linux/drivers/net/s2io.h

1037 lines
28 KiB

[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 14:55:46 +01:00
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 14:55:46 +01:00
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 14:55:46 +01:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00
[PATCH] S2io: Large Receive Offload (LRO) feature(v2) for Neterion (s2io) 10GbE Xframe PCI-X and PCI-E NICs Hi, Below is a patch for the Large Receive Offload feature. Please review and let us know your comments. LRO algorithm was described in an OLS 2005 presentation, located at ftp.s2io.com user: linuxdocs password: HALdocs The same ftp site has Programming Manual for Xframe-I ASIC. LRO feature is supported on Neterion Xframe-I, Xframe-II and Xframe-Express 10GbE NICs. Brief description: The Large Receive Offload(LRO) feature is a stateless offload that is complementary to TSO feature but on the receive path. The idea is to combine and collapse(upto 64K maximum) in the driver, in-sequence TCP packets belonging to the same session. It is mainly designed to improve 1500 mtu receive performance, since Jumbo frame performance is already close to 10GbE line rate. Some performance numbers are attached below. Implementation details: 1. Handle packet chains from multiple sessions(current default MAX_LRO_SESSSIONS=32). 2. Examine each packet for eligiblity to aggregate. A packet is considered eligible if it meets all the below criteria. a. It is a TCP/IP packet and L2 type is not LLC or SNAP. b. The packet has no checksum errors(L3 and L4). c. There are no IP options. The only TCP option supported is timestamps. d. Search and locate the LRO object corresponding to this socket and ensure packet is in TCP sequence. e. It's not a special packet(SYN, FIN, RST, URG, PSH etc. flags are not set). f. TCP payload is non-zero(It's not a pure ACK). g. It's not an IP-fragmented packet. 3. If a packet is found eligible, the LRO object is updated with information such as next sequence number expected, current length of aggregated packet and so on. If not eligible or max packets reached, update IP and TCP headers of first packet in the chain and pass it up to stack. 4. The frag_list in skb structure is used to chain packets into one large packet. Kernel changes required: None Performance results: Main focus of the initial testing was on 1500 mtu receiver, since this is a bottleneck not covered by the existing stateless offloads. There are couple disclaimers about the performance results below: 1. Your mileage will vary!!!! We initially concentrated on couple pci-x 2.0 platforms that are powerful enough to push 10 GbE NIC and do not have bottlenecks other than cpu%; testing on other platforms is still in progress. On some lower end systems we are seeing lower gains. 2. Current LRO implementation is still (for the most part) software based, and therefore performance potential of the feature is far from being realized. Full hw implementation of LRO is expected in the next version of Xframe ASIC. Performance delta(with MTU=1500) going from LRO disabled to enabled: IBM 2-way Xeon (x366) : 3.5 to 7.1 Gbps 2-way Opteron : 4.5 to 6.1 Gbps Signed-off-by: Ravinandan Arakali <ravinandan.arakali@neterion.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-25 14:53:07 -05:00