In the course of my experiments with rt kernels it so happens that the gui versions of tuna built from upstream (RHEL, F11) SRPMs show wrong affinity settings for IRQ threads.
It wasn't actually a tuna bug but rather misunderstanding on my part. When tuna-0.8.4-1 gui is being used to set IRQ affinity it also changes affinity settings of a related kernel thread. On the other hand rtctl-1.5-1 script can only restore kernel threads affinities. The following rtctl-1.5-1 patch may be used to restore IRQ affinities on system startup according to affinity settings of related kernel threads if needed:
--- /usr/sbin/rtctl.20090912 2009-09-12 19:50:37.000000000 +0400 +++ /usr/sbin/rtctl 2009-09-13 12:14:01.000000000 +0400 @@ -82,6 +83,8 @@ } if (group_affinity[i] != "*") { print "taskset -p " group_affinity[i] " " $1 " > /dev/null" + if (match($2, /[IRQ-(.*)]$/, tmp)) + print "echo " strtonum(group_affinity[i]) " > /proc/irq/" tmp[1] "/smp_affinity" } break }
Sasha