From: Yubin Ruan <ablacktshirt@gmail.com>
To: perfbook@vger.kernel.org
Subject: [Question] Quick Quiz B.13 help
Date: Mon, 13 Feb 2017 21:41:46 +0800 [thread overview]
Message-ID: <3fabc59b-f542-a121-3764-c4ac9eedc062@gmail.com> (raw)
Quick quiz B.13:
Suppose that lines 3-5 for CPUs 1 and 2 in Table B.4 are in an
interrupt handler, and that the CPU 2's line 9 is running at process
level. What changes, if any, are required to enable the code to work
correctly, in other words, to prevent the assertion from firing?
I can not come up with any practical material for this quiz, because I
don't really know the implication of "in an interrupt handler", and
"running in process level".
The answer hints that one would need to ensure that the load of "e"
precedes that of "a" and hint the Linux kernel implementation
"barrier()". But how is that exactly? I am going to invest some time
into the Linux kernel implementation. But I would really appreciate some
hints about this, as I don't have so much kernel development experience
before.
regards,
Yubin Ruan
next reply other threads:[~2017-02-13 13:41 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-13 13:41 Yubin Ruan [this message]
2017-02-13 19:00 ` [Question] Quick Quiz B.13 help Paul E. McKenney
2017-02-14 10:53 ` Yubin Ruan
2017-02-14 15:36 ` Akira Yokosawa
2017-02-16 19:13 ` Paul E. McKenney
2017-02-16 22:47 ` Akira Yokosawa
2017-02-19 22:22 ` Paul E. McKenney
2017-02-19 23:47 ` Akira Yokosawa
2017-02-20 0:51 ` Paul E. McKenney
2017-02-20 1:56 ` Akira Yokosawa
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