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cxgb3 - notify iWARP of chip resets

PATCH Applied Divy Le Ray 6 participants 8 messages Jan 26, 2009 – Jan 27, 2009

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Divy Le Ray

author
#0 lore raw

cover cxgb3 - notify iWARP of chip resets

Hi Dave, Roland,

I'm submitting 2 patches against cxgb3 and iw_cxgb3 respectively. They are built against net-next-2.6.
The first patch adds a notification mechanism to cxgb3 to alert the upper layer drivers (iWARP and iSCSI) of a chip reset.

The second patch adds the handler for such an event in the iWARP driver.

Since the second patch depends on the first one, I submit them together, even though the second patch should be submitted against Roland's tree.

Cheers,
Divy

#1 lore raw
Quoted 9 lines

I'm submitting 2 patches against cxgb3 and iw_cxgb3 respectively. They are built against net-next-2.6.
The first patch adds a notification mechanism to cxgb3 to alert the upper layer drivers (iWARP and iSCSI) of a chip reset.

The second patch adds the handler for such an event in the iWARP driver.

Since the second patch depends on the first one, I submit them together, even though the second patch should be submitted against Roland's tree.

simplest thing is for Dave to merge both, and I'm fine with that.

- R.

maintainer
#2 lore raw

From: Roland Dreier <[email protected]>
Date: Mon, 26 Jan 2009 09:57:54 -0800

Quoted 11 lines
Quoted 9 lines

I'm submitting 2 patches against cxgb3 and iw_cxgb3 respectively. They are built against net-next-2.6.
The first patch adds a notification mechanism to cxgb3 to alert the upper layer drivers (iWARP and iSCSI) of a chip reset.

The second patch adds the handler for such an event in the iWARP driver.

Since the second patch depends on the first one, I submit them together, even though the second patch should be submitted against Roland's tree.

simplest thing is for Dave to merge both, and I'm fine with that.

Ok, I'll take care of this.

#3 lore raw

DCA/IOAT problem

In reply to Divy Le Ray

Hello

Some lspci:
lspci
00:00.0 Host bridge: Intel Corporation Memory Controller Hub (rev 90)
00:02.0 PCI bridge: Intel Corporation PCI Express x8 Port 2-3 (rev 90)
00:04.0 PCI bridge: Intel Corporation PCI Express x16 Port 4-7 (rev 90)
00:08.0 System peripheral: Intel Corporation DMA Engine (rev 90)
00:10.0 Host bridge: Intel Corporation FSB Registers (rev 90)
00:10.1 Host bridge: Intel Corporation FSB Registers (rev 90)
00:10.2 Host bridge: Intel Corporation FSB Registers (rev 90)
00:11.0 Host bridge: Intel Corporation Reserved Registers (rev 90)
00:13.0 Host bridge: Intel Corporation Reserved Registers (rev 90)
00:15.0 Host bridge: Intel Corporation DDR Channel 0 Registers (rev 90)
00:16.0 Host bridge: Intel Corporation DDR Channel 1 Registers (rev 90)
00:1a.0 USB Controller: Intel Corporation USB UHCI Controller #4 (rev 02)
00:1a.7 USB Controller: Intel Corporation USB2 EHCI Controller #2 (rev 02)
00:1c.0 PCI bridge: Intel Corporation PCI Express Port 1 (rev 02)
00:1c.4 PCI bridge: Intel Corporation PCI Express Port 5 (rev 02)
00:1c.5 PCI bridge: Intel Corporation PCI Express Port 6 (rev 02)
00:1d.0 USB Controller: Intel Corporation USB UHCI Controller #1 (rev 02)
00:1d.1 USB Controller: Intel Corporation USB UHCI Controller #2 (rev 02)
00:1d.2 USB Controller: Intel Corporation USB UHCI Controller #3 (rev 02)
00:1d.7 USB Controller: Intel Corporation USB2 EHCI Controller #1 (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 92)
00:1f.0 ISA bridge: Intel Corporation LPC Interface Controller (rev 02)
00:1f.2 IDE interface: Intel Corporation 4 port SATA IDE Controller (rev 02) 00:1f.3 SMBus: Intel Corporation SMBus Controller (rev 02)
00:1f.5 IDE interface: Intel Corporation 2 port SATA IDE Controller (rev 02) 01:00.0 Ethernet controller: Intel Corporation Device 10dd (rev 01)
04:00.0 Ethernet controller: Intel Corporation 82573E Gigabit Ethernet Controller (Copper) (rev 03) 05:00.0 Ethernet controller: Intel Corporation 82573L Gigabit Ethernet Controller 06:01.0 VGA compatible controller: ATI Technologies Inc ES1000 (rev 02)

and then:
modprobe ioatdma

dmesg:
...
...
IPv4 FIB: Using LC-trie version 0.408
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X
e1000e 0000:05:00.0: irq 1273 for MSI/MSI-X
e1000e 0000:05:00.0: irq 1273 for MSI/MSI-X
0000:05:00.0: eth1: Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
dca service started, version 1.4
ioatdma 0000:00:08.0: can't find IRQ for PCI INT A; probably buggy MP table
ioatdma 0000:00:08.0: setting latency timer to 64
ioatdma 0000:00:08.0: Intel(R) I/OAT DMA Engine found, 4 channels, device version 0x12, driver version 3.30 ioatdma 0000:00:08.0: irq 1255 for MSI/MSI-X
ioatdma 0000:00:08.0: DCA is disabled in BIOS
ixgbe: eth2: ixgbe_watchdog_task: NIC Link is Up 10 Gbps, Flow Control: None
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X

...
...

lspvi -vvv (for dma engine)
00:08.0 System peripheral: Intel Corporation DMA Engine (rev 90)
Subsystem: Super Micro Computer Inc Device de80
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
<TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0
Interrupt: pin A routed to IRQ 1255
Region 0: Memory at fe700000 (64-bit, non-prefetchable) [size=1K]
Capabilities: [50] Power Management version 2
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
PME(D0+,D1-,D2-,D3hot+,D3cold+)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [58] Message Signalled Interrupts: Mask- 64bit-
Queue=0/0 Enable+
Address: feeff00c Data: 41b2
Capabilities: [6c] Express (v1) Root Complex Integrated
Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s
<64ns, L1 <1us
ExtTag- RBE- FLReset-
DevCtl: Report errors: Correctable- Non-Fatal- Fatal+
Unsupported-
RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop+ MaxPayload 128 bytes, MaxReadReq 128 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr-
TransPend-
LnkCap: Port #0, Speed unknown, Width x0, ASPM unknown,
Latency L0 <64ns, L1 <1us
ClockPM- Suprise- LLActRep- BwNot-
LnkCtl: ASPM Disabled; Disabled- Retrain- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed unknown, Width x0, TrErr- Train- SlotClk-
DLActive- BWMgmt- ABWMgmt-
Kernel driver in use: ioatdma

cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3 CPU4
CPU5 CPU6 CPU7
0: 81 6 9 7 5
3 9 5 IO-APIC-edge timer
1: 1 0 0 0 1
0 0 0 IO-APIC-edge i8042
2: 0 0 0 0 0

0          0          0    XT-PIC-XT        cascade
14:        901        857        867        864        708        674        693        692   IO-APIC-edge      ata_piix
15:        686        728        691        703        826        897        876        872   IO-APIC-edge      ata_piix
18:          0          0          0          0          0          0          0          0   IO-APIC-fasteoi   ata_piix
1255:          1          0          1          0          1          0          1          1   PCI-MSI-edge      ioat-msi
1256:          0          0          0          0          0          0          0          0   PCI-MSI-edge      eth2:lsc
1257:        857        720       1176        802        960        751        706        841   PCI-MSI-edge      eth2:v15-Tx
1258:        958        751        706        841       1176        802        720        859   PCI-MSI-edge      eth2:v14-Tx
1259:       1176        802        720        859        706        841        751        958   PCI-MSI-edge      eth2:v13-Tx
1260:        706        842        751        959        720        858        802       1175   PCI-MSI-edge      eth2:v12-Tx
1261:        720        858        802       1174        751        960        842        706   PCI-MSI-edge      eth2:v11-Tx
1262:        751        960        842        706        802       1174        858        720   PCI-MSI-edge      eth2:v10-Tx
1263:        802       1174        858        720        842        706        960        751   PCI-MSI-edge      eth2:v9-Tx
1264:        842        707        960        751        859        719       1173        802   PCI-MSI-edge      eth2:v8-Tx
1265:     814186     813591     813713     814872     814537     816002     812892     814292   PCI-MSI-edge      eth2:v7-Rx
1266:     626856     626688     627886     627507     628067     625730     626561     626521   PCI-MSI-edge      eth2:v6-Rx
1267:     592474     591312     591741     592107     592214     593218     591271     591386   PCI-MSI-edge      eth2:v5-Rx
1268:     558076     559008     557856     558677     557894     556703     557997     558879   PCI-MSI-edge      eth2:v4-Rx
1269:     723457     725019     723746     724688     723165     724716     724037     725136   PCI-MSI-edge      eth2:v3-Rx
1270:     553387     554096     553204     552603     553078     553587     553838     553769   PCI-MSI-edge      eth2:v2-Rx
1271:     603820     605323     605368     602989     604948     604887     606911     604745   PCI-MSI-edge      eth2:v1-Rx
1272:     800828     798049     799471     799703     799183     798322     799220     798254   PCI-MSI-edge      eth2:v0-Rx
1273:       2868       2894       2970       2808       2863       2803       3167       2860   PCI-MSI-edge      eth1
1274:        873        856        882        924        933        904        864        943   PCI-MSI-edge      eth0
NMI:          0          0          0          0          0          0          0          0   Non-maskable interrupts
LOC:      40527      41783      40049      40903      42180      39477      49021      47628   Local timer interrupts
RES:        858         58        232        283         89         97        284        435   Rescheduling interrupts
CAL:         52        101         99         88         96         93         92         58   Function call interrupts
TLB:        143        133        486        452        141        159        396        429   TLB shootdowns
SPU:          0          0          0          0          0          0          0          0   Spurious interrupts
ERR:          0
MIS:          0

cat /proc/cpuinfo
cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 5999.79
clflush size : 64
power management:

processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 0
cpu cores : 4
apicid : 4
initial apicid : 4
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 6065.40
clflush size : 64
power management:

processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 4
apicid : 1
initial apicid : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 6000.46
clflush size : 64
power management:

processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 1
cpu cores : 4
apicid : 5
initial apicid : 5
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 6000.47
clflush size : 64
power management:

processor : 4
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 2
cpu cores : 4
apicid : 2
initial apicid : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 6000.43
clflush size : 64
power management:

processor : 5
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 2
cpu cores : 4
apicid : 6
initial apicid : 6
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 6000.50
clflush size : 64
power management:

processor : 6
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 3
initial apicid : 3
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 6000.43
clflush size : 64
power management:

processor : 7
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 3
cpu cores : 4
apicid : 7
initial apicid : 7
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi flexpriority
bogomips : 6000.47
clflush size : 64
power management:

I have enabled DCA in my Bios.
So why i have info:
ioatdma 0000:00:08.0: DCA is disabled in BIOS

and:
ls -la /sys/class/dca/
total 0
drwxr-xr-x 2 root root 0 Jan 26 16:21 .
drwxr-xr-x 33 root root 0 Jan 26 16:14 ..

cat /sys/class/dma/dma0chan0/in_use
0
cat /sys/class/dma/dma0chan1/in_use
1
cat /sys/class/dma/dma0chan2/in_use
0
cat /sys/class/dma/dma0chan3/in_use
0

Why DCA is not working (or workink but no info about in ioat)

#4 lore raw

Re: DCA/IOAT problem

Quoted 3 lines · Paweł Staszewski

ioatdma 0000:00:08.0: DCA is disabled in BIOS

Why DCA is not working (or workink but no info about in ioat)

See above in dmesg: It's disabled in BIOS. If the BIOS doesn't have an option to enable DCA, you need to talk to your vendor. Or you can try changing registers on the chipset manually...

Brice

#5 lore raw

Re: [ SPAM ] Re: DCA/IOAT problem

Brice Goglin pisze:

Quoted 11 lines
Quoted 4 lines · Paweł Staszewski

ioatdma 0000:00:08.0: DCA is disabled in BIOS

Why DCA is not working (or workink but no info about in ioat)

See above in dmesg: It's disabled in BIOS. If the BIOS doesn't have an option to enable DCA, you need to talk to your vendor. Or you can try changing registers on the chipset manually...

Quoted 9 lines

Brice

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yes ok.
but in bios i have an option to enable DCA and i make it. (so DCA is enabled in bios )

thats why i ask question why is not enabled :)

So i think only changing registers may help ...

Thanks for reply.

#6 lore raw

RE: DCA/IOAT problem

In reply to Paweł Staszewski

Forwarding entire message to include e1000-devel

Quoted 417 lines · Pawel Staszewski

Hello

Some lspci:
lspci
00:00.0 Host bridge: Intel Corporation Memory Controller Hub (rev 90) 00:02.0 PCI bridge: Intel Corporation PCI Express x8 Port 2-3 (rev 90) 00:04.0 PCI bridge: Intel Corporation PCI Express x16 Port 4-7 (rev
90) 00:08.0 System peripheral: Intel Corporation DMA Engine (rev 90) 00:10.0 Host bridge: Intel Corporation FSB Registers (rev 90) 00:10.1 Host bridge: Intel Corporation FSB Registers (rev 90) 00:10.2 Host bridge: Intel Corporation FSB Registers (rev 90) 00:11.0 Host bridge: Intel Corporation Reserved Registers (rev 90) 00:13.0 Host bridge: Intel Corporation Reserved Registers (rev 90) 00:15.0 Host bridge: Intel Corporation DDR Channel 0 Registers (rev
90) 00:16.0 Host bridge: Intel Corporation DDR Channel 1 Registers (rev 90) 00:1a.0 USB Controller: Intel Corporation USB UHCI Controller #4 (rev 02) 00:1a.7 USB Controller: Intel Corporation USB2 EHCI Controller #2 (rev 02) 00:1c.0 PCI bridge: Intel Corporation PCI Express Port 1 (rev 02) 00:1c.4 PCI bridge: Intel Corporation PCI Express Port 5 (rev 02) 00:1c.5 PCI bridge: Intel Corporation PCI Express Port 6 (rev 02) 00:1d.0 USB Controller: Intel Corporation USB UHCI Controller #1 (rev 02) 00:1d.1 USB Controller: Intel Corporation USB UHCI Controller #2 (rev 02) 00:1d.2 USB Controller: Intel Corporation USB UHCI Controller #3 (rev 02) 00:1d.7 USB Controller:
Intel Corporation USB2 EHCI Controller #1 (rev 02) 00:1e.0 PCI
bridge: Intel Corporation 82801 PCI Bridge (rev 92) 00:1f.0 ISA
bridge: Intel Corporation LPC Interface Controller (rev 02) 00:1f.2 IDE interface: Intel Corporation 4 port SATA IDE Controller (rev 02) 00:1f.3 SMBus: Intel Corporation SMBus Controller (rev 02) 00:1f.5 IDE interface: Intel Corporation 2 port SATA IDE Controller (rev 02) 01:00.0 Ethernet controller: Intel Corporation Device 10dd (rev 01) 04:00.0 Ethernet controller: Intel Corporation 82573E Gigabit Ethernet Controller (Copper) (rev 03) 05:00.0 Ethernet controller:
Intel Corporation 82573L Gigabit Ethernet Controller 06:01.0 VGA compatible controller: ATI Technologies Inc ES1000 (rev
02)
and then:
modprobe ioatdma

dmesg:
...
...
IPv4 FIB: Using LC-trie version 0.408
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X
e1000e 0000:05:00.0: irq 1273 for MSI/MSI-X
e1000e 0000:05:00.0: irq 1273 for MSI/MSI-X
0000:05:00.0: eth1: Link is Up 1000 Mbps Full Duplex, Flow Control:
RX/TX dca service started, version 1.4
ioatdma 0000:00:08.0: can't find IRQ for PCI INT A; probably buggy MP table ioatdma 0000:00:08.0: setting latency timer to 64 ioatdma 0000:00:08.0: Intel(R) I/OAT DMA Engine found, 4 channels, device version 0x12, driver version 3.30
ioatdma 0000:00:08.0: irq 1255 for MSI/MSI-X
ioatdma 0000:00:08.0: DCA is disabled in BIOS
ixgbe: eth2: ixgbe_watchdog_task: NIC Link is Up 10 Gbps, Flow
Control: None e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X

...
...

lspvi -vvv (for dma engine)
00:08.0 System peripheral: Intel Corporation DMA Engine (rev 90)
Subsystem: Super Micro Computer Inc Device de80
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
<TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0
Interrupt: pin A routed to IRQ 1255
Region 0: Memory at fe700000 (64-bit, non-prefetchable) [size=1K] Capabilities: [50] Power Management version 2
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
PME(D0+,D1-,D2-,D3hot+,D3cold+)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [58] Message Signalled Interrupts: Mask- 64bit-
Queue=0/0 Enable+
Address: feeff00c Data: 41b2
Capabilities: [6c] Express (v1) Root Complex Integrated
Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s
<64ns, L1 <1us
ExtTag- RBE- FLReset-
DevCtl: Report errors: Correctable- Non-Fatal- Fatal+
Unsupported-
RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop+ MaxPayload 128 bytes, MaxReadReq 128 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq-
AuxPwr- TransPend-
LnkCap: Port #0, Speed unknown, Width x0, ASPM
unknown, Latency L0 <64ns, L1 <1us
ClockPM- Suprise- LLActRep- BwNot-
LnkCtl: ASPM Disabled; Disabled- Retrain- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed unknown, Width x0, TrErr- Train-
SlotClk- DLActive- BWMgmt- ABWMgmt-
Kernel driver in use: ioatdma

cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3 CPU4
CPU5 CPU6 CPU7
0: 81 6 9 7 5
3 9 5 IO-APIC-edge timer
1: 1 0 0 0 1
0 0 0 IO-APIC-edge i8042
2: 0 0 0 0 0
0 0 0 XT-PIC-XT cascade
14: 901 857 867 864 708
674 693 692 IO-APIC-edge ata_piix
15: 686 728 691 703 826
897 876 872 IO-APIC-edge ata_piix
18: 0 0 0 0 0

0          0          0   IO-APIC-fasteoi   ata_piix
1255:          1          0          1          0          1
0          1          1   PCI-MSI-edge      ioat-msi
1256:          0          0          0          0          0
0          0          0   PCI-MSI-edge      eth2:lsc
1257:        857        720       1176        802        960
751        706        841   PCI-MSI-edge      eth2:v15-Tx
1258:        958        751        706        841       1176
802        720        859   PCI-MSI-edge      eth2:v14-Tx
1259:       1176        802        720        859        706
841        751        958   PCI-MSI-edge      eth2:v13-Tx
1260:        706        842        751        959        720
858        802       1175   PCI-MSI-edge      eth2:v12-Tx

1261: 720 858 802 1174 751
960 842 706 PCI-MSI-edge eth2:v11-Tx
1262: 751 960 842 706 802
1174 858 720 PCI-MSI-edge eth2:v10-Tx

1263:        802       1174        858        720        842
706        960        751   PCI-MSI-edge      eth2:v9-Tx
1264:        842        707        960        751        859
719       1173        802   PCI-MSI-edge      eth2:v8-Tx

1265: 814186 813591 813713 814872 814537
816002 812892 814292 PCI-MSI-edge eth2:v7-Rx
1266: 626856 626688 627886 627507 628067
625730 626561 626521 PCI-MSI-edge eth2:v6-Rx
1267: 592474 591312 591741 592107 592214
593218 591271 591386 PCI-MSI-edge eth2:v5-Rx
1268: 558076 559008 557856 558677 557894
556703 557997 558879 PCI-MSI-edge eth2:v4-Rx
1269: 723457 725019 723746 724688 723165
724716 724037 725136 PCI-MSI-edge eth2:v3-Rx
1270: 553387 554096 553204 552603 553078
553587 553838 553769 PCI-MSI-edge eth2:v2-Rx
1271: 603820 605323 605368 602989 604948
604887 606911 604745 PCI-MSI-edge eth2:v1-Rx
1272: 800828 798049 799471 799703 799183
798322 799220 798254 PCI-MSI-edge eth2:v0-Rx
1273: 2868 2894 2970 2808 2863
2803 3167 2860 PCI-MSI-edge eth1
1274: 873 856 882 924 933
904 864 943 PCI-MSI-edge eth0
NMI: 0 0 0 0 0
0 0 0 Non-maskable interrupts
LOC: 40527 41783 40049 40903 42180
39477 49021 47628 Local timer interrupts
RES: 858 58 232 283 89
97 284 435 Rescheduling interrupts
CAL: 52 101 99 88 96
93 92 58 Function call interrupts
TLB: 143 133 486 452 141
159 396 429 TLB shootdowns
SPU: 0 0 0 0 0
0 0 0 Spurious interrupts

ERR:          0
MIS:          0

cat /proc/cpuinfo
cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 5999.79
clflush size : 64
power management:

processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 0
cpu cores : 4
apicid : 4
initial apicid : 4
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6065.40
clflush size : 64
power management:

processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 4
apicid : 1
initial apicid : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.46
clflush size : 64
power management:

processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 1
cpu cores : 4
apicid : 5
initial apicid : 5
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.47
clflush size : 64
power management:

processor : 4
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 2
cpu cores : 4
apicid : 2
initial apicid : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.43
clflush size : 64
power management:

processor : 5
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 2
cpu cores : 4
apicid : 6
initial apicid : 6
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.50
clflush size : 64
power management:

processor : 6
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 3
initial apicid : 3
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.43
clflush size : 64
power management:

processor : 7
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 3
cpu cores : 4
apicid : 7
initial apicid : 7
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.47
clflush size : 64
power management:

Quoted 3 lines

I have enabled DCA in my Bios.
So why i have info:
ioatdma 0000:00:08.0: DCA is disabled in BIOS

Probably because the BIOS is not working correctly or there is a bug in dca. Is that a supermicro machine? Can you include the output of dmidecode? Are you running the latest BIOS? What are you trying to achieve? DCA or IOAT DMA copy offload (two separate features)

Quoted 17 lines

and:
ls -la /sys/class/dca/
total 0
drwxr-xr-x 2 root root 0 Jan 26 16:21 .
drwxr-xr-x 33 root root 0 Jan 26 16:14 ..

cat /sys/class/dma/dma0chan0/in_use
0
cat /sys/class/dma/dma0chan1/in_use
1
cat /sys/class/dma/dma0chan2/in_use
0
cat /sys/class/dma/dma0chan3/in_use
0

Quoted 1 line

Why DCA is not working (or working but no info about in ioat)

The DMA channels (copy offload) are different than the DCA feature. DCA involves front side bus hints sent from the adapter to the CPU handling the interrupt, where DMA channels are for copy offload from the processor to the independent data movers (DMA channels)

#7 lore raw

Re: DCA/IOAT problem

Brandeburg, Jesse pisze:

Quoted 421 lines

Forwarding entire message to include e1000-devel

Quoted 417 lines · Pawel Staszewski

Hello

Some lspci:
lspci
00:00.0 Host bridge: Intel Corporation Memory Controller Hub (rev 90) 00:02.0 PCI bridge: Intel Corporation PCI Express x8 Port 2-3 (rev 90) 00:04.0 PCI bridge: Intel Corporation PCI Express x16 Port 4-7 (rev
90) 00:08.0 System peripheral: Intel Corporation DMA Engine (rev 90) 00:10.0 Host bridge: Intel Corporation FSB Registers (rev 90) 00:10.1 Host bridge: Intel Corporation FSB Registers (rev 90) 00:10.2 Host bridge: Intel Corporation FSB Registers (rev 90) 00:11.0 Host bridge: Intel Corporation Reserved Registers (rev 90) 00:13.0 Host bridge: Intel Corporation Reserved Registers (rev 90) 00:15.0 Host bridge: Intel Corporation DDR Channel 0 Registers (rev
90) 00:16.0 Host bridge: Intel Corporation DDR Channel 1 Registers (rev 90) 00:1a.0 USB Controller: Intel Corporation USB UHCI Controller #4 (rev 02) 00:1a.7 USB Controller: Intel Corporation USB2 EHCI Controller #2 (rev 02) 00:1c.0 PCI bridge: Intel Corporation PCI Express Port 1 (rev 02) 00:1c.4 PCI bridge: Intel Corporation PCI Express Port 5 (rev 02) 00:1c.5 PCI bridge: Intel Corporation PCI Express Port 6 (rev 02) 00:1d.0 USB Controller: Intel Corporation USB UHCI Controller #1 (rev 02) 00:1d.1 USB Controller: Intel Corporation USB UHCI Controller #2 (rev 02) 00:1d.2 USB Controller: Intel Corporation USB UHCI Controller #3 (rev 02) 00:1d.7 USB Controller:
Intel Corporation USB2 EHCI Controller #1 (rev 02) 00:1e.0 PCI
bridge: Intel Corporation 82801 PCI Bridge (rev 92) 00:1f.0 ISA
bridge: Intel Corporation LPC Interface Controller (rev 02) 00:1f.2 IDE interface: Intel Corporation 4 port SATA IDE Controller (rev 02) 00:1f.3 SMBus: Intel Corporation SMBus Controller (rev 02) 00:1f.5 IDE interface: Intel Corporation 2 port SATA IDE Controller (rev 02) 01:00.0 Ethernet controller: Intel Corporation Device 10dd (rev 01) 04:00.0 Ethernet controller: Intel Corporation 82573E Gigabit Ethernet Controller (Copper) (rev 03) 05:00.0 Ethernet controller:
Intel Corporation 82573L Gigabit Ethernet Controller 06:01.0 VGA compatible controller: ATI Technologies Inc ES1000 (rev
02)
and then:
modprobe ioatdma

dmesg:
...
...
IPv4 FIB: Using LC-trie version 0.408
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X
e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X
e1000e 0000:05:00.0: irq 1273 for MSI/MSI-X
e1000e 0000:05:00.0: irq 1273 for MSI/MSI-X
0000:05:00.0: eth1: Link is Up 1000 Mbps Full Duplex, Flow Control:
RX/TX dca service started, version 1.4
ioatdma 0000:00:08.0: can't find IRQ for PCI INT A; probably buggy MP table ioatdma 0000:00:08.0: setting latency timer to 64 ioatdma 0000:00:08.0: Intel(R) I/OAT DMA Engine found, 4 channels, device version 0x12, driver version 3.30
ioatdma 0000:00:08.0: irq 1255 for MSI/MSI-X
ioatdma 0000:00:08.0: DCA is disabled in BIOS
ixgbe: eth2: ixgbe_watchdog_task: NIC Link is Up 10 Gbps, Flow
Control: None e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X e1000e 0000:04:00.0: irq 1274 for MSI/MSI-X

...
...

lspvi -vvv (for dma engine)
00:08.0 System peripheral: Intel Corporation DMA Engine (rev 90)
Subsystem: Super Micro Computer Inc Device de80
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
<TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0
Interrupt: pin A routed to IRQ 1255
Region 0: Memory at fe700000 (64-bit, non-prefetchable) [size=1K] Capabilities: [50] Power Management version 2
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
PME(D0+,D1-,D2-,D3hot+,D3cold+)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [58] Message Signalled Interrupts: Mask- 64bit-
Queue=0/0 Enable+
Address: feeff00c Data: 41b2
Capabilities: [6c] Express (v1) Root Complex Integrated
Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s
<64ns, L1 <1us
ExtTag- RBE- FLReset-
DevCtl: Report errors: Correctable- Non-Fatal- Fatal+
Unsupported-
RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop+ MaxPayload 128 bytes, MaxReadReq 128 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq-
AuxPwr- TransPend-
LnkCap: Port #0, Speed unknown, Width x0, ASPM
unknown, Latency L0 <64ns, L1 <1us
ClockPM- Suprise- LLActRep- BwNot-
LnkCtl: ASPM Disabled; Disabled- Retrain- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed unknown, Width x0, TrErr- Train-
SlotClk- DLActive- BWMgmt- ABWMgmt-
Kernel driver in use: ioatdma

cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3 CPU4
CPU5 CPU6 CPU7
0: 81 6 9 7 5
3 9 5 IO-APIC-edge timer
1: 1 0 0 0 1
0 0 0 IO-APIC-edge i8042
2: 0 0 0 0 0
0 0 0 XT-PIC-XT cascade
14: 901 857 867 864 708
674 693 692 IO-APIC-edge ata_piix
15: 686 728 691 703 826
897 876 872 IO-APIC-edge ata_piix
18: 0 0 0 0 0

0          0          0   IO-APIC-fasteoi   ata_piix
1255:          1          0          1          0          1
0          1          1   PCI-MSI-edge      ioat-msi
1256:          0          0          0          0          0
0          0          0   PCI-MSI-edge      eth2:lsc
1257:        857        720       1176        802        960
751        706        841   PCI-MSI-edge      eth2:v15-Tx
1258:        958        751        706        841       1176
802        720        859   PCI-MSI-edge      eth2:v14-Tx
1259:       1176        802        720        859        706
841        751        958   PCI-MSI-edge      eth2:v13-Tx
1260:        706        842        751        959        720
858        802       1175   PCI-MSI-edge      eth2:v12-Tx

1261: 720 858 802 1174 751
960 842 706 PCI-MSI-edge eth2:v11-Tx
1262: 751 960 842 706 802
1174 858 720 PCI-MSI-edge eth2:v10-Tx

1263:        802       1174        858        720        842
706        960        751   PCI-MSI-edge      eth2:v9-Tx
1264:        842        707        960        751        859
719       1173        802   PCI-MSI-edge      eth2:v8-Tx

1265: 814186 813591 813713 814872 814537
816002 812892 814292 PCI-MSI-edge eth2:v7-Rx
1266: 626856 626688 627886 627507 628067
625730 626561 626521 PCI-MSI-edge eth2:v6-Rx
1267: 592474 591312 591741 592107 592214
593218 591271 591386 PCI-MSI-edge eth2:v5-Rx
1268: 558076 559008 557856 558677 557894
556703 557997 558879 PCI-MSI-edge eth2:v4-Rx
1269: 723457 725019 723746 724688 723165
724716 724037 725136 PCI-MSI-edge eth2:v3-Rx
1270: 553387 554096 553204 552603 553078
553587 553838 553769 PCI-MSI-edge eth2:v2-Rx
1271: 603820 605323 605368 602989 604948
604887 606911 604745 PCI-MSI-edge eth2:v1-Rx
1272: 800828 798049 799471 799703 799183
798322 799220 798254 PCI-MSI-edge eth2:v0-Rx
1273: 2868 2894 2970 2808 2863
2803 3167 2860 PCI-MSI-edge eth1
1274: 873 856 882 924 933
904 864 943 PCI-MSI-edge eth0
NMI: 0 0 0 0 0
0 0 0 Non-maskable interrupts
LOC: 40527 41783 40049 40903 42180
39477 49021 47628 Local timer interrupts
RES: 858 58 232 283 89
97 284 435 Rescheduling interrupts
CAL: 52 101 99 88 96
93 92 58 Function call interrupts
TLB: 143 133 486 452 141
159 396 429 TLB shootdowns
SPU: 0 0 0 0 0
0 0 0 Spurious interrupts

ERR:          0
MIS:          0

cat /proc/cpuinfo
cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 5999.79
clflush size : 64
power management:

processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 0
cpu cores : 4
apicid : 4
initial apicid : 4
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6065.40
clflush size : 64
power management:

processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 4
apicid : 1
initial apicid : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.46
clflush size : 64
power management:

processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 1
cpu cores : 4
apicid : 5
initial apicid : 5
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.47
clflush size : 64
power management:

processor : 4
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 2
cpu cores : 4
apicid : 2
initial apicid : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.43
clflush size : 64
power management:

processor : 5
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 2
cpu cores : 4
apicid : 6
initial apicid : 6
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.50
clflush size : 64
power management:

processor : 6
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 3
initial apicid : 3
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.43
clflush size : 64
power management:

processor : 7
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU X5450 @ 3.00GHz
stepping : 6
cpu MHz : 2999.898
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 3
cpu cores : 4
apicid : 7
initial apicid : 7
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 lahf_lm tpr_shadow vnmi
flexpriority bogomips : 6000.47
clflush size : 64
power management:

Quoted 8 lines
Quoted 4 lines

I have enabled DCA in my Bios.
So why i have info:
ioatdma 0000:00:08.0: DCA is disabled in BIOS

Probably because the BIOS is not working correctly or there is a bug in dca. Is that a supermicro machine? Can you include the output of dmidecode? Are you running the latest BIOS? What are you trying to achieve? DCA or IOAT DMA copy offload (two separate features)

Yes this is an supermicro board X7DCT-10G
http://www.supermicro.com/products/motherboard/Xeon1333/5100/X7DCT-10G.cfm
Bios is no latest but in new bios is no info in changelog about ioat/dca so i don't update i want to test / compare DCA over IOAT with my env that is Traffic management Linux sever with more than 3Gbit/s traffic and 10k users.

dmidecode:

# dmidecode 2.9
SMBIOS 2.5 present.
39 structures occupying 1950 bytes.
Table at 0xDFF5F000.

Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
Vendor: Phoenix Technologies LTD
Version: 1.0c
Release Date: 07/10/2008
Address: 0xE5100
Runtime Size: 110336 bytes
ROM Size: 2048 kB
Characteristics:
ISA is supported
PCI is supported
PNP is supported
BIOS is upgradeable
BIOS shadowing is allowed
ESCD support is available
Boot from CD is supported
Selectable boot is supported
BIOS ROM is socketed
EDD is supported
5.25"/1.2 MB floppy services are supported (int 13h) 3.5"/720 KB floppy services are supported (int 13h) 3.5"/2.88 MB floppy services are supported (int 13h) Print screen service is supported (int 5h) 8042 keyboard services are supported (int 9h) Serial services are supported (int 14h) Printer services are supported (int 17h) CGA/mono video services are supported (int 10h) ACPI is supported
USB legacy is supported
BIOS boot specification is supported Targeted content distribution is supported

Handle 0x0001, DMI type 1, 27 bytes
System Information
Manufacturer: Supermicro
Product Name: X7DCT
Version: 0123456789
Serial Number: 0123456789
UUID: E3D0A497-4663-90E7-895F-003048D333D7
Wake-up Type: Power Switch
SKU Number: Not Specified
Family: Not Specified

Handle 0x0002, DMI type 2, 10 bytes
Base Board Information
Manufacturer: Supermicro
Product Name: X7DCT
Version: PCB Version
Serial Number: 0123456789

Handle 0x0003, DMI type 3, 17 bytes
Chassis Information
Manufacturer: Supermicro
Type: Other
Lock: Not Present
Version: 0123456789
Serial Number: 0123456789
Asset Tag:
Boot-up State: Safe
Power Supply State: Safe
Thermal State: Safe
Security Status: None
OEM Information: 0x00001234

Handle 0x0004, DMI type 4, 35 bytes
Processor Information
Socket Designation: LGA771
Type: Central Processor
Family: Xeon
Manufacturer: GenuineIntel
ID: 76 06 01 00 FF FB EB BF
Signature: Type 0, Family 6, Model 23, Stepping 6 Flags:
FPU (Floating-point unit on-chip) VME (Virtual mode extension)
DE (Debugging extension)
PSE (Page size extension)
TSC (Time stamp counter)
MSR (Model specific registers)
PAE (Physical address extension) MCE (Machine check exception)
CX8 (CMPXCHG8 instruction supported) APIC (On-chip APIC hardware supported) SEP (Fast system call)
MTRR (Memory type range registers) PGE (Page global enable)
MCA (Machine check architecture) CMOV (Conditional move instruction supported) PAT (Page attribute table)
PSE-36 (36-bit page size extension) CLFSH (CLFLUSH instruction supported) DS (Debug store)
ACPI (ACPI supported)
MMX (MMX technology supported)
FXSR (Fast floating-point save and restore) SSE (Streaming SIMD extensions) SSE2 (Streaming SIMD extensions 2) SS (Self-snoop)
HTT (Hyper-threading technology)
TM (Thermal monitor supported)
PBE (Pending break enabled)
Version: Intel(R) Xeon(R) CPU X
Voltage: 1.4 V
External Clock: Unknown
Max Speed: 3200 MHz
Current Speed: 3000 MHz
Status: Populated, Enabled
Upgrade: Socket LGA771
L1 Cache Handle: 0x0006
L2 Cache Handle: 0x0007
L3 Cache Handle: Not Provided
Serial Number: Not Specified
Asset Tag: Not Specified
Part Number: Not Specified

Handle 0x0005, DMI type 4, 35 bytes
Processor Information
Socket Designation: LGA771
Type: Central Processor
Family: Xeon
Manufacturer: GenuineIntel
ID: 76 06 01 00 FF FB EB BF
Signature: Type 0, Family 6, Model 23, Stepping 6 Flags:
FPU (Floating-point unit on-chip) VME (Virtual mode extension)
DE (Debugging extension)
PSE (Page size extension)
TSC (Time stamp counter)
MSR (Model specific registers)
PAE (Physical address extension) MCE (Machine check exception)
CX8 (CMPXCHG8 instruction supported) APIC (On-chip APIC hardware supported) SEP (Fast system call)
MTRR (Memory type range registers) PGE (Page global enable)
MCA (Machine check architecture) CMOV (Conditional move instruction supported) PAT (Page attribute table)
PSE-36 (36-bit page size extension) CLFSH (CLFLUSH instruction supported) DS (Debug store)
ACPI (ACPI supported)
MMX (MMX technology supported)
FXSR (Fast floating-point save and restore) SSE (Streaming SIMD extensions) SSE2 (Streaming SIMD extensions 2) SS (Self-snoop)
HTT (Hyper-threading technology)
TM (Thermal monitor supported)
PBE (Pending break enabled)
Version: Intel(R) Xeon(R) CPU X5
Voltage: 1.4 V
External Clock: Unknown
Max Speed: 3200 MHz
Current Speed: 3000 MHz
Status: Populated, Enabled
Upgrade: Socket LGA771
L1 Cache Handle: 0x0008
L2 Cache Handle: 0x0009
L3 Cache Handle: Not Provided
Serial Number: Not Specified
Asset Tag: Not Specified
Part Number: Not Specified

Handle 0x0006, DMI type 7, 19 bytes
Cache Information
Socket Designation: L1 Cache
Configuration: Enabled, Socketed, Level 1
Operational Mode: Write Back
Location: Internal
Installed Size: 16 KB
Maximum Size: 16 KB
Supported SRAM Types:
Burst
Pipeline Burst
Asynchronous
Installed SRAM Type: Asynchronous
Speed: Unknown
Error Correction Type: Unknown
System Type: Unknown
Associativity: Unknown

Handle 0x0007, DMI type 7, 19 bytes
Cache Information
Socket Designation: L2 Cache
Configuration: Enabled, Socketed, Level 2
Operational Mode: Write Back
Location: Internal
Installed Size: 12288 KB
Maximum Size: 8192 KB
Supported SRAM Types:
Burst
Pipeline Burst
Asynchronous
Installed SRAM Type: Burst
Speed: Unknown
Error Correction Type: Unknown
System Type: Unknown
Associativity: Unknown

Handle 0x0008, DMI type 7, 19 bytes
Cache Information
Socket Designation: L1 Cache
Configuration: Enabled, Socketed, Level 1
Operational Mode: Write Back
Location: Internal
Installed Size: 16 KB
Maximum Size: 16 KB
Supported SRAM Types:
Burst
Pipeline Burst
Asynchronous
Installed SRAM Type: Asynchronous
Speed: Unknown
Error Correction Type: Unknown
System Type: Unknown
Associativity: Unknown

Handle 0x0009, DMI type 7, 19 bytes
Cache Information
Socket Designation: L2 Cache
Configuration: Enabled, Socketed, Level 2
Operational Mode: Write Back
Location: Internal
Installed Size: 12288 KB
Maximum Size: 8192 KB
Supported SRAM Types:
Burst
Pipeline Burst
Asynchronous
Installed SRAM Type: Burst
Speed: Unknown
Error Correction Type: Unknown
System Type: Unknown
Associativity: Unknown

Handle 0x000A, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: JCOM1
Internal Connector Type: 9 Pin Dual Inline (pin 10 cut) External Reference Designator: COM1
External Connector Type: DB-9 male
Port Type: Serial Port 16550A Compatible

Handle 0x000B, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: JCOM2
Internal Connector Type: 9 Pin Dual Inline (pin 10 cut) External Reference Designator: COM2
External Connector Type: DB-9 male
Port Type: Serial Port 16550A Compatible

Handle 0x000C, DMI type 9, 13 bytes
System Slot Information
Designation: PCIE#1-x16
Type: PCI Express
Current Usage: Available
Length: Other
ID: 1
Characteristics:
3.3 V is provided

Handle 0x000D, DMI type 11, 5 bytes
OEM Strings
String 1: Intel Dempsey/San Clemente/ICH9
String 2: Supermicro motherboard X7DCT

Handle 0x000E, DMI type 12, 5 bytes
System Configuration Options
Option 1: Jumper settings can be described here.

Handle 0x000F, DMI type 15, 29 bytes
System Event Log
Area Length: 192 bytes
Header Start Offset: 0x0000
Header Length: 16 bytes
Data Start Offset: 0x0010
Access Method: General-purpose non-volatile data functions Access Address: 0x0000
Status: Valid, Not Full
Change Token: 0x0000008D
Header Format: Type 1
Supported Log Type Descriptors: 3
Descriptor 1: POST error
Data Format 1: POST results bitmap
Descriptor 2: Single-bit ECC memory error
Data Format 2: Multiple-event
Descriptor 3: Multi-bit ECC memory error
Data Format 3: Multiple-event

Handle 0x0010, DMI type 16, 15 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 64 GB
Error Information Handle: Not Provided
Number Of Devices: 6

Handle 0x0011, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0010
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 1
Locator: CH0_DIMM0
Bank Locator: DIMM 0-1
Type: DDR2
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: 7F98000000000000
Serial Number: B8CC1345
Asset Tag:
Part Number:

Handle 0x0012, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0010
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 1
Locator: CH1_DIMM0
Bank Locator: DIMM 1-1
Type: DDR2
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: 7F98000000000000
Serial Number: B8CC0545
Asset Tag:
Part Number:

Handle 0x0013, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0010
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 1
Locator: CH0_DIMM1
Bank Locator: DIMM 0-2
Type: DDR2
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: 7F98000000000000
Serial Number: BACCFD44
Asset Tag:
Part Number:

Handle 0x0014, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0010
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 1
Locator: CH1_DIMM1
Bank Locator: DIMM 1-2
Type: DDR2
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: 7F98000000000000
Serial Number: B8CC0845
Asset Tag:
Part Number:

Handle 0x0015, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0010
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 1
Locator: CH0_DIMM2
Bank Locator: DIMM 0-3
Type: DDR2
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: 7F98000000000000
Serial Number: BACCF444
Asset Tag:
Part Number:

Handle 0x0016, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0010
Error Information Handle: No Error
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 1
Locator: CH1_DIMM2
Bank Locator: DIMM 1-3
Type: DDR2
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: 7F98000000000000
Serial Number: B8CC1045
Asset Tag:
Part Number:

Handle 0x0017, DMI type 19, 15 bytes
Memory Array Mapped Address

       Starting Address: 0x00000000000
       Ending Address: 0x002FFFFFFFF
       Range Size: 12 GB
       Physical Array Handle: 0x0010
       Partition Width: 0

Handle 0x0018, DMI type 20, 19 bytes
Memory Device Mapped Address
Starting Address: 0x00000000000
Ending Address: 0x0007FFFFFFF
Range Size: 2 GB
Physical Device Handle: 0x0011
Memory Array Mapped Address Handle: 0x0017
Partition Row Position: Unknown
Interleave Position: Unknown
Interleaved Data Depth: Unknown

Handle 0x0019, DMI type 20, 19 bytes
Memory Device Mapped Address
Starting Address: 0x00080000000
Ending Address: 0x000FFFFFFFF
Range Size: 2 GB
Physical Device Handle: 0x0012
Memory Array Mapped Address Handle: 0x0017
Partition Row Position: Unknown
Interleave Position: Unknown
Interleaved Data Depth: Unknown

Handle 0x001A, DMI type 20, 19 bytes
Memory Device Mapped Address
Starting Address: 0x00100000000
Ending Address: 0x0017FFFFFFF
Range Size: 2 GB
Physical Device Handle: 0x0013
Memory Array Mapped Address Handle: 0x0017
Partition Row Position: Unknown
Interleave Position: Unknown
Interleaved Data Depth: Unknown

Handle 0x001B, DMI type 23, 13 bytes
System Reset
Status: Enabled
Watchdog Timer: Present
Boot Option: Do Not Reboot
Boot Option On Limit: Do Not Reboot
Reset Count: Unknown
Reset Limit: Unknown
Timer Interval: Unknown
Timeout: Unknown

Handle 0x001C, DMI type 24, 5 bytes
Hardware Security
Power-On Password Status: Disabled
Keyboard Password Status: Unknown
Administrator Password Status: Disabled
Front Panel Reset Status: Unknown

Handle 0x001D, DMI type 25, 9 bytes
System Power Controls
Next Scheduled Power-on: 12-31 23:59:59

Handle 0x001E, DMI type 26, 20 bytes
Voltage Probe
Description: Voltage Probe
Location: Processor
Status: OK
Maximum Value: Unknown
Minimum Value: Unknown
Resolution: Unknown
Tolerance: Unknown
Accuracy: Unknown
OEM-specific Information: 0x00000000

Handle 0x001F, DMI type 27, 12 bytes
Cooling Device

       Temperature Probe Handle: 0x0020
       Type: Fan
       Status: OK
       OEM-specific Information: 0x00000000

Handle 0x0020, DMI type 28, 20 bytes
Temperature Probe
Description: Temperature Probe
Location: Processor
Status: OK
Maximum Value: Unknown
Minimum Value Unknown
Resolution: Unknown
Tolerance: Unknown
Accuracy: Unknown
OEM-specific Information: 0x00000000

Handle 0x0021, DMI type 29, 20 bytes
Electrical Current Probe
Description: Electrical Current Probe
Location: Processor
Status: OK
Maximum Value: Unknown
Minimum Value: Unknown
Resolution: Unknown
Tolerance: Unknown
Accuracy: Unknown
OEM-specific Information: 0x00000000

Handle 0x0022, DMI type 30, 6 bytes
Out-of-band Remote Access
Manufacturer Name: Intel
Inbound Connection: Disabled
Outbound Connection: Enabled

Handle 0x0023, DMI type 32, 19 bytes
System Boot Information
Status: No errors detected

Handle 0x0024, DMI type 38, 18 bytes
IPMI Device Information
Interface Type: Unknown
Specification Version: 1.0
I2C Slave Address: 0x00
NV Storage Device: Not Present
Base Address: 0x0000000000000000 (Memory-mapped) Register Spacing: Successive Byte Boundaries

Handle 0x0025, DMI type 126, 4 bytes
Inactive

Handle 0x0026, DMI type 127, 4 bytes
End Of Table

Quoted 22 lines
Quoted 16 lines

and:
ls -la /sys/class/dca/
total 0
drwxr-xr-x 2 root root 0 Jan 26 16:21 .
drwxr-xr-x 33 root root 0 Jan 26 16:14 ..

cat /sys/class/dma/dma0chan0/in_use
0
cat /sys/class/dma/dma0chan1/in_use
1
cat /sys/class/dma/dma0chan2/in_use
0
cat /sys/class/dma/dma0chan3/in_use
0

Quoted 2 lines

Why DCA is not working (or working but no info about in ioat)

The DMA channels (copy offload) are different than the DCA feature. DCA involves front side bus hints sent from the adapter to the CPU handling the interrupt, where DMA channels are for copy offload from the processor to the independent data movers (DMA channels)