> -----Original Message----- > From: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com> > Sent: Tuesday, March 9, 2021 4:09 PM > To: Jerin Jacob <jerinjac...@gmail.com>; Juraj Linkeš > <juraj.lin...@pantheon.tech> > Cc: Bruce Richardson <bruce.richard...@intel.com>; Ruifeng Wang > <ruifeng.w...@arm.com>; vcchu...@amazon.com; Dharmik Thakkar > <dharmik.thak...@arm.com>; hemant.agra...@nxp.com; Ajit Khaparde > (ajit.khapa...@broadcom.com) <ajit.khapa...@broadcom.com>; > ferruh.yi...@intel.com; abo...@pensando.io; lir...@marvell.com; > dev@dpdk.org; nd <n...@arm.com>; nd <n...@arm.com> > Subject: RE: [PATCH v16 1/3] build: disable/enable drivers in Arm builds > > <snip> > > > > > > > > > On Tue, Mar 09, 2021 at 08:58:39AM +0000, Juraj Linkeš wrote: > > > > > Honnappa, Thomas, Bruce, Jerin, you've comments in the past. Do > > > > > you have > > > > any further input? > > > > > > > > > > I think we just need to agree on the allowlist/blocklist > > > > > mechanism. The current > > > > commit allows specifying either an allowlist or a blocklist, but not > > > > both. > > > > However, it would possible to implement specifying both - first > > > > we'll allow what's in allowlist and then we'll remove from that > > > > set what's > > in blocklist. > > > > Thoughts? > > > > > > > > > > > > > If we have both, I think limiting to only one is by far the sanest > > > > option. > +1 > > > > > I'm not fully convinced by the need to have both, since the > > > > blocklist allows wildcarding and exception cases. For example > > > > "net/[!i]*" will blocklist all net drivers except those starting > > > > with an "i". Admittedly, for usability purposes having an > > > > allowlist might > > work better. > > > > > > > > > > If we only want to build a handful of drivers then the list could be > > > very long > > (which was the original reason behind having an allowlist), such as here: > > > https://gerrit.fd.io/r/gitweb?p=vpp.git;a=blob;f=build/external/pack > > > ag es/dpdk.mk;h=c35ac84c27b19411a0cfdf9a3524fdf36024762c;hb=HEAD > > > > > > An allowlist could also help with maintenance - users won't need to > > > add > > new drivers to their blocklists (if that's what users need, like in > > the case of VPP). > > > > +1 for allowlist. > May be I am missing something here. By creating an allowlist, does it mean > drivers are disabled (from compilation) by default? For a server platform, > where > almost all the drivers can be compiled, does the allowlist contain all the > drivers? >
If no allowlist is specified, then everythin will be built - nothing will be filtered. > If we assume by default everything should compile on Arm platform, but allow > for few exceptions (where things are really painful to fix, for ex: compiler > needs > to be fixed), having a blocklist should be shorter/better? > The blocklist is, I think, agreed upon by everyone. The question is whether we want to support the allowlist alongside it and there seem to be enough reasons to do that. > By having an allowlist, we will end up with a large part of the code that > might > not compile on Arm platforms. > > > > > > > > > > One final thought, if we add a driver allowlist for cross files, > > > > should we also add one as a top-level meson option also for consistency? > > > > > > > > > > This definitely makese sense. I was thinking about this and wasn't > > > sure > > whether I should put it into this commit or a separate one. The commit > > evolved a bit and now that it's just an implementation of an > > allow/blocklist it makes sense to include a meson option in it I think > > - I'll put it into the next version. > > > > > > > /Bruce > > >
