Re: [PATCH v2 0/4] Clean up EAL runtime data paths

[Thomas Monjalon <thomas@monjalon.net>]

09/05/2018 18:11, Bruce Richardson:
> On Wed, May 09, 2018 at 04:59:39PM +0100, Van Haaren, Harry wrote:
> > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Anatoly Burakov
> > > Sent: Monday, April 30, 2018 1:09 PM
> > > To: dev@dpdk.org
> > > Cc: Richardson, Bruce <bruce.richardson@intel.com>; thomas@monjalon.net
> > > Subject: [dpdk-dev] [PATCH v2 0/4] Clean up EAL runtime data paths
> > > 
> > > As has been suggested [1], all DPDK runtime paths should be put
> > > into a single place. This patchset accomplishes exactly that.
> > > 
> > > If running as root, all files will be put under /var/run/dpdk/<prefix>,
> > > otherwise they will be put under $XDG_RUNTIME_PATH/dpdk/<prefix>, or, if
> > > that environment variable is not defined, all files will go under
> > > /tmp/dpdk/<prefix>.
> > > 
> > > [1] http://dpdk.org/dev/patchwork/patch/38688/
> > > 
> > > v2:
> > > - Rebase on rc1
> > > 
> > > Anatoly Burakov (4):
> > >   eal: remove unused define
> > >   eal: rename function returning hugepage data path
> > >   eal: add directory for DPDK runtime data
> > >   eal: move all runtime data into DPDK runtime dir
> > 
> > <snip>
> > 
> > 
> > No full code review, high level comments:
> > 
> > We have to be careful in changing /var/run/.rte_config, which has always been
> > the default DPDK primary application lockfile. This has been used to identify
> > if a primary DPDK application is alive (see rte_eal_primary_proc_alive()) and
> > possibly the write-lock on this file is checked by other tools/utilities directly
> > without any DPDK function call.
> > 
> > Changing the filepath just before a release isn't a good idea - we should treat
> > this as an ABI/API break, as the change will break functionality in other projects
> > such as CollectD[1], which (by default ;) rely on the defaults. There is a config
> > file for CollectD to manually override the location, but this will cause headaches
> > from a usability POV.
> > 
> > I'm not opposed to the change - particularly as I gather the new memory subsystem
> > causes a number of lockfiles to be created - but we must do our due diligence and
> > give other projects fair-warning that this change is coming.
> > 
> > As such, I recommend this patchset in its current form (particularly patches 2,3,4)
> > to be deferred past 18.05.
> > 
> > 
> What about if we keep the .rte_config file in the same place but move the
> rest? The number of new files causes quite a bit of clutter. We can then
> have a deprecation notice for the move in 18.05 and finish the cleanup in
> 18.08.

I agree