On 2020/07/08 16:22, Richard Ipsum wrote:
> >Synopsis: userland gettimeofday not working?
> >Category: kernel
> >Environment:
> System : OpenBSD 6.7
> Details : OpenBSD 6.7-current (GENERIC.MP) #336: Tue Jul 7
> 22:27:36 MDT 2020
>
> dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
>
> Architecture: OpenBSD.amd64
> Machine : amd64
> >Description:
> gtod.c from https://undeadly.org/cgi?action=article;sid=20200708055508
> still takes ~2 minutes after upgrading to latest snapshot.
> >How-To-Repeat:
> compile gtod.c and invoke as shown in blog post.
user timecounters do not work everywhere, they require invariant TSC
("ITSC" shown in cpu flags), plus they require that the TSCs are in
fairly close sync on the different cores, and that they don't drift
too much.
On your machine there is too much difference between the TSC on
the cpu cores so can't be used as shown by this in your dmesg:
> cpu1: TSC skew=-650 observed drift=0
> cpu1: disabling user TSC (skew=-650)
>
> dmesg:
> OpenBSD 6.7-current (GENERIC.MP) #336: Tue Jul 7 22:27:36 MDT 2020
> dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> real mem = 6210174976 (5922MB)
> avail mem = 6006923264 (5728MB)
> random: good seed from bootblocks
> mpath0 at root
> scsibus0 at mpath0: 256 targets
> mainbus0 at root
> bios0 at mainbus0: SMBIOS rev. 2.6 @ 0xe0010 (78 entries)
> bios0: vendor LENOVO version "6QET62WW (1.32 )" date 12/17/2010
> bios0: LENOVO 3680PDG
> acpi0 at bios0: ACPI 4.0
> acpi0: sleep states S0 S3 S4 S5
> acpi0: tables DSDT FACP SSDT ECDT APIC MCFG HPET ASF! SLIC BOOT SSDT TCPA
> DMAR SSDT SSDT SSDT
> acpi0: wakeup devices LID_(S3) SLPB(S3) IGBE(S4) EXP1(S4) EXP2(S4) EXP3(S4)
> EXP4(S4) EXP5(S4) EHC1(S3) EHC2(S3) HDEF(S4)
> acpitimer0 at acpi0: 3579545 Hz, 24 bits
> acpiec0 at acpi0
> acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat
> cpu0 at mainbus0: apid 0 (boot processor)
> cpu0: Intel(R) Core(TM) i5 CPU M 520 @ 2.40GHz, 2660.48 MHz, 06-25-05
> cpu0:
> FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,POPCNT,AES,NXE,RDTSCP,LONG,LAHF,PERF,ITSC,IBRS,IBPB,STIBP,L1DF,SSBD,SENSOR,ARAT,MELTDOWN
> cpu0: 256KB 64b/line 8-way L2 cache
> cpu0: TSC skew=0 observed drift=0
> cpu0: smt 0, core 0, package 0
> mtrr: Pentium Pro MTRR support, 8 var ranges, 88 fixed ranges
> cpu0: apic clock running at 132MHz
> cpu0: mwait min=64, max=64, C-substates=0.2.1.1, IBE
> cpu1 at mainbus0: apid 4 (application processor)
> cpu1: Intel(R) Core(TM) i5 CPU M 520 @ 2.40GHz, 2660.01 MHz, 06-25-05
> cpu1:
> FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,POPCNT,AES,NXE,RDTSCP,LONG,LAHF,PERF,ITSC,IBRS,IBPB,STIBP,L1DF,SSBD,SENSOR,ARAT,MELTDOWN
> cpu1: 256KB 64b/line 8-way L2 cache
> cpu1: TSC skew=-650 observed drift=0
> cpu1: disabling user TSC (skew=-650)
> cpu1: smt 0, core 2, package 0
> ioapic0 at mainbus0: apid 1 pa 0xfec00000, version 20, 24 pins
> acpimcfg0 at acpi0
> acpimcfg0: addr 0xe0000000, bus 0-255
> acpihpet0 at acpi0: 14318179 Hz
> acpiprt0 at acpi0: bus 0 (PCI0)
> acpiprt1 at acpi0: bus -1 (PEG_)
> acpiprt2 at acpi0: bus 13 (EXP1)
> acpiprt3 at acpi0: bus -1 (EXP2)
> acpiprt4 at acpi0: bus -1 (EXP3)
> acpiprt5 at acpi0: bus 5 (EXP4)
> acpiprt6 at acpi0: bus 2 (EXP5)
> acpicpu0 at acpi0: C3(350@245 mwait.3@0x20), C2(500@205 mwait.3@0x10),
> C1(1000@3 mwait.1), PSS
> acpicpu1 at acpi0: C3(350@245 mwait.3@0x20), C2(500@205 mwait.3@0x10),
> C1(1000@3 mwait.1), PSS
> acpipwrres0 at acpi0: PUBS, resource for EHC1, EHC2
> acpitz0 at acpi0: critical temperature is 100 degC
> acpibtn0 at acpi0: LID_
> acpibtn1 at acpi0: SLPB
> acpipci0 at acpi0 UNCR
> extent `acpipci0 pcibus' (0x0 - 0xff), flags=0
> 0x0 - 0xfe
> extent `pciio' (0x0 - 0xffffffff), flags=0
> 0x10000 - 0xffffffff
> extent `pcimem' (0x0 - 0xffffffffffffffff), flags=0
> 0x0 - 0xbfffffff
> 0xe0000000 - 0xefffffff
> 0xfeaff000 - 0xfeafffff
> 0xfec00000 - 0xfec0ffff
> 0xfed00000 - 0xfed003ff
> 0xfed1c000 - 0xfed8ffff
> 0xfee00000 - 0xfee00fff
> 0xff000000 - 0xffffffff
> 0x40000000000 - 0xffffffffffffffff
> acpipci1 at acpi0 PCI0: 0x00000000 0x00000011 0x00000001
> extent `acpipci1 pcibus' (0x0 - 0xff), flags=0
> 0xff - 0xff
> extent `pciio' (0x0 - 0xffffffff), flags=0
> 0x10000 - 0xffffffff
> extent `pcimem' (0x0 - 0xffffffffffffffff), flags=0
> 0x0 - 0xbfffffff
> 0xe0000000 - 0xefffffff
> 0xfeaff000 - 0xfeafffff
> 0xfec00000 - 0xfec0ffff
> 0xfed00000 - 0xfed003ff
> 0xfed1c000 - 0xfed8ffff
> 0xfee00000 - 0xfee00fff
> 0xff000000 - 0xffffffff
> 0x40000000000 - 0xffffffffffffffff
> acpicmos0 at acpi0
> tpm0 at acpi0 TPM_ addr 0xfed40000/0x5000, device 0x0000104a rev 0x4e
> acpibat0 at acpi0: BAT0 model "42T4694" serial 75 type LION oem "SANYO"
> acpiac0 at acpi0: AC unit online
> acpithinkpad0 at acpi0: version 1.0
> "PNP0C14" at acpi0 not configured
> acpidock0 at acpi0: GDCK not docked (0)
> acpivideo0 at acpi0: VID_
> acpivout0 at acpivideo0: LCD0
> acpivideo1 at acpi0: VID_
> cpu0: using IvyBridge MDS workaround
> cpu0: Enhanced SpeedStep 2660 MHz: speeds: 2400, 2399, 2266, 2133, 1999,
> 1866, 1733, 1599, 1466, 1333, 1199 MHz
> pci0 at mainbus0 bus 255
> pchb0 at pci0 dev 0 function 0 "Intel QuickPath" rev 0x02
> pchb1 at pci0 dev 0 function 1 "Intel QuickPath" rev 0x02
> pchb2 at pci0 dev 2 function 0 "Intel QPI Link" rev 0x02
> pchb3 at pci0 dev 2 function 1 "Intel QPI Physical" rev 0x02
> pchb4 at pci0 dev 2 function 2 "Intel Reserved" rev 0x02
> pchb5 at pci0 dev 2 function 3 "Intel Reserved" rev 0x02
> pci1 at mainbus0 bus 0
> pchb6 at pci1 dev 0 function 0 "Intel Core Host" rev 0x02
> inteldrm0 at pci1 dev 2 function 0 "Intel HD Graphics" rev 0x02
> drm0 at inteldrm0
> intagp0 at inteldrm0
> agp0 at intagp0: aperture at 0xd0000000, size 0x10000000
> inteldrm0: msi, IRONLAKE, gen 5
> "Intel 3400 MEI" rev 0x06 at pci1 dev 22 function 0 not configured
> em0 at pci1 dev 25 function 0 "Intel 82577LM" rev 0x06: msi, address
> f0:de:f1:48:c7:ce
> ehci0 at pci1 dev 26 function 0 "Intel 3400 USB" rev 0x06: apic 1 int 23
> usb0 at ehci0: USB revision 2.0
> uhub0 at usb0 configuration 1 interface 0 "Intel EHCI root hub" rev 2.00/1.00
> addr 1
> azalia0 at pci1 dev 27 function 0 "Intel 3400 HD Audio" rev 0x06: msi
> azalia0: codecs: Conexant/0x5069, Intel/0x2804, using Conexant/0x5069
> audio0 at azalia0
> ppb0 at pci1 dev 28 function 0 "Intel 3400 PCIE" rev 0x06: msi
> pci2 at ppb0 bus 13
> ppb1 at pci1 dev 28 function 3 "Intel 3400 PCIE" rev 0x06: msi
> pci3 at ppb1 bus 5
> ppb2 at pci1 dev 28 function 4 "Intel 3400 PCIE" rev 0x06: msi
> pci4 at ppb2 bus 2
> iwn0 at pci4 dev 0 function 0 "Intel Centrino Advanced-N 6200" rev 0x35: msi,
> MIMO 2T2R, MoW, address 58:94:6b:b3:1f:0c
> ehci1 at pci1 dev 29 function 0 "Intel 3400 USB" rev 0x06: apic 1 int 19
> usb1 at ehci1: USB revision 2.0
> uhub1 at usb1 configuration 1 interface 0 "Intel EHCI root hub" rev 2.00/1.00
> addr 1
> ppb3 at pci1 dev 30 function 0 "Intel 82801BAM Hub-to-PCI" rev 0xa6
> pci5 at ppb3 bus 14
> pcib0 at pci1 dev 31 function 0 "Intel QM57 LPC" rev 0x06
> ahci0 at pci1 dev 31 function 2 "Intel 3400 AHCI" rev 0x06: msi, AHCI 1.3
> ahci0: port 0: 3.0Gb/s
> scsibus1 at ahci0: 32 targets
> sd0 at scsibus1 targ 0 lun 0: <ATA, WDC WD5000LPLX-6, 01.0>
> naa.50014ee65bc6c828
> sd0: 476940MB, 512 bytes/sector, 976773168 sectors
> ichiic0 at pci1 dev 31 function 3 "Intel 3400 SMBus" rev 0x06: apic 1 int 23
> iic0 at ichiic0
> spdmem0 at iic0 addr 0x50: 2GB DDR3 SDRAM PC3-10600 SO-DIMM
> spdmem1 at iic0 addr 0x51: 4GB DDR3 SDRAM PC3-8500 SO-DIMM
> itherm0 at pci1 dev 31 function 6 "Intel 3400 Thermal" rev 0x06
> isa0 at pcib0
> isadma0 at isa0
> pckbc0 at isa0 port 0x60/5 irq 1 irq 12
> pckbd0 at pckbc0 (kbd slot)
> wskbd0 at pckbd0: console keyboard
> pms0 at pckbc0 (aux slot)
> wsmouse0 at pms0 mux 0
> pcppi0 at isa0 port 0x61
> spkr0 at pcppi0
> aps0 at isa0 port 0x1600/31
> vmm0 at mainbus0: VMX/EPT
> uhub2 at uhub0 port 1 configuration 1 interface 0 "Intel Rate Matching Hub"
> rev 2.00/0.00 addr 2
> uvideo0 at uhub2 port 6 configuration 1 interface 0 "Chicony Electronics Co.,
> Ltd. Integrated Camera" rev 2.00/23.45 addr 3
> video0 at uvideo0
> uhub3 at uhub1 port 1 configuration 1 interface 0 "Intel Rate Matching Hub"
> rev 2.00/0.00 addr 2
> vscsi0 at root
> scsibus2 at vscsi0: 256 targets
> softraid0 at root
> scsibus3 at softraid0: 256 targets
> root on sd0a (8f347ed0291c9e12.a) swap on sd0b dump on sd0b
> inteldrm0: 1280x800, 32bpp
> wsdisplay0 at inteldrm0 mux 1: console (std, vt100 emulation), using wskbd0
> wsdisplay0: screen 1-5 added (std, vt100 emulation)
>
> usbdevs:
> Controller /dev/usb0:
> addr 01: 8086:0000 Intel, EHCI root hub
> high speed, self powered, config 1, rev 1.00
> driver: uhub0
> addr 02: 8087:0020 Intel, Rate Matching Hub
> high speed, self powered, config 1, rev 0.00
> driver: uhub2
> addr 03: 17ef:4816 Chicony Electronics Co., Ltd., Integrated Camera
> high speed, power 200 mA, config 1, rev 23.45
> driver: uvideo0
> Controller /dev/usb1:
> addr 01: 8086:0000 Intel, EHCI root hub
> high speed, self powered, config 1, rev 1.00
> driver: uhub1
> addr 02: 8087:0020 Intel, Rate Matching Hub
> high speed, self powered, config 1, rev 0.00
> driver: uhub3
>
