Simple JIT compiler to create a fixed-size page translation cache. Generates simple linear search code without branches. On small tables it costs about 16 cycles including the overhead of looping and calling from Lua.
Cache table layout:
struct tlb_entry { int64_t page, offset; }
JIT compiler source:
| Exerpt from `perf top`: | |
| ``` | |
| 25.29% perf-26553.map [.] TRACE_7::lib/virtio/net_device.lua:161 | |
| 22.10% perf-26553.map [.] TRACE_19::lib/virtio/net_device.lua:236 | |
| 7.63% perf-26553.map [.] TRACE_15::apps/intel/intel_app.lua:77 | |
| 6.37% snabb [.] lj_alloc_free | |
| 6.22% snabb [.] release_unused_segments | |
| 4.73% perf-26553.map [.] TRACE_14::apps/intel/intel_app.lua:92 | |
| 3.93% snabb [.] packet_reset |
| link report | |
| 9,993,377 sent on vm.tx -> nic.rx (loss rate: 0%) | |
| 10,000,116 sent on nic.tx -> vm.rx (loss rate: 0%) | |
| Processed 10.0 million packets in 3.93 seconds | |
| Made 184,436 breaths: 54.22 packets per breath; 21.28us per breath | |
| Rate(Mpps): 2.548 | |
| 98% Compiled | |
| -- 24% tlb.lua:lookup | |
| -- 12% net_device.lua:vm_buffer |
| luke@grindelwald:~/hacking/snabbswitch/src$ for i in $(seq 1 10); do make && sudo SNABB=$(pwd)/snabb NFV_PACKETS=10e6 scripts/bench_env/loadgen-snabb-nic-guest.sh; done | grep Mpps | |
| Rate(Mpps): 4.804 | |
| Rate(Mpps): 5.200 | |
| Rate(Mpps): 4.746 | |
| Rate(Mpps): 4.797 | |
| Rate(Mpps): 4.575 | |
| Rate(Mpps): 3.330 | |
| Rate(Mpps): 4.684 | |
| Rate(Mpps): 4.424 | |
| Rate(Mpps): 4.632 |
| core/freelist.lua:14: freelist overflow | |
| stack traceback: | |
| core/main.lua:137: in function <core/main.lua:135> | |
| [C]: in function 'assert' | |
| core/freelist.lua:14: in function 'add' | |
| lib/virtio/net_device.lua:182: in function 'get_transmit_buffers_from_vm' | |
| lib/virtio/net_device.lua:79: in function 'poll_vring_transmit' | |
| apps/vhost/vhost_user.lua:58: in function 'push' | |
| core/app.lua:189: in function 'breathe' | |
| core/app.lua:144: in function 'main' |
| diff --git a/src/apps/intel/intel10g.lua b/src/apps/intel/intel10g.lua | |
| index 9882b96..ca2d0e0 100644 | |
| --- a/src/apps/intel/intel10g.lua | |
| +++ b/src/apps/intel/intel10g.lua | |
| @@ -277,7 +277,7 @@ end | |
| function set_SFI (dev) | |
| local autoc = dev.r.AUTOC() | |
| autoc = bor( | |
| - band(autoc, 0xFFFF0C7E), -- clears FLU, 10g_pma, 1g_pma, restart_AN, LMS | |
| + band(autoc, 0xFFFF0C7F), -- sets FLU; clears 10g_pma, 1g_pma, restart_AN, LMS |
| On 0000:01:00.0 got 3.652 | |
| On 0000:03:00.0 got 3.509 | |
| On 0000:05:00.0 got 3.688 | |
| On 0000:08:00.0 got 3.713 | |
| On 0000:82:00.0 got 3.682 | |
| On 0000:84:00.0 got 3.596 | |
| On 0000:86:00.0 got 3.759 | |
| On 0000:89:00.0 got 3.753 | |
| Rate(Mpps): 29.352 |
| #!/usr/bin/env bash | |
| # Mandatory Parameters: | |
| # EVENTS_IN: Directory to read incoming events | |
| # EVENTS_OUT: Directory to write accepted events | |
| # | |
| # Optional Parameters: | |
| # PROJECT: Project name (regex fragment) | |
| # EVENTS_SKIP: Directory to write skipped events |
| # -*- mode: ruby -*- | |
| # vi: set ft=ruby : | |
| # Vagrantfile API/syntax version. Don't touch unless you know what you're doing! | |
| VAGRANTFILE_API_VERSION = "2" | |
| Vagrant.configure(VAGRANTFILE_API_VERSION) do |config| | |
| config.vm.box = "trusty" | |
| config.vm.provision "shell", path: "ci.sh" | |
| config.vm.provider "virtualbox" do |vb| |
| CC [M] /home/luke/github/Pktgen-DPDK.release/dpdk/x86_64-pktgen-linuxapp-gcc/build/lib/librte_eal/linuxapp/kni/igb_main.o | |
| /home/luke/github/Pktgen-DPDK.release/dpdk/x86_64-pktgen-linuxapp-gcc/build/lib/librte_eal/linuxapp/kni/igb_main.c: In function ‘igb_rx_hash’: | |
| /home/luke/github/Pktgen-DPDK.release/dpdk/x86_64-pktgen-linuxapp-gcc/build/lib/librte_eal/linuxapp/kni/igb_main.c:7379:3: error: implicit declaration of function ‘skb_set_hash’ [-Werror=implicit-function-declaration] | |
| skb_set_hash(skb, le32_to_cpu(rx_desc->wb.lower.hi_dword.rss), | |
| ^ | |
| /home/luke/github/Pktgen-DPDK.release/dpdk/x86_64-pktgen-linuxapp-gcc/build/lib/librte_eal/linuxapp/kni/igb_main.c:7380:9: error: ‘PKT_HASH_TYPE_L3’ undeclared (first use in this function) | |
| PKT_HASH_TYPE_L3); | |
| ^ | |
| /home/luke/github/Pktgen-DPDK.release/dpdk/x86_64-pktgen-linuxapp-gcc/build/lib/librte_eal/linuxapp/kni/igb_main.c:7380:9: note: each undeclared identifier is reported only once for each function it appears in | |
| cc1: all warnings being treat |