Spawning the ctrl threads on anything that is not part of the eal
coremask is not that polite to the rest of the system, especially
when you took good care to pin your processes on cpu resources with
tools like taskset (linux) / cpuset (freebsd).
Rather than introduce yet another eal options to control on which cpu
those ctrl threads are created, let's take the startup cpu affinity
as a reference and remove the eal coremask from it.
If no cpu is left, then we default to the master core.
The cpuset is computed once at init before the original cpu affinity
is lost.
Introduced a RTE_CPU_AND macro to abstract the differences between linux
and freebsd respective macros.
Examples in a 4 cores FreeBSD vm:
$ ./build/app/testpmd -l 2,3 --no-huge --no-pci -m 512 \
-- -i --total-num-mbufs=2048
$ procstat -S 1057
PID TID COMM TDNAME CPU CSID CPU MASK
1057 100131 testpmd - 2 1 2
1057 100140 testpmd eal-intr-thread 1 1 0-1
1057 100141 testpmd rte_mp_handle 1 1 0-1
1057 100142 testpmd lcore-slave-3 3 1 3
$ cpuset -l 1,2,3 ./build/app/testpmd -l 2,3 --no-huge --no-pci -m 512 \
-- -i --total-num-mbufs=2048
$ procstat -S 1061
PID TID COMM TDNAME CPU CSID CPU MASK
1061 100131 testpmd - 2 2 2
1061 100144 testpmd eal-intr-thread 1 2 1
1061 100145 testpmd rte_mp_handle 1 2 1
1061 100147 testpmd lcore-slave-3 3 2 3
$ cpuset -l 2,3 ./build/app/testpmd -l 2,3 --no-huge --no-pci -m 512 \
-- -i --total-num-mbufs=2048
$ procstat -S 1065
PID TID COMM TDNAME CPU CSID CPU MASK
1065 100131 testpmd - 2 2 2
1065 100148 testpmd eal-intr-thread 2 2 2
1065 100149 testpmd rte_mp_handle 2 2 2
1065 100150 testpmd lcore-slave-3 3 2 3
Fixes: d651ee4919cd ("eal: set affinity for control threads")
Cc: stable@dpdk.org
Signed-off-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
Reviewed-by: Olivier Matz <olivier.matz@6wind.com>
c3568ea376