On 08/19/2016 11:57 PM, Jonathan Corbet wrote:
On Fri, 19 Aug 2016 08:33:21 +0800
"Zhou, Wenjian/周文剑" <zhouwj-f...@cn.fujitsu.com> wrote:
I was also confused by maxcpus and nr_cpus before writing this patch.
I think it is a good choice to describe it in kernel-parameters.txt.
Then, only two things need to be done I think.
One is move the above description to maxcpus= in kernel-parameters.txt.
And the other is replace maxcpus with maxcpus/nr_cpus in kdump.txt.
How do you think?
That is not quite what I had in mind, sorry. What I would really like to
see in kernel-parameters.txt is an explanation of how those two parameters
differ - what do they do differently and how should a user choose one over
the other? What we have now offers no guidance in that matter.
I thought about it. I think user may not need this.
What user really want to know is how to choose.
And it is also not a hard work. If nr_cpus is not supported by the ARCH, use
maxcpus.
Otherwise, nr_cpus. The reason why maxcpus still exists is nr_cpus can't be
supported
by some ARCHes.
I think it may be why the author didn't write too much description of it.
I suspect that may be a bit more than you had signed up to do. As an
intermediate step, how about this: rather than tacking on those lines in
kdump.txt, rewrite that paragraph to simply say what the reader should
use. If nr_cpus is good for everybody, just say that, but your previous
patch suggests that the situation isn't quite that simple?
Actually, if nr_cpus always usable, there won't be these discussions.
--
Thanks
Zhou
