Experimental Physics and
Industrial Control System

Hi Sinisa

Thank you very much for your help as well as Andrew.

Reporting Success!: the server/client example pair works.

Method repeated below for reference (builds HOST and TARGET).
For general use, the key is to introduce $(T_A) HEADER and LIB search paths that are valid for the
cross compile to work. Also, I had to set HAVE_BOOST_PYTHON_NUM_PY = 0, surprised as not in the make config

If we can automate this with a template for "make configure" rather than hacking
the generated file configure/CONFIG_SITE.local, it would be better.

Best regards


Peter


Our embedded system uses buildroot, so that influences where to look for embedded headers and libs.

Proceeded as follows:
make configure EPICS_BASE=$HOME/PROJECTS/EPICS/base \
    EPICS4_DIR=$HOME/PROJECTS/EPICS/base PYTHON_VERSION=3

Modified CONFIG_SITE.local as follows.

pgm@staffa3 pvaPy]$ git diff 5048ae703c1ae1b5bd5e2ec2bea34983b2828c6a
diff --git a/CONFIG_SITE_ACQ400.local b/CONFIG_SITE_ACQ400.local
new file mode 100644
index 0000000..c8e033e
--- /dev/null
+++ b/CONFIG_SITE_ACQ400.local
@@ -0,0 +1,28 @@
+
+ifeq ($(T_A),linux-arm)
+BR_BASE_HDR = $(HOME)/PROJECTS/acq400_buildroot/output/host/arm-buildroot-linux-gnueabihf/sysroot
+BR_BASE_LIB = $(HOME)/PROJECTS/acq400_buildroot/output/target
+PVA_PY_CPPFLAGS = -I$(BR_BASE_HDR)/usr/include -I$(BR_BASE_HDR)/usr/include/python3.8
+PVA_PY_LDFLAGS = -L$(BR_BASE_LIB)/lib -L$(BR_BASE_LIB)/usr/lib
+PVA_PY_SYS_LIBS = boost_python38 python3.8
+PYTHON_VERSION = 3.8
+endif
+
+

diff --git a/src/pvaccess/Makefile b/src/pvaccess/Makefile
index 8e0a376..5581fdb 100644
--- a/src/pvaccess/Makefile
+++ b/src/pvaccess/Makefile
@@ -41,7 +41,7 @@ endif
 
  # Build the Python pvaccess loadable library
 
-LOADABLE_LIBRARY_HOST += pvaccess
+LOADABLE_LIBRARY += pvaccess


... this seems simple enough "when you know how", if you're planning a more canonical method, I'll be happy to try it.


Run time:

acq2106_182> /mnt/local/server.py
pvAccess Server v7.1.1-SNAPSHOT
Active configuration (w/ defaults)
EPICS_PVAS_INTF_ADDR_LIST = 0.0.0.0:5075
EPICS_PVAS_BEACON_ADDR_LIST =
EPICS_PVAS_AUTO_BEACON_ADDR_LIST = YES
EPICS_PVAS_BEACON_PERIOD = 15
EPICS_PVAS_BROADCAST_PORT = 5076
EPICS_PVAS_SERVER_PORT = 5075
EPICS_PVAS_PROVIDER_NAMES = local
Runtime: 27.08; Counter:    100000, Rate: 3.69 [kHz]
Runtime: 71.83; Counter:    200000, Rate: 2.78 [kHz]
Runtime: 122.71; Counter:    300000, Rate: 2.44 [kHz]

acq2106_182> /mnt/local/client.py
STARTING MONITOR for counter at 1590272853.3175964
STOP MONITOR at 1590272913.3814576
FINAL STATS:
counter: Received:   74716 (  1.24 [kHz]); Missed:       0 (  0.00%)




On 22/05/2020 19:46, Veseli, Sinisa wrote:
> Hi,
>
> On 5/22/20 12:10 PM, Peter Milne wrote:
>> Hi Andrew
>>
>> On 22/05/2020 16:27, Johnson, Andrew N. wrote:
>>> Hi Peter,
>>>
>>> On May 22, 2020, at 3:23 AM, Peter Milne via Tech-talk
>>> <tech-talk at aps.anl.gov<mailto:tech-talk at aps.anl.gov>> wrote:
>>>
>>> We have a requirement to run pvaPy on a linux-arm system.
>>> The ARM system is configured to provide a full EPICS7, Boost lib.
>>>
>>> Following
>>> https://github.com/epics-base/pvaPy/blob/master/README.md
>>>
>>> Custom Build:
>>>
>>> Seems to build fine for EPICS_HOST_ARCH=linux-x86_64
>>>
>>> It's also putting in hooks for linux-arm:
>>> ls ./src/pvaccess/O.linux-arm
>>> Makefile
>>>
>> ...
>>> pgm TOP ../../.. T_A linux-arm
>>> make[3]: Nothing to be done for 'install'.
>>> make[3]: Leaving directory
>>> '/home/pgm/PROJECTS/EPICS/pvaPy/src/pvaccess/O.linux-arm'
>>> make[2]: Leaving directory '/home/pgm/PROJECTS/EPICS/pvaPy/src/pvaccess'
>>> make[1]: Leaving directory '/home/pgm/PROJECTS/EPICS/pvaPy/src'
>>>
>>>
>>> .... does nothing..
>>>
>>>
>>> Is there any way to enable a cross-compile?
>>> I don't see any PROD_HOST entries that could be changed to PROD, for
>>> example.
>>>
>>>
>>> The important entry in src/pvaccess/Makefile is the line
>>>
>>> LOADABLE_LIBRARY_HOST += pvaccess
>>>
>>> Since pvaPy is a dynamic library that gets loaded by Python, there
>>> are no binaries to create so no use of the PROD or PROD_HOST
>>> variables in the Makefile. Change the above to LOADABLE_LIBRARY and
>>> it should start cross-compiling for your target.
>>>
>> Yes, that's it!. Thank you. And, really generically the same idea as
>> PROD_HOST, should have spotted that.
>>
>> So, the good news, it's trying to build.
>> The bad news, there are errors, maybe just one:
>>
>> /usr/include/python3.7m/pyconfig.h:4:10: fatal error: pyconfig-32.h:
>>
>> So the next step is to get it to look at the linux-arm version of the
>> python headers rather than the HOST version..
>>
>> ... and that suddenly becomes really site-specific..
>>
>>
> The build looks into configure/CONFIG_SITE.local file to determine any
> site specific settings, which might also include a custom python build.
>
> Specifically, variables that can be modified are PVA_PY_CPPFLAGS and
> PVA_PY_LDFLAGS. In one of my builds I have the following:
>
> bluegill2> more configure/CONFIG_SITE.local
> PVA_PY_CPPFLAGS = -I/local/sveseli/MARTY/CONDA/include/python3.7m
> -I/local/sveseli/MARTY/opt/boost-python-1.70.0/include
> PVA_PY_LDFLAGS = -L/local/sveseli/MARTY/CONDA/lib
> -L/local/sveseli/MARTY/opt/boost-python-1.70.0/lib/linux-x86_64 -lpython3.7m
> PVA_PY_SYS_LIBS = boost_python37  boost_numpy37
> PVA_API_VERSION = 482
> PVA_RPC_API_VERSION = 482
> HAVE_BOOST_NUM_PY = 0
> HAVE_BOOST_PYTHON_NUM_PY = 1
> PYTHON_VERSION = 3.7
> PVA_PY_PYTHON = /local/sveseli/MARTY/CONDA/bin/python3
> PVA_PY_PYTHONPATH =
> /local/sveseli/MARTY/pvapy-sv/lib/python/3.7/linux-x86_64
> PVA_PY_LD_LIBRARY_PATH =
> /local/sveseli/MARTY/CONDA/lib:/local/sveseli/MARTY/opt/boost-python-1.70.0/lib/linux-x86_64
> PVA_PY_SPHINX_BUILD = /local/sveseli/MARTY/CONDA/bin/sphinx-build
> PVA_PY_EPICS_BASE = /local/sveseli/MARTY/opt/epics-7.0.3.1
> PVA_PY_EPICS4_DIR = /local/sveseli/MARTY/opt/epics-7.0.3.1
> PVA_PY_HOST_ARCH = linux-x86_64
> PVA_PY_SETUP_SH =
> /local/sveseli/MARTY/pvapy-sv/bin/linux-x86_64/pvapy_setup_full.3.7.sh
>
> Automatic configuration should work for the host architecture that you
> are building on, but at the moment it will likely not work for
> cross-compiles.
>>
>>
>>> Hopefully you and Sinisa can work out some way to adjust the build so
>>> cross-builds like this can be configured more easily, but I suspect
>>> it may always need some kind of manual configuration to enable it.
>>
>> .. as confirmed above.
>>
>> Should be possible to make a configure/ option of course..
>>
>> Thanks again Andrew
>>
>> Cheers
>>
>>
> I talked to Andrew about making this easier.
>
> Sinisa
>
>
>> Peter
>>
>>
>>
>>>
>>> - Andrew
>>>
>>>
>>> --
>>> Complexity comes for free, simplicity you have to work for.
>>>
>>>
>>
>>
>


--
Peter Milne
Director of Sales
www.d-tacq.com