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Date:   Wed, 21 Apr 2021 08:57:48 -0700
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Yury Norov <yury.norov@gmail.com>, linux-kernel@vger.kernel.org,
        rcu@vger.kernel.org, linux-doc@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Palmer Dabbelt <palmerdabbelt@google.com>,
        Paul Gortmaker <paul.gortmaker@windriver.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>
Subject: Re: [PATCH 1/2] bitmap_parse: support 'all' semantics
Message-ID: <20210421155748.GU975577@paulmck-ThinkPad-P17-Gen-1>
Reply-To: paulmck@kernel.org
References: <20210421031326.72816-1-yury.norov@gmail.com>
 <20210421031326.72816-2-yury.norov@gmail.com>
 <20210421111932.36665920@gandalf.local.home>
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On Wed, Apr 21, 2021 at 11:19:32AM -0400, Steven Rostedt wrote:
> On Tue, 20 Apr 2021 20:13:25 -0700
> Yury Norov <yury.norov@gmail.com> wrote:
> 
> > @@ -76,6 +76,11 @@ to change, such as less cores in the CPU list, then N and any ranges using N
> >  will also change.  Use the same on a small 4 core system, and "16-N" becomes
> >  "16-3" and now the same boot input will be flagged as invalid (start > end).
> >  
> > +The special case-tolerant group name "all" has a meaning of selecting all CPUs,
> > +such that "isolcpus=all" is the equivalent of "isolcpus=0-N".
> 
> I'm OK with the concept of this patch set, but really? That is a horrible
> example. One should NEVER set isolcpus to all!

How about "isolcpus=all:2/4"?  ;-)

							Thanx, Paul

> -- Steve
> 
> 
> > +
> > +The semantics of "N" and "all" is supported on a level of bitmaps and holds for
> > +all users of bitmap_parse().
> >