Note: This is a beta release of Red Hat Bugzilla 5.0. The data contained within is a snapshot of the live data so any changes you make will not be reflected in the production Bugzilla. Also email is disabled so feel free to test any aspect of the site that you want. File any problems you find or give feedback here.

Bug 454270

Summary: SCHED_FIFO spec violation
Product: Red Hat Enterprise MRG Reporter: IBM Bug Proxy <bugproxy>
Component: realtime-kernelAssignee: Peter Zijlstra <pzijlstr>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: low    
Version: betaCC: bhu, davids, lwang, williams
Target Milestone: 1.0.3   
Target Release: ---   
Hardware: All   
OS: All   
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2008-10-07 19:21:34 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Description Flags
[PATCH] Enqueue deprioritized RT tasks to head of prio array none

Description IBM Bug Proxy 2008-07-07 12:08:21 UTC
=Comment: #0=================================================
Darren V. Hart <> - 2008-07-03 13:10 EDT
According to the SUS, when a SCHED_FIFO task's priority is lowered, it should be
added to the head of the corresponding priority array:

Peter Z. noticed this and wrote a patch to address it:

The dequeue_rt_stack() apparently still needs some work according to peterz

=Comment: #2=================================================
Darren V. Hart <> - 2008-07-03 13:22 EDT
The enqueue_task changed in 2.6.25, so a backport will be required.  It's a
simple patch, so that shouldn't pose a problem.

=Comment: #3=================================================
Darren V. Hart <> - 2008-07-03 15:01 EDT
I've backported the patch and have an R2 patch ready.  Currently under test on
elm3b172 running
=Comment: #4=================================================
Darren V. Hart <> - 2008-07-03 18:27 EDT

[PATCH] Enqueue deprioritized RT tasks to head of prio array

The attached patch is currently undergoing release-testing.

Comment 1 IBM Bug Proxy 2008-07-07 12:08:24 UTC
Created attachment 311140 [details]
[PATCH] Enqueue deprioritized RT tasks to head of prio array

Comment 2 Clark Williams 2008-08-20 13:46:33 UTC
Are we good with this one?

Comment 3 IBM Bug Proxy 2008-08-20 17:00:53 UTC
(In reply to comment #11)
> ------- Comment From 2008-08-20 09:46:33 EDT-------
> Are we good with this one?


Comment 5 David Sommerseth 2008-10-06 16:38:27 UTC
Verified by code review

Comment 7 errata-xmlrpc 2008-10-07 19:21:34 UTC
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.