Messages in this thread | | | Date | Sun, 4 Jan 2015 08:14:16 -0800 | From | "Paul E. McKenney" <> | Subject | Re: [PATCH v2] srcu: Isolate srcu sections using CONFIG_SRCU |
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On Sun, Jan 04, 2015 at 08:35:52PM +1100, Michael Ellerman wrote: > On Tue, 2014-12-30 at 13:54 -0500, Pranith Kumar wrote: > > On Tue, Dec 30, 2014 at 1:50 PM, Peter Zijlstra <peterz@infradead.org> wrote: > > > On Tue, Dec 30, 2014 at 12:46:22AM -0500, Pranith Kumar wrote: > > >> Isolate the SRCU functions and data structures within CONFIG_SRCU so that there > > >> is a compile time failure if srcu is used when not enabled. This was decided to > > >> be better than waiting until link time for a failure to occur. > > > > > > Why? > > > > This is part of the kernel tinification efforts. The first patch was > > posted here: https://lkml.org/lkml/2014/12/4/848. This patch enables a > > compile time failure instead of a link time failure. > > The punch line was: > > "so the savings are about ~2000 bytes." > > Which is utterly not worth the effort IMO. There have got to be more attractive > targets for tinification than this.
There probably are. But if the tinification effort is to come anywhere near reaching its goals, it is going to need 2000-byte savings, especially on the small systems that are this effort's main target.
That said, Peter's suggestion of falling back to the link-time diagnostic does simplify things a bit, and might be a good approach.
Thanx, Paul
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