[CentOS] [SOLVED] Quo vadis?

Sun Sep 13 09:04:51 UTC 2009
A. Kirillov <nevis2us at infoline.su>

> 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