On 24/08/02 05:40PM, Thomas Weißschuh wrote: > On 2024-08-01 22:27:45+0000, Jose Fernandez wrote: > > On 24/08/01 12:20PM, Nathan Chancellor wrote: > > > On Thu, Aug 01, 2024 at 08:53:54PM +0200, Thomas Weißschuh wrote: > > > > On 2024-08-01 11:36:37+0000, Nathan Chancellor wrote: > > > > > On Thu, Aug 01, 2024 at 07:29:40AM -0600, Jose Fernandez wrote: > > > > > > Add a new -debug package to the pacman PKGBUILD that will contain the > > > > > > vmlinux image for debugging purposes. This package depends on the > > > > > > -headers package and will be installed in /usr/src/debug/${pkgbase}. > > > > > > > > > > > > The vmlinux image is needed to debug core dumps with tools like crash. > > > > > > > > > > > > Signed-off-by: Jose Fernandez <jose.fernandez@xxxxxxxxx> > > > > > > Reviewed-by: Peter Jung <ptr1337@xxxxxxxxxxx> > > > > > > > > > > This appears to add a non-trivial amount of time to the build when benchmarking > > > > > with Arch Linux's configuration (I measure 9% with hyperfine): > > > > > > > > As nothing more is compiled, I guess this is just the additional > > > > packaging. > > > > > > > > > Benchmark 1: pacman-pkg @ 21b136cc63d2 ("minmax: fix up min3() and max3() too") > > > > > Time (mean ± σ): 579.541 s ± 0.585 s [User: 22156.731 s, System: 3681.698 s] > > > > > Range (min … max): 578.894 s … 580.033 s 3 runs > > > > > > > > > > Benchmark 2: pacman-pkg @ c5af4db0563b ("kbuild: add debug package to pacman PKGBUILD") > > > > > Time (mean ± σ): 633.419 s ± 0.972 s [User: 22247.886 s, System: 3673.879 s] > > > > > Range (min … max): 632.302 s … 634.070 s 3 runs > > > > > > > > > > Summary > > > > > pacman-pkg @ 21b136cc63d2 ("minmax: fix up min3() and max3() too") ran > > > > > 1.09 ± 0.00 times faster than pacman-pkg @ c5af4db0563b ("kbuild: add debug package to pacman PKGBUILD") > > > > > > Hi Nathan, > > Thanks for taking the time to benchmark the change. I did notice that the build > > time for the -debug package felt a bit longer than I expected. I attributed it > > to having to package a large file. > > > > > > > It would be nice to add some option to avoid building this package for > > > > > developers who may not want it (I know I personally would not want it > > > > > with that penalty because I do a lot of bisects) or maybe adding a > > > > > target to build this package with the rest like 'pacman-pkg-with-dbg' or > > > > > something? > > > > My original idea was to add a make config to enable the -debug package, ie: > > `make pacman-pkg DEBUG=1`. Your suggestion of a separate target is also a good > > idea. I don't have strong opinion on this, so I'm open to what you and Thomas > > prefer. > > I'm also in favor of a variable. > The new target would be implemented through a variable anyways. > Instead of a specific variable it should be more generic. > The -api-headers package is most likely used even less than the debug one. > > PACMAN_EXTRAPACKAGES="headers api-headers debug" > (Assuming the main kernel package will always be built) Thomas, I will work a new patch that adds a PACMAN_EXTRAPACKAGES variable to determine which extra packages to build. The main kernel package will always be built, and we will stop building -headers and -api-headers by default. To confirm, this also means I should remove the CONFIG_MODULES check from the PKGBUILD, correct? > > > > > > Also, couldn't vmlinux be obtained from vmlinuz that already > > > > > exists in the main package via scripts/extract-vmlinux? > > > > I didn't know you could do that. However, I suspect that more people will > > encounter this issue and will want the vmlinux file available without knowing > > you can extract it from vmlinuz. I think it's better to have it available > > explicitly in a package. > > Agreed. > > > > > > > > > Jose: > > > > > > > > In the vanilla PKGBUILD vmlinux is part of the linux-headers package: > > > > linux-headers /usr/lib/modules/6.10.2-arch1-1/build/vmlinux > > > > > > > > Given that you already gate the new -debug package on CONFIG_MODULES, > > > > why not add the file to that package? > > > > Hi Thomas, > > My only concern with that approach is that it won't address Nathan's concern > > about increasing the build time. I think an opt-in -debug package is the best > > solution to address this. > > > > Additionally, Peter from CachyOS (cced) shared this merge request with me: > > https://gitlab.archlinux.org/archlinux/packaging/packages/linux/-/merge_requests/3 > > > > It looks like the vanilla PKGBUILD will start including a debug package as well. > > I think it may be good to align with the pattern they will be using. > > This looks very good. But I it seems it will be some time pacman 7.0 > will be available (especially in the derivate distros) > Also even with this the custom configuration mechanism would still be > used. > > > > > > > > > Then we could still discuss if it makes sense to gate vmlinux on > > > > CONFIG_MODULES or if -headers should be enabled unconditionally again. > > > > > > I think having -headers be enabled/built by default is probably okay > > > since a regular user/builder might have external modules that need to be > > > rebuilt against the new kernel. However, I (and likely many other > > > upstream developers, however many use Arch) never build external modules > > > against my kernels, so it would be nice to have some way to opt out of > > > this penalty. I suspect it is just compressing down such a massive > > > vmlinux that causes this? I have not had access to a build log with my > > > testing, so unsure. > > > > > > > Or we wait for somebody to show up and ask for it. > > > > > > I won't insist though so if we want to wait for someone else, that's > > > fine with me too. > > > > I will lean on your preference for how to proceed with this. I'm happy to make > > the changes you think are best. To me, it appears that the next iteration to > > satisfy everyone is to make the -debug package opt-in via a new make target or > > a make config option. > > Ack.