This issue appears to be an upstream bug. Would it be possible for you to open an upstream bug report[0]? That will allow the upstream Developers to examine the issue, and may provide a quicker resolution to the bug.
Please follow the instructions on the wiki page[0]. The first step is to email the appropriate mailing list. If no response is received, then a bug may be opened on bugzilla.kernel.org. Once this bug is reported upstream, please add the tag: 'kernel-bug- reported-upstream'. [0] https://wiki.ubuntu.com/Bugs/Upstream/kernel ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Status: Confirmed => Triaged -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1591491 Title: On function __update_load_avg issue. Status in linux package in Ubuntu: Triaged Bug description: On this bug need litle explications function embedded __compute_runnable_contrib have at beggining on "big" noop by 100 cycles but why? Looking bellow on contrib is added value but is not used for twice. 2715 /* Efficiently calculate \sum (1..n_period) 1024*y^i */ 2716 contrib = __compute_runnable_contrib(periods); 2717 contrib = cap_scale(contrib, scale_freq); 2718 if (weight) { Look here : http://lxr.free-electrons.com/source/kernel/sched/fair.c#L2716 And content of perf : __compute_runnable_contrib /proc/kcore │ │ │ │ Disassembly of section load0: │ │ ffffffff810b2c70 <load0>: 100,00 │ nop │ cmp $0x20,%rdi │ ↓ ja 13 │ mov -0x7e5e84c0(,%rdi,4),%eax │ ← retq │13: cmp $0x158,%rdi │ ↓ ja 27 │ push %rbp │ mov %rsp,%rbp │ callq 0xffffffff810b2c10 │ pop %rbp │ ← retq │27: mov $0xba7e,%eax │ ← retq ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-22-generic 4.4.0-22.40 ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8 Uname: Linux 4.4.0-22-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/pcmC0D0p: asu 3213 F...m pulseaudio /dev/snd/controlC0: asu 3213 F.... pulseaudio CurrentDesktop: MATE Date: Sat Jun 11 14:17:27 2016 InstallationDate: Installed on 2016-04-29 (42 days ago) InstallationMedia: Ubuntu-Studio 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) IwConfig: lo no wireless extensions. enp1s0 no wireless extensions. MachineType: Olidata S.p.A. ALABAMA ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-22-generic root=/dev/mapper/192--168--0--108--vg-root ro RelatedPackageVersions: linux-restricted-modules-4.4.0-22-generic N/A linux-backports-modules-4.4.0-22-generic N/A linux-firmware 1.157 RfKill: SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/08/2008 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: S0101 dmi.board.asset.tag: To Be Filled By O.E.M. dmi.board.name: To be filled by O.E.M. dmi.board.vendor: To be filled by O.E.M. dmi.board.version: To be filled by O.E.M. dmi.chassis.asset.tag: To Be Filled By O.E.M. dmi.chassis.type: 3 dmi.chassis.vendor: To Be Filled By O.E.M. dmi.chassis.version: To Be Filled By O.E.M. dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrS0101:bd07/08/2008:svnOlidataS.p.A.:pnALABAMA:pvrToBeFilledByO.E.M.:rvnTobefilledbyO.E.M.:rnTobefilledbyO.E.M.:rvrTobefilledbyO.E.M.:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.: dmi.product.name: ALABAMA dmi.product.version: To Be Filled By O.E.M. dmi.sys.vendor: Olidata S.p.A. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1591491/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
