Description of problem: As noted by Ben Hutchings in https://bugzilla.redhat.com/show_bug.cgi?id=556476#c15: The patch "linux-2.6-misc-add-thread-core-_siblings_list-to-sys.patch" renames the macros topology_core_siblings and topology_thread_siblings to topology_core_cpumask and topology_thread_cpumask. sfc attempts to allocate one set of queues per package, falling back to one per core. It uses the macro topology_core_siblings, if defined, and therefore will always use the fallback now. Also, the topology_*_cpumask macros return a different type from their mainline implementations, so I don't think the renaming makes sense. Version-Release number of selected component (if applicable): kernel-2.6.18-220.el5 How reproducible: always Steps to Reproduce: 1. use a machine with a Solarflare NIC (sfc driver) 2. cat /proc/interrupts Actual results: The card (eth2 in my case) uses one MSI-X interrupt (associated with a queue) per processor. E.g. with CPU Intel Xeon W3520 (4 cores + hyperthreading): 98: 0 ... 0 PCI-MSI-X eth2-0 106: 0 ... 0 PCI-MSI-X eth2-1 114: 0 ... 0 PCI-MSI-X eth2-2 122: 0 ... 0 PCI-MSI-X eth2-3 130: 0 ... 0 PCI-MSI-X eth2-4 138: 0 ... 0 PCI-MSI-X eth2-5 146: 0 ... 0 PCI-MSI-X eth2-6 154: 0 ... 0 PCI-MSI-X eth2-7 Expected results: The card should use one MSI-X interrupt per CPU package: 90: 0 ... 0 PCI-MSI-X eth2-0
Created attachment 446999 [details] [PATCH] topology: rename topology_{thread,core}_cpumask back to *_siblings Brew build: https://brewweb.devel.redhat.com/taskinfo?taskID=2754167
Notes for QE: It can be tested that the patch does not change the values in /sys/devices/system/cpu/cpu*/topology/*_siblings* I have Solarflare cards and can test the sfc driver.
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
http://post-office.corp.redhat.com/archives/rhkernel-list/2010-September/msg00640.html
in kernel-2.6.18-222.el5 You can download this test kernel from http://people.redhat.com/jwilson/el5 Detailed testing feedback is always welcomed.
On my machine with kernel-2.6.18-221.el5 an sfc interface took 8 interrupts (one per logical processor). With kernel-2.6.18-222.el5 I get allocated one interrupt for an sfc interface. I have one CPU package, so this is as expected.
I'm satisfied that this is fixed in kernel-2.6.18-222.el5.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2011-0017.html