Date: Mon, 21 May 2001 16:32:31 -0700 From: Steve Madsen <madsen@akamba.com> To: "'freebsd-smp@freebsd.org'" <freebsd-smp@freebsd.org> Subject: Supporting old-style SMP in drivers Message-ID: <B5F5C0FDF648D311A9D700508B322DFD3C46A8@mailhost.akamba.com>
next in thread | raw e-mail | index | archive | help
I apologize in advance for the questions, as I know that most discussion
here relates to the new implementation.
I've done several searches and can't seem to find information on the SMP
implementation in 3.x and 4.x. I'm trying to hunt down a bug in a network
driver that only occurs when running on an SMP kernel (4.2, to be exact).
Is there a site or document somewhere that explains the SMP implementation
in 3.x and 4.x?
Is only one CPU ever permitted in the kernel, even when an interrupt fires?
If yes, when will that interrupt be serviced?
Are there any locking primitives that can or should be used for
synchronization?
The problem I'm seeing is that occasionally, the kernel will cease
delivering interrupts to my handler. I can poke the NIC and generate an
interrupt, but the handler is never invoked. I can examine the PCI
registers from a user-space application and see that the interrupt was
generated (and is not masked by the card). It just never gets handled and
cleared.
I did see some vaguely similar problems in the bug database. Here is the
output of "mptable -dmesg -verbose":
============================================================================
===
MPTable, version 2.0.15
looking for EBDA pointer @ 0x040e, found, searching EBDA @ 0x0009f800
searching CMOS 'top of mem' @ 0x0009f400 (637K)
searching default 'top of mem' @ 0x0009fc00 (639K)
searching BIOS @ 0x000f0000
MP FPS found in BIOS @ physical addr: 0x000f72d0
----------------------------------------------------------------------------
---
MP Floating Pointer Structure:
location: BIOS
physical address: 0x000f72d0
signature: '_MP_'
length: 16 bytes
version: 1.1
checksum: 0x41
mode: Virtual Wire
----------------------------------------------------------------------------
---
MP Config Table Header:
physical address: 0x0009f960
signature: 'PCMP'
base table length: 252
version: 1.1
checksum: 0x7c
OEM ID: 'INTEL '
Product ID: 'N440BX '
OEM table pointer: 0x00000000
OEM table size: 0
entry count: 23
local APIC address: 0xfee00000
extended table length: 0
extended table checksum: 0
----------------------------------------------------------------------------
---
MP Config Base Table Entries:
--
Processors: APIC ID Version State Family Model Step
Flags
1 0x11 BSP, usable 6 7 2
0x387fbff
0 0x11 AP, usable 6 7 2
0x387fbff
--
Bus: Bus ID Type
0 PCI
1 ISA
--
I/O APICs: APIC ID Version State Address
2 0x11 usable 0xfec00000
--
I/O Ints: Type Polarity Trigger Bus ID IRQ APIC ID PIN#
ExtINT active-hi edge 1 0 2 0
INT active-hi edge 1 1 2 1
INT active-hi edge 1 0 2 2
INT active-hi edge 1 3 2 3
INT active-hi edge 1 4 2 4
INT active-hi level 1 5 2 5
INT active-hi edge 1 6 2 6
INT active-hi edge 1 7 2 7
INT active-hi edge 1 8 2 8
INT active-hi level 1 9 2 9
INT active-hi level 1 10 2 10
INT active-hi level 1 11 2 11
INT active-hi edge 1 12 2 12
INT active-hi edge 1 13 2 13
INT active-hi edge 1 14 2 14
INT active-hi edge 1 15 2 15
--
Local Ints: Type Polarity Trigger Bus ID IRQ APIC ID PIN#
ExtINT active-hi edge 1 0 255 0
NMI active-hi edge 0 0:A 255 1
----------------------------------------------------------------------------
---
# SMP kernel config file options:
# Required:
options SMP # Symmetric MultiProcessor Kernel
options APIC_IO # Symmetric (APIC) I/O
# Optional (built-in defaults will work in most cases):
#options NCPU=2 # number of CPUs
#options NBUS=2 # number of busses
#options NAPIC=1 # number of IO APICs
#options NINTR=24 # number of INTs
----------------------------------------------------------------------------
---
dmesg output:
Copyright (c) 1992-2000 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
The Regents of the University of California. All rights reserved.
FreeBSD 4.2-RELEASE #34: Mon May 21 16:15:43 PDT 2001
madsen@s18.test.akamba.com:/usr/src/sys/compile/AKAMBA-SMP
Timecounter "i8254" frequency 1193182 Hz
CPU: Pentium III/Pentium III Xeon/Celeron (498.75-MHz 686-class CPU)
Origin = "GenuineIntel" Id = 0x672 Stepping = 2
Features=0x387fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,
CMOV,PAT,PSE36,PN,MMX,FXSR,SSE>
real memory = 536805376 (524224K bytes)
avail memory = 515620864 (503536K bytes)
Programming 24 pins in IOAPIC #0
IOAPIC #0 intpin 2 -> irq 0
FreeBSD/SMP: Multiprocessor motherboard
cpu0 (BSP): apic id: 1, version: 0x00040011, at 0xfee00000
cpu1 (AP): apic id: 0, version: 0x00040011, at 0xfee00000
io0 (APIC): apic id: 2, version: 0x00170011, at 0xfec00000
Preloaded elf kernel "kernel" at 0xc0378000.
Pentium Pro MTRR support enabled
md0: Malloc disk
npx0: <math processor> on motherboard
npx0: INT 16 interface
pcib0: <Intel 82443BX host to PCI bridge (AGP disabled)> on motherboard
pci0: <PCI bus> on pcib0
cb0: <Akamba Velobahn 10/100 Ethernet> mem 0xfa000000-0xfa0fffff irq 11 at
device 11.0 on pci0
cb0: Ethernet address 00:30:76:01:10:8c
cb0: driver is using old-style compatability shims
ncr0: <ncr 53c875 fast20 wide scsi> port 0x1400-0x14ff mem
0xfa200000-0xfa200fff,0xfa203000-0xfa2030ff irq 11 at device 13.0 on pci0
ncr1: <ncr 53c875 fast20 wide scsi> port 0x1800-0x18ff mem
0xfa201000-0xfa201fff,0xfa203400-0xfa2034ff irq 10 at device 13.1 on pci0
fxp0: <Intel Pro 10/100B/100+ Ethernet> port 0x1060-0x107f mem
0xfa100000-0xfa1fffff,0xfa204000-0xfa204fff irq 5 at device 15.0 on pci0
fxp0: Ethernet address 00:a0:c9:ac:fe:94
isab0: <Intel 82371AB PCI to ISA bridge> at device 18.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <Intel PIIX4 ATA33 controller> port 0x1050-0x105f at device 18.1 on
pci0
ata0: at 0x1f0 irq 14 on atapci0
ata1: at 0x170 irq 15 on atapci0
uhci0: <Intel 82371AB/EB (PIIX4) USB controller> port 0x1080-0x109f irq 10
at device 18.2 on pci0
usb0: <Intel 82371AB/EB (PIIX4) USB controller> on uhci0
usb0: USB revision 1.0
uhub0: Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 2 ports with 2 removable, self powered
Timecounter "PIIX" frequency 3579545 Hz
chip1: <Intel 82371AB Power management controller> port 0x1040-0x104f at
device 18.3 on pci0
pci0: <Cirrus Logic GD5480 SVGA controller> at 20.0
fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0
fdc0: FIFO enabled, 8 bytes threshold
fd0: <1440-KB 3.5" drive> on fdc0 drive 0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x100>
sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
sio0: type 16550A, console
sio1 at port 0x2f8-0x2ff irq 3 on isa0
sio1: type 16550A
ppc0: <Parallel port> at port 0x378-0x37f irq 7 on isa0
ppc0: Generic chipset (ECP/PS2/NIBBLE) in COMPATIBLE mode
ppc0: FIFO with 16/16/8 bytes threshold
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
APIC_IO: Testing 8254 interrupt delivery
APIC_IO: routing 8254 via IOAPIC #0 intpin 2
cb0 XXX: driver didn't set ifq_maxlen
SMP: AP CPU #1 Launched!
ad0: 9641MB <IBM-DTTA-371010> [19590/16/63] at ata0-master UDMA33
Mounting root from ufs:/dev/ad0s1a
cb0: not multicast capable, IPv6 not enabled
============================================================================
===
--
Steve Madsen <madsen@akamba.com>
Akamba Corporation, http://www.akamba.com
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-smp" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?B5F5C0FDF648D311A9D700508B322DFD3C46A8>