Fri, 14 Aug 2020 08:33:43 -0700
Message-ID: <CAMe9rOr4BxZsb4pqM8En63WtpOn3XLH8xa-WQBB3LWyMWKiUvw@mail.gmail.com>
Subject: Re: [RFC PATCH v1] Support inspecting green threads
To: =?UTF-8?Q?Botond_D=C3=A9nes?= <bdenes@scylladb.com>
Cc: GDB <gdb-patches@sourceware.org>
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On Fri, Aug 14, 2020 at 8:29 AM Botond D=C3=A9nes <bdenes@scylladb.com> wro=
te:
>
> Some applications use green threads that have their own stacks. One such
> example is Scylla [1] which is using the seastar framework [2], which
> provides green threads in the form of seastar::thread [3]. These threads
> are created with `setcontext()` and later we switch in/out using
> `setjmp()`/`longjmp()`
>

FYI, Intel CET doesn't allow switching ucontext created by setcontext
with setjmp/longjmp.  setcontext or swapcontext must be used.

--=20
H.J.