Support CPU affinity on FreeBSD

[oberstet]

It seems, getting/setting CPU affinity is not supported on FreeBSD:

Python 2.7.8 (a980ebb26592ed26706cd33a4e05eb45b5d3ea09, Dec 13 2014, 07:55:06)
[PyPy 2.4.0 with GCC 4.2.1 Compatible FreeBSD Clang 3.4.1 (tags/RELEASE_34/dot1-final 208032)] on freebsd10
Type "help", "copyright", "credits" or "license" for more information.
>>>> import psutil
>>>> psutil.__version__
'2.1.3'
>>>> p = psutil.Process()
>>>> p.cpu_affinity()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'Process' object has no attribute 'cpu_affinity'
>>>>

[giampaolo]

Yes, it's not supported because FreeBSD does not support it.

[oberstet]

FreeBSD does support it: https://www.freebsd.org/cgi/man.cgi?query=cpuset&sektion=2

[giampaolo]

Ah cool! I didn't know that. Added to the TODO list.

[oberstet]

Awesome! psutil rocks.

[giampaolo]

http://sources.freebsd.org/RELENG_9/src/usr.bin/cpuset/cpuset.c is the implementation of the "cpuset" command and looks like the right way to go.

[giampaolo]

Implemented in cd37f64

[oberstet]

Fantastic! I've tested trunk: works as expected .. cool. We are using psutil in https://github.com/crossbario/crossbar .. and this feature is highly appreciated.

Test system: FreeBSD 10.1 amd64 PyPy 2.4

• Building spits out some minor warnings: https://gist.github.com/oberstet/de48b9a7effa4a0754ad
• API works: https://gist.github.com/oberstet/78971b18970c5b1d8744
• And finally, running a TCP echo server with and without affinity set actually shows it does work http://picpaste.com/pics/Clipboard01-sgocv9h8.1420126580.png

Thank you very much! Ah, and happy new year;)

[giampaolo]

Glad you appreciated it and crossbar.io looks like a very interesting project.
I fixed some (not all) warnings in 842e4fb.
Happy new year to you too. =)

[oberstet]

Warnings .. thx! Nearly gone now .. here, just for the record:

cc -O2 -fPIC -Wimplicit -I/usr/local/include -O3 -march=native -I/home/oberstet/pypy1/include -c psutil/_psutil_bsd.c -o build/temp.freebsd-10.1-RELEASE-amd64-2.7/psutil/_psutil_bsd.o
psutil/_psutil_bsd.c:106:1: warning: control reaches end of non-void function [-Wreturn-type]
}
^
psutil/_psutil_bsd.c:1160:44: warning: field precision should have type 'int', but argument has type 'unsigned long' [-Wformat]
                    path, sizeof(path), "%.*s",
                                         ~~^~
psutil/_psutil_bsd.c:2004:41: warning: field precision should have type 'int', but argument has type 'unsigned long' [-Wformat]
        snprintf(path, sizeof(path), "%.*s",
                                      ~~^~
3 warnings generated.