Re: [dpdk-dev] [PATCH 19.08 2/6] examples: add support for relocated DPDK install

[Bruce Richardson <bruce.richardson@intel.com>]

On Tue, May 07, 2019 at 04:53:00PM +0100, Luca Boccassi wrote:
> On Tue, 2019-05-07 at 16:17 +0100, Bruce Richardson wrote:
> > On Tue, May 07, 2019 at 02:28:11PM +0100, Luca Boccassi wrote:
> > > On Tue, 2019-05-07 at 11:50 +0100, Bruce Richardson wrote:
> > > > On Tue, May 07, 2019 at 11:09:51AM +0100, Luca Boccassi wrote:
> > > > > On Fri, 2019-05-03 at 14:35 +0100, Bruce Richardson wrote:
> > > > > > For testing of DPDK, we want to override the prefix given by
> > > > > > the
> > > > > > pkg-config file, so that we can get correct paths for DPDK
> > > > > > installed
> > > > > > in an unusual location.
> > > > > > 
> > > > > > Signed-off-by: Bruce Richardson <
> > > > > > bruce.richardson@intel.com
> > > > > > 
> > > > > > 
> > > > > > 
> > > > > > ---
> > > > > >  examples/bbdev_app/Makefile             | 13 +++++++++----
> > > > > >  examples/bond/Makefile                  | 13 +++++++++----
> > > > > >  examples/cmdline/Makefile               | 13 +++++++++----
> > > > > >  examples/distributor/Makefile           | 13 +++++++++----
> > > > > >  examples/eventdev_pipeline/Makefile     | 13 +++++++++----
> > > > > >  examples/exception_path/Makefile        | 13 +++++++++----
> > > > > >  examples/fips_validation/Makefile       | 13 +++++++++----
> > > > > >  examples/flow_classify/Makefile         | 13 +++++++++----
> > > > > >  examples/flow_filtering/Makefile        | 13 +++++++++----
> > > > > >  examples/helloworld/Makefile            | 13 +++++++++----
> > > > > >  examples/ip_fragmentation/Makefile      | 13 +++++++++----
> > > > > >  examples/ip_pipeline/Makefile           | 13 +++++++++----
> > > > > >  examples/ip_reassembly/Makefile         | 13 +++++++++----
> > > > > >  examples/ipsec-secgw/Makefile           | 13 +++++++++----
> > > > > >  examples/ipv4_multicast/Makefile        | 13 +++++++++----
> > > > > >  examples/kni/Makefile                   | 13 +++++++++----
> > > > > >  examples/l2fwd-cat/Makefile             | 13 +++++++++----
> > > > > >  examples/l2fwd-crypto/Makefile          | 13 +++++++++----
> > > > > >  examples/l2fwd-jobstats/Makefile        | 13 +++++++++----
> > > > > >  examples/l2fwd-keepalive/Makefile       | 13 +++++++++----
> > > > > >  examples/l2fwd/Makefile                 | 13 +++++++++----
> > > > > >  examples/l3fwd-acl/Makefile             | 13 +++++++++----
> > > > > >  examples/l3fwd-power/Makefile           | 13 +++++++++----
> > > > > >  examples/l3fwd-vf/Makefile              | 13 +++++++++----
> > > > > >  examples/l3fwd/Makefile                 | 13 +++++++++----
> > > > > >  examples/link_status_interrupt/Makefile | 13 +++++++++----
> > > > > >  examples/load_balancer/Makefile         | 13 +++++++++----
> > > > > >  examples/packet_ordering/Makefile       | 13 +++++++++----
> > > > > >  examples/ptpclient/Makefile             | 13 +++++++++----
> > > > > >  examples/qos_meter/Makefile             | 13 +++++++++----
> > > > > >  examples/qos_sched/Makefile             | 13 +++++++++----
> > > > > >  examples/rxtx_callbacks/Makefile        | 13 +++++++++----
> > > > > >  examples/service_cores/Makefile         | 13 +++++++++----
> > > > > >  examples/skeleton/Makefile              | 13 +++++++++----
> > > > > >  examples/tep_termination/Makefile       | 13 +++++++++----
> > > > > >  examples/timer/Makefile                 | 13 +++++++++----
> > > > > >  examples/vhost/Makefile                 | 13 +++++++++----
> > > > > >  examples/vhost_scsi/Makefile            | 13 +++++++++----
> > > > > >  examples/vmdq/Makefile                  | 13 +++++++++----
> > > > > >  examples/vmdq_dcb/Makefile              | 13 +++++++++----
> > > > > >  40 files changed, 360 insertions(+), 160 deletions(-)
> > > > > > 
> > > > > > diff --git a/examples/bbdev_app/Makefile
> > > > > > b/examples/bbdev_app/Makefile
> > > > > > index e8115b46a..603932ace 100644
> > > > > > --- a/examples/bbdev_app/Makefile
> > > > > > +++ b/examples/bbdev_app/Makefile
> > > > > > @@ -18,10 +18,15 @@ shared: build/$(APP)-shared
> > > > > >  static: build/$(APP)-static
> > > > > >         ln -sf $(APP)-static build/$(APP)
> > > > > >  
> > > > > > -PC_FILE := $(shell pkg-config --path libdpdk)
> > > > > > -CFLAGS += -O3 $(shell pkg-config --cflags libdpdk)
> > > > > > -LDFLAGS_SHARED = $(shell pkg-config --libs libdpdk)
> > > > > > -LDFLAGS_STATIC = -Wl,-Bstatic $(shell pkg-config --static --
> > > > > > libs
> > > > > > libdpdk)
> > > > > > +PKGCONF=pkg-config
> > > > > > +ifneq ($(DPDK_PC_PREFIX),)
> > > > > > +       PKGCONF += --define-variable=prefix=$(DPDK_PC_PREFIX)
> > > > > > +endif
> > > > > > +
> > > > > > +PC_FILE := $(shell $(PKGCONF) --path libdpdk)
> > > > > > +CFLAGS += -O3 $(shell $(PKGCONF) --cflags libdpdk)
> > > > > > +LDFLAGS_SHARED = $(shell $(PKGCONF) --libs libdpdk)
> > > > > > +LDFLAGS_STATIC = -Wl,-Bstatic $(shell $(PKGCONF) --static --
> > > > > > libs
> > > > > > libdpdk)
> > > > > >  
> > > > > >  CFLAGS += -DALLOW_EXPERIMENTAL_API
> > > > > 
> > > > > Hi,
> > > > > 
> > > > > Would using "--define-prefix" allow to avoid the special-sauced
> > > > > DPDK_PC_PREFIX variable?
> > > > > 
> > > > > -- 
> > > > 
> > > > Perhaps I'm missing something, but I'm not seeing how, since the
> > > > code
> > > > above
> > > > is already using the --define-variable flag. Swapping one pkg-
> > > > config
> > > > flag
> > > > for another isn't likely to change the flow. Whatever way things
> > > > work, we
> > > > need an environment variable to pull in the path change. Since
> > > > one
> > > > doesn't
> > > > seem to be available for pkg-config directly, we need a DPDK
> > > > special-
> > > > sauced
> > > > one.
> > > > 
> > > > /Bruce
> > > 
> > > I think PKG_CONFIG_PATH is a more common and more well-understood
> > > flag
> > > to use - using define-prefix should allow to use that instead
> > > 
> > 
> > Yes, except pkg-config-path only gives the path to the pkg-config
> > file, it
> > doesn't affect the prefixes in the file itself, and it's the latter
> > we need
> > to modify.
> 
> Using --define-prefix will automatically adjust the prefixes based on
> the path:
> 
Sorry, I misunderstood what it did - I thought it required the prefix as
parameter, so yes, it looks like a good fit here.

/Bruce