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charset=us-ascii Content-Disposition: inline In-Reply-To: On 18/02/25 15:12, Dietmar Eggemann wrote: > On 18/02/2025 10:58, Juri Lelli wrote: > > Hi! > > > > On 17/02/25 17:08, Juri Lelli wrote: > >> On 14/02/25 10:05, Jon Hunter wrote: > > > > ... > > > >> At this point I believe you triggered suspend. > >> > >>> [ 57.290150] Freezing remaining freezable tasks completed (elapsed 0.001 seconds) > >>> [ 57.335619] tegra-xusb 3530000.usb: Firmware timestamp: 2020-07-06 13:39:28 UTC > >>> [ 57.353364] dwc-eth-dwmac 2490000.ethernet eth0: Link is Down > >>> [ 57.397022] Disabling non-boot CPUs ... > >> > >> Offlining CPU5. > >> > >>> [ 57.400904] dl_bw_manage: cpu=5 cap=3072 fair_server_bw=52428 total_bw=209712 dl_bw_cpus=4 type=DYN span=0,3-5 > >>> [ 57.400949] CPU0 attaching NULL sched-domain. > >>> [ 57.415298] span=1-2 > >>> [ 57.417483] __dl_sub: cpus=3 tsk_bw=52428 total_bw=157284 span=0,3-5 type=DYN > >>> [ 57.417487] __dl_server_detach_root: cpu=0 rd_span=0,3-5 total_bw=157284 > >>> [ 57.417496] rq_attach_root: cpu=0 old_span=NULL new_span=1-2 > >>> [ 57.417501] __dl_add: cpus=3 tsk_bw=52428 total_bw=157284 span=0-2 type=DEF > >>> [ 57.417504] __dl_server_attach_root: cpu=0 rd_span=0-2 total_bw=157284 > >>> [ 57.417507] CPU3 attaching NULL sched-domain. > >>> [ 57.454804] span=0-2 > >>> [ 57.456987] __dl_sub: cpus=2 tsk_bw=52428 total_bw=104856 span=3-5 type=DYN > >>> [ 57.456990] __dl_server_detach_root: cpu=3 rd_span=3-5 total_bw=104856 > >>> [ 57.456998] rq_attach_root: cpu=3 old_span=NULL new_span=0-2 > >>> [ 57.457000] __dl_add: cpus=4 tsk_bw=52428 total_bw=209712 span=0-3 type=DEF > >>> [ 57.457003] __dl_server_attach_root: cpu=3 rd_span=0-3 total_bw=209712 > >>> [ 57.457006] CPU4 attaching NULL sched-domain. > >>> [ 57.493964] span=0-3 > >>> [ 57.496152] __dl_sub: cpus=1 tsk_bw=52428 total_bw=52428 span=4-5 type=DYN > >>> [ 57.496156] __dl_server_detach_root: cpu=4 rd_span=4-5 total_bw=52428 > >>> [ 57.496162] rq_attach_root: cpu=4 old_span=NULL new_span=0-3 > >>> [ 57.496165] __dl_add: cpus=5 tsk_bw=52428 total_bw=262140 span=0-4 type=DEF > >>> [ 57.496168] __dl_server_attach_root: cpu=4 rd_span=0-4 total_bw=262140 > >>> [ 57.496171] CPU5 attaching NULL sched-domain. > >>> [ 57.532952] span=0-4 > >>> [ 57.535143] rq_attach_root: cpu=5 old_span= new_span=0-4 > >>> [ 57.535147] __dl_add: cpus=5 tsk_bw=52428 total_bw=314568 span=0-5 type=DEF > >> > >> Maybe we shouldn't add the dl_server contribution of a CPU that is going > >> to be offline. > > > > I tried to implement this idea and ended up with the following. As usual > > also pushed it to the branch on github. Could you please update and > > re-test? > > > > Another thing that I noticed is that in my case an hotplug operation > > generating a sched/root domain rebuild ends up calling dl_rebuild_ > > rd_accounting() (from partition_and_rebuild_sched_domains()) which > > resets accounting for def and dyn domains. In your case (looking again > > at the last dmesg you shared) I don't see this call, so I wonder if for > > some reason related to your setup we do the rebuild by calling partition_ > > sched_domains() (instead of partition_and_rebuild_) and this doesn't > > call dl_rebuild_rd_accounting() after partition_sched_domains_locked() - > > maybe it should? Dietmar, Christian, Peter, what do you think? > > Yeah, looks like suspend/resume behaves differently compared to CPU hotplug. > > On my Juno [L b b L L L] > ^^^ > isolcpus=[2,3] > > # ps2 | grep DLN > 98 98 S 140 0 - DLN sugov:0 > 99 99 S 140 0 - DLN sugov:1 > > # taskset -p 98; taskset -p 99 > pid 98's current affinity mask: 39 > pid 99's current affinity mask: 6 > > > [ 87.679282] partition_sched_domains() called > ... > [ 87.684013] partition_sched_domains() called > ... > [ 87.687961] partition_sched_domains() called > ... > [ 87.689419] psci: CPU3 killed (polled 0 ms) > [ 87.689715] __dl_bw_capacity() mask=2-5 cap=1024 > [ 87.689739] dl_bw_cpus() cpu=6 rd->span=2-5 cpu_active_mask=0-2 cpus=1 > [ 87.689757] dl_bw_manage: cpu=2 cap=0 fair_server_bw=52428 > total_bw=209712 dl_bw_cpus=1 type=DEF span=2-5 > [ 87.689775] dl_bw_cpus() cpu=6 rd->span=2-5 cpu_active_mask=0-2 cpus=1 > [ 87.689789] dl_bw_manage() cpu=2 cap=0 overflow=1 return=-16 > [ 87.689864] Error taking CPU2 down: -16 <-- !!! > ... > [ 87.690674] partition_sched_domains() called > ... > [ 87.691496] partition_sched_domains() called > ... > [ 87.693702] partition_sched_domains() called > ... > [ 87.695819] partition_and_rebuild_sched_domains() called > Ah, OK. Did you try with my last proposed change?