mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-12 23:56:42 +07:00
7f6c553902
Currently, the q_vector initialization routine sets the affinity_mask of a q_vector based on v_idx value. Meaning a loop iterates on v_idx, which is an incremental value, and the cpumask is created based on this value. This is a problem in systems with multiple logical CPUs per core (like in SMT scenarios). If we disable some logical CPUs, by turning SMT off for example, we will end up with a sparse cpu_online_mask, i.e., only the first CPU in a core is online, and incremental filling in q_vector cpumask might lead to multiple offline CPUs being assigned to q_vectors. Example: if we have a system with 8 cores each one containing 8 logical CPUs (SMT == 8 in this case), we have 64 CPUs in total. But if SMT is disabled, only the 1st CPU in each core remains online, so the cpu_online_mask in this case would have only 8 bits set, in a sparse way. In general case, when SMT is off the cpu_online_mask has only C bits set: 0, 1*N, 2*N, ..., C*(N-1) where C == # of cores; N == # of logical CPUs per core. In our example, only bits 0, 8, 16, 24, 32, 40, 48, 56 would be set. This patch changes the way q_vector's affinity_mask is created: it iterates on v_idx, but consumes the CPU index from the cpu_online_mask instead of just using the v_idx incremental value. No functional changes were introduced. Signed-off-by: Guilherme G Piccoli <gpiccoli@linux.vnet.ibm.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> |
||
---|---|---|
.. | ||
appletalk | ||
arcnet | ||
bonding | ||
caif | ||
can | ||
cris | ||
dsa | ||
ethernet | ||
fddi | ||
fjes | ||
hamradio | ||
hippi | ||
hyperv | ||
ieee802154 | ||
ipvlan | ||
irda | ||
phy | ||
plip | ||
ppp | ||
slip | ||
team | ||
usb | ||
vmxnet3 | ||
wan | ||
wimax | ||
wireless | ||
xen-netback | ||
dummy.c | ||
eql.c | ||
geneve.c | ||
gtp.c | ||
ifb.c | ||
Kconfig | ||
LICENSE.SRC | ||
loopback.c | ||
macsec.c | ||
macvlan.c | ||
macvtap.c | ||
Makefile | ||
mdio.c | ||
mii.c | ||
netconsole.c | ||
nlmon.c | ||
ntb_netdev.c | ||
rionet.c | ||
sb1000.c | ||
Space.c | ||
sungem_phy.c | ||
tun.c | ||
veth.c | ||
virtio_net.c | ||
vrf.c | ||
vxlan.c | ||
xen-netfront.c |