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From: Elad Lahav <e2lahav@gmail.com>
To: perfbook@vger.kernel.org
Subject: Section 7.3.2: Mention of futexes
Date: Fri, 14 Oct 2022 08:01:29 -0400	[thread overview]
Message-ID: <CAJbg=FXoEOio8u72S20cWxJYcu1Z5No7n9bpNOQB8THnVzraqA@mail.gmail.com> (raw)

Hello,

I'm not sure about the statement made in this section: "In contrast,
Linux avoids these hints, in-
stead getting similar results from a mechanism called futexes".
Futexes are just wrappers around kernel mutexes, to speed up the case
of acquiring a free lock. As such they do not solve the priority
inversion problem, and are certainly not a replacement for disabling
pre-emption when using spin locks.
Kernel-level mutexes may address priority inversion by employing one
of the established protocols (priority inheritance or priority
protection).

Am I missing something?

--Elad

             reply	other threads:[~2022-10-14 12:01 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-14 12:01 Elad Lahav [this message]
2022-10-19 22:15 ` Section 7.3.2: Mention of futexes Paul E. McKenney
2022-10-20  0:18   ` Elad Lahav
2022-10-20 10:21     ` Elad Lahav
2022-10-20 16:04       ` Paul E. McKenney

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