On Wed, Jun 01, 2022 at 05:17:36PM +0000, Andrew Cooper wrote:
> On 01/06/2022 17:59, Anthony PERARD wrote:
> > Patch series available in this git branch:
> > https://xenbits.xen.org/git-http/people/aperard/xen-unstable.git
> > br.build-system-xen-include-rework-v1
> >
> > Hi,
> >
> > This patch series is about 2 improvement. First one is to use $(if_changed,
> > )
> > in "include/Makefile" to make the generation of the compat headers less
> > verbose
> > and to have the command line part of the decision to rebuild the headers.
> > Second one is to replace one slow script by a much faster one, and save time
> > when generating the headers.
> >
> > Thanks.
> >
> > Anthony PERARD (4):
> > build: xen/include: use if_changed
> > build: set PERL
> > build: replace get-fields.sh by a perl script
> > build: remove auto.conf prerequisite from compat/xlat.h target
> >
> > xen/Makefile | 1 +
> > xen/include/Makefile | 106 ++++---
> > xen/tools/compat-xlat-header | 539 +++++++++++++++++++++++++++++++++++
> > xen/tools/get-fields.sh | 528 ----------------------------------
>
> Excellent. I was planning to ask you about this. (I also need to
> refreshing my half series cleaning up other bits of the build.)
>
> One trivial observation is that it would probably be nicer to name the
> script with a .pl extension.
Sound fine, I don't think it matter much here.
> Any numbers on what the speedup in patch 3 is?
Yes, on my machine when doing a full build, with `ccache` enabled, it
saves about 1.17 seconds (out of ~17s), and without ccache, it saves
about 2.0 seconds (out of ~37s).
Without ccache:
before:
$ for i in `seq 4`; do time make -j$(nproc) -s O=build 2>/dev/null
>/dev/null; rm -r build; done
make --no-print-directory -j$(nproc) -s O=build > /dev/null 244.98s user
29.24s system 683% cpu 40.146 total
make --no-print-directory -j$(nproc) -s O=build > /dev/null 47.05s user
11.50s system 332% cpu 17.610 total
make --no-print-directory -j$(nproc) -s O=build > /dev/null 47.35s user
11.22s system 330% cpu 17.733 total
make --no-print-directory -j$(nproc) -s O=build > /dev/null 47.31s user
11.23s system 333% cpu 17.577 total
after:
$ for i in `seq 4`; do time make -j$(nproc) -s O=build
2>/dev/null>/dev/null; rm -r build; done
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
237.28s user 25.97s system 667% cpu 39.456 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
37.60s user 8.20s system 282% cpu 16.214 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
37.95s user 8.67s system 279% cpu 16.651 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
38.02s user 8.40s system 280% cpu 16.545 total
And without ccache:
before:
$ for i in `seq 4`; do time make -j$(nproc) -s O=build
2>/dev/null>/dev/null; rm -r build; done
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
206.37s user 22.19s system 640% cpu 35.695 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
221.45s user 22.26s system 667% cpu 36.537 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
233.95s user 23.80s system 686% cpu 37.518 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
234.27s user 23.83s system 680% cpu 37.923 total
after:
$ for i in `seq 4`; do time make -j$(nproc) -s O=build
2>/dev/null>/dev/null; rm -r build; done
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
198.62s user 18.64s system 642% cpu 33.841 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
202.91s user 19.46s system 655% cpu 33.912 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
224.42s user 20.89s system 680% cpu 36.025 total
make --no-print-directory -j$(nproc) -s O=build 2> /dev/null > /dev/null
222.93s user 21.29s system 683% cpu 35.708 total
> Are the generated compat headers identical before and after this
> series? If yes, I'm very tempted to ack and commit it straight away.
Yes, the headers are identical. Hopefully, I've managed to check with
all compat headers enabled, since that depends on .config.
Cheers,
--
Anthony PERARD
