On 4/18/23 10:11, Qais Yousef wrote:
On 03/29/23 14:55, Juri Lelli wrote:Qais reported [1] that iterating over all tasks when rebuilding root domains for finding out which ones are DEADLINE and need their bandwidth correctly restored on such root domains can be a costly operation (10+ ms delays on suspend-resume). He proposed we skip rebuilding root domains for certain operations, but that approach seemed arch specific and possibly prone to errors, as paths that ultimately trigger a rebuild might be quite convoluted (thanks Qais for spending time on this!). To fix the problem 01/06 - Rename functions deadline with DEADLINE accounting (cleanup suggested by Qais) - no functional change 02/06 - Bring back cpuset_mutex (so that we have write access to cpusets from scheduler operations - and we also fix some problems associated to percpu_cpuset_rwsem) 03/06 - Keep track of the number of DEADLINE tasks belonging to each cpuset 04/06 - Create DL BW alloc, free & check overflow interface for bulk bandwidth allocation/removal - no functional change 05/06 - Fix bandwidth allocation handling for cgroup operation involving multiple tasks 06/06 - Use this information to only perform the costly iteration if DEADLINE tasks are actually present in the cpuset for which a corresponding root domain is being rebuilt With respect to the RFC posting [2] 1 - rename DEADLINE bandwidth accounting functions - Qais 2 - call inc/dec_dl_tasks_cs from switched_{to,from}_dl - Qais 3 - fix DEADLINE bandwidth allocation with multiple tasks - Waiman, contributed by Dietmar This set is also available from https://github.com/jlelli/linux.git deadline/rework-cpusetsIs this just waiting to be picked up or still there's something to be addressed still?
There are some changes to cpuset code recently and so I believe that this patch series may need to be refreshed to reconcile the changes.
Thanks, Longman
