http2/hpack: build static table with go generate

As the static version of headerFieldTable in hpack is generated in runtime,
we may use the go:generate to prepare the struct before the initialization phase.
This is supposed to save init time and allocations for many binaries,
as net/http imports hpack.

Before:
init golang.org/x/net/http2/hpack @1.1 ms, 0.097 ms clock, 21240 bytes, 29 allocs
After:
init golang.org/x/net/http2/hpack @0.67 ms, 0.015 ms clock, 8120 bytes, 9 allocs

Fixes golang/go#55881

Change-Id: Ia6575f67ffcba7cc4d75899b24a9c56deb58ccac
Reviewed-on: https://go-review.googlesource.com/c/net/+/434875
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
This commit is contained in:
Tomasz Jezierski
2022-09-26 23:18:22 +02:00
committed by Damien Neil
parent 430a433969
commit 84c13af5f4
4 changed files with 379 additions and 77 deletions

184
http2/hpack/gen.go Normal file
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@@ -0,0 +1,184 @@
// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//go:build ignore
// +build ignore
package main
import (
"bytes"
"fmt"
"go/format"
"io/ioutil"
"os"
"sort"
"golang.org/x/net/http2/hpack"
)
// http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-07#appendix-B
var staticTableEntries = [...]hpack.HeaderField{
{Name: ":authority"},
{Name: ":method", Value: "GET"},
{Name: ":method", Value: "POST"},
{Name: ":path", Value: "/"},
{Name: ":path", Value: "/index.html"},
{Name: ":scheme", Value: "http"},
{Name: ":scheme", Value: "https"},
{Name: ":status", Value: "200"},
{Name: ":status", Value: "204"},
{Name: ":status", Value: "206"},
{Name: ":status", Value: "304"},
{Name: ":status", Value: "400"},
{Name: ":status", Value: "404"},
{Name: ":status", Value: "500"},
{Name: "accept-charset"},
{Name: "accept-encoding", Value: "gzip, deflate"},
{Name: "accept-language"},
{Name: "accept-ranges"},
{Name: "accept"},
{Name: "access-control-allow-origin"},
{Name: "age"},
{Name: "allow"},
{Name: "authorization"},
{Name: "cache-control"},
{Name: "content-disposition"},
{Name: "content-encoding"},
{Name: "content-language"},
{Name: "content-length"},
{Name: "content-location"},
{Name: "content-range"},
{Name: "content-type"},
{Name: "cookie"},
{Name: "date"},
{Name: "etag"},
{Name: "expect"},
{Name: "expires"},
{Name: "from"},
{Name: "host"},
{Name: "if-match"},
{Name: "if-modified-since"},
{Name: "if-none-match"},
{Name: "if-range"},
{Name: "if-unmodified-since"},
{Name: "last-modified"},
{Name: "link"},
{Name: "location"},
{Name: "max-forwards"},
{Name: "proxy-authenticate"},
{Name: "proxy-authorization"},
{Name: "range"},
{Name: "referer"},
{Name: "refresh"},
{Name: "retry-after"},
{Name: "server"},
{Name: "set-cookie"},
{Name: "strict-transport-security"},
{Name: "transfer-encoding"},
{Name: "user-agent"},
{Name: "vary"},
{Name: "via"},
{Name: "www-authenticate"},
}
type pairNameValue struct {
name, value string
}
type byNameItem struct {
name string
id uint64
}
type byNameValueItem struct {
pairNameValue
id uint64
}
func headerFieldToString(f hpack.HeaderField) string {
return fmt.Sprintf("{Name: \"%s\", Value:\"%s\", Sensitive: %t}", f.Name, f.Value, f.Sensitive)
}
func pairNameValueToString(v pairNameValue) string {
return fmt.Sprintf("{name: \"%s\", value:\"%s\"}", v.name, v.value)
}
const header = `
// go generate gen.go
// Code generated by the command above; DO NOT EDIT.
package hpack
var staticTable = &headerFieldTable{
evictCount: 0,
byName: map[string]uint64{
`
//go:generate go run gen.go
func main() {
var bb bytes.Buffer
fmt.Fprintf(&bb, header)
byName := make(map[string]uint64)
byNameValue := make(map[pairNameValue]uint64)
for index, entry := range staticTableEntries {
id := uint64(index) + 1
byName[entry.Name] = id
byNameValue[pairNameValue{entry.Name, entry.Value}] = id
}
// Sort maps for deterministic generation.
byNameItems := sortByName(byName)
byNameValueItems := sortByNameValue(byNameValue)
for _, item := range byNameItems {
fmt.Fprintf(&bb, "\"%s\":%d,\n", item.name, item.id)
}
fmt.Fprintf(&bb, "},\n")
fmt.Fprintf(&bb, "byNameValue: map[pairNameValue]uint64{\n")
for _, item := range byNameValueItems {
fmt.Fprintf(&bb, "%s:%d,\n", pairNameValueToString(item.pairNameValue), item.id)
}
fmt.Fprintf(&bb, "},\n")
fmt.Fprintf(&bb, "ents: []HeaderField{\n")
for _, value := range staticTableEntries {
fmt.Fprintf(&bb, "%s,\n", headerFieldToString(value))
}
fmt.Fprintf(&bb, "},\n")
fmt.Fprintf(&bb, "}\n")
genFile("static_table.go", &bb)
}
func sortByNameValue(byNameValue map[pairNameValue]uint64) []byNameValueItem {
var byNameValueItems []byNameValueItem
for k, v := range byNameValue {
byNameValueItems = append(byNameValueItems, byNameValueItem{k, v})
}
sort.Slice(byNameValueItems, func(i, j int) bool {
return byNameValueItems[i].id < byNameValueItems[j].id
})
return byNameValueItems
}
func sortByName(byName map[string]uint64) []byNameItem {
var byNameItems []byNameItem
for k, v := range byName {
byNameItems = append(byNameItems, byNameItem{k, v})
}
sort.Slice(byNameItems, func(i, j int) bool {
return byNameItems[i].id < byNameItems[j].id
})
return byNameItems
}
func genFile(name string, buf *bytes.Buffer) {
b, err := format.Source(buf.Bytes())
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
if err := ioutil.WriteFile(name, b, 0644); err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
}

188
http2/hpack/static_table.go Normal file
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@@ -0,0 +1,188 @@
// go generate gen.go
// Code generated by the command above; DO NOT EDIT.
package hpack
var staticTable = &headerFieldTable{
evictCount: 0,
byName: map[string]uint64{
":authority": 1,
":method": 3,
":path": 5,
":scheme": 7,
":status": 14,
"accept-charset": 15,
"accept-encoding": 16,
"accept-language": 17,
"accept-ranges": 18,
"accept": 19,
"access-control-allow-origin": 20,
"age": 21,
"allow": 22,
"authorization": 23,
"cache-control": 24,
"content-disposition": 25,
"content-encoding": 26,
"content-language": 27,
"content-length": 28,
"content-location": 29,
"content-range": 30,
"content-type": 31,
"cookie": 32,
"date": 33,
"etag": 34,
"expect": 35,
"expires": 36,
"from": 37,
"host": 38,
"if-match": 39,
"if-modified-since": 40,
"if-none-match": 41,
"if-range": 42,
"if-unmodified-since": 43,
"last-modified": 44,
"link": 45,
"location": 46,
"max-forwards": 47,
"proxy-authenticate": 48,
"proxy-authorization": 49,
"range": 50,
"referer": 51,
"refresh": 52,
"retry-after": 53,
"server": 54,
"set-cookie": 55,
"strict-transport-security": 56,
"transfer-encoding": 57,
"user-agent": 58,
"vary": 59,
"via": 60,
"www-authenticate": 61,
},
byNameValue: map[pairNameValue]uint64{
{name: ":authority", value: ""}: 1,
{name: ":method", value: "GET"}: 2,
{name: ":method", value: "POST"}: 3,
{name: ":path", value: "/"}: 4,
{name: ":path", value: "/index.html"}: 5,
{name: ":scheme", value: "http"}: 6,
{name: ":scheme", value: "https"}: 7,
{name: ":status", value: "200"}: 8,
{name: ":status", value: "204"}: 9,
{name: ":status", value: "206"}: 10,
{name: ":status", value: "304"}: 11,
{name: ":status", value: "400"}: 12,
{name: ":status", value: "404"}: 13,
{name: ":status", value: "500"}: 14,
{name: "accept-charset", value: ""}: 15,
{name: "accept-encoding", value: "gzip, deflate"}: 16,
{name: "accept-language", value: ""}: 17,
{name: "accept-ranges", value: ""}: 18,
{name: "accept", value: ""}: 19,
{name: "access-control-allow-origin", value: ""}: 20,
{name: "age", value: ""}: 21,
{name: "allow", value: ""}: 22,
{name: "authorization", value: ""}: 23,
{name: "cache-control", value: ""}: 24,
{name: "content-disposition", value: ""}: 25,
{name: "content-encoding", value: ""}: 26,
{name: "content-language", value: ""}: 27,
{name: "content-length", value: ""}: 28,
{name: "content-location", value: ""}: 29,
{name: "content-range", value: ""}: 30,
{name: "content-type", value: ""}: 31,
{name: "cookie", value: ""}: 32,
{name: "date", value: ""}: 33,
{name: "etag", value: ""}: 34,
{name: "expect", value: ""}: 35,
{name: "expires", value: ""}: 36,
{name: "from", value: ""}: 37,
{name: "host", value: ""}: 38,
{name: "if-match", value: ""}: 39,
{name: "if-modified-since", value: ""}: 40,
{name: "if-none-match", value: ""}: 41,
{name: "if-range", value: ""}: 42,
{name: "if-unmodified-since", value: ""}: 43,
{name: "last-modified", value: ""}: 44,
{name: "link", value: ""}: 45,
{name: "location", value: ""}: 46,
{name: "max-forwards", value: ""}: 47,
{name: "proxy-authenticate", value: ""}: 48,
{name: "proxy-authorization", value: ""}: 49,
{name: "range", value: ""}: 50,
{name: "referer", value: ""}: 51,
{name: "refresh", value: ""}: 52,
{name: "retry-after", value: ""}: 53,
{name: "server", value: ""}: 54,
{name: "set-cookie", value: ""}: 55,
{name: "strict-transport-security", value: ""}: 56,
{name: "transfer-encoding", value: ""}: 57,
{name: "user-agent", value: ""}: 58,
{name: "vary", value: ""}: 59,
{name: "via", value: ""}: 60,
{name: "www-authenticate", value: ""}: 61,
},
ents: []HeaderField{
{Name: ":authority", Value: "", Sensitive: false},
{Name: ":method", Value: "GET", Sensitive: false},
{Name: ":method", Value: "POST", Sensitive: false},
{Name: ":path", Value: "/", Sensitive: false},
{Name: ":path", Value: "/index.html", Sensitive: false},
{Name: ":scheme", Value: "http", Sensitive: false},
{Name: ":scheme", Value: "https", Sensitive: false},
{Name: ":status", Value: "200", Sensitive: false},
{Name: ":status", Value: "204", Sensitive: false},
{Name: ":status", Value: "206", Sensitive: false},
{Name: ":status", Value: "304", Sensitive: false},
{Name: ":status", Value: "400", Sensitive: false},
{Name: ":status", Value: "404", Sensitive: false},
{Name: ":status", Value: "500", Sensitive: false},
{Name: "accept-charset", Value: "", Sensitive: false},
{Name: "accept-encoding", Value: "gzip, deflate", Sensitive: false},
{Name: "accept-language", Value: "", Sensitive: false},
{Name: "accept-ranges", Value: "", Sensitive: false},
{Name: "accept", Value: "", Sensitive: false},
{Name: "access-control-allow-origin", Value: "", Sensitive: false},
{Name: "age", Value: "", Sensitive: false},
{Name: "allow", Value: "", Sensitive: false},
{Name: "authorization", Value: "", Sensitive: false},
{Name: "cache-control", Value: "", Sensitive: false},
{Name: "content-disposition", Value: "", Sensitive: false},
{Name: "content-encoding", Value: "", Sensitive: false},
{Name: "content-language", Value: "", Sensitive: false},
{Name: "content-length", Value: "", Sensitive: false},
{Name: "content-location", Value: "", Sensitive: false},
{Name: "content-range", Value: "", Sensitive: false},
{Name: "content-type", Value: "", Sensitive: false},
{Name: "cookie", Value: "", Sensitive: false},
{Name: "date", Value: "", Sensitive: false},
{Name: "etag", Value: "", Sensitive: false},
{Name: "expect", Value: "", Sensitive: false},
{Name: "expires", Value: "", Sensitive: false},
{Name: "from", Value: "", Sensitive: false},
{Name: "host", Value: "", Sensitive: false},
{Name: "if-match", Value: "", Sensitive: false},
{Name: "if-modified-since", Value: "", Sensitive: false},
{Name: "if-none-match", Value: "", Sensitive: false},
{Name: "if-range", Value: "", Sensitive: false},
{Name: "if-unmodified-since", Value: "", Sensitive: false},
{Name: "last-modified", Value: "", Sensitive: false},
{Name: "link", Value: "", Sensitive: false},
{Name: "location", Value: "", Sensitive: false},
{Name: "max-forwards", Value: "", Sensitive: false},
{Name: "proxy-authenticate", Value: "", Sensitive: false},
{Name: "proxy-authorization", Value: "", Sensitive: false},
{Name: "range", Value: "", Sensitive: false},
{Name: "referer", Value: "", Sensitive: false},
{Name: "refresh", Value: "", Sensitive: false},
{Name: "retry-after", Value: "", Sensitive: false},
{Name: "server", Value: "", Sensitive: false},
{Name: "set-cookie", Value: "", Sensitive: false},
{Name: "strict-transport-security", Value: "", Sensitive: false},
{Name: "transfer-encoding", Value: "", Sensitive: false},
{Name: "user-agent", Value: "", Sensitive: false},
{Name: "vary", Value: "", Sensitive: false},
{Name: "via", Value: "", Sensitive: false},
{Name: "www-authenticate", Value: "", Sensitive: false},
},
}

View File

@@ -96,8 +96,7 @@ func (t *headerFieldTable) evictOldest(n int) {
// meaning t.ents is reversed for dynamic tables. Hence, when t is a dynamic
// table, the return value i actually refers to the entry t.ents[t.len()-i].
//
// All tables are assumed to be a dynamic tables except for the global
// staticTable pointer.
// All tables are assumed to be a dynamic tables except for the global staticTable.
//
// See Section 2.3.3.
func (t *headerFieldTable) search(f HeaderField) (i uint64, nameValueMatch bool) {
@@ -125,81 +124,6 @@ func (t *headerFieldTable) idToIndex(id uint64) uint64 {
return k + 1
}
// http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-07#appendix-B
var staticTable = newStaticTable()
var staticTableEntries = [...]HeaderField{
{Name: ":authority"},
{Name: ":method", Value: "GET"},
{Name: ":method", Value: "POST"},
{Name: ":path", Value: "/"},
{Name: ":path", Value: "/index.html"},
{Name: ":scheme", Value: "http"},
{Name: ":scheme", Value: "https"},
{Name: ":status", Value: "200"},
{Name: ":status", Value: "204"},
{Name: ":status", Value: "206"},
{Name: ":status", Value: "304"},
{Name: ":status", Value: "400"},
{Name: ":status", Value: "404"},
{Name: ":status", Value: "500"},
{Name: "accept-charset"},
{Name: "accept-encoding", Value: "gzip, deflate"},
{Name: "accept-language"},
{Name: "accept-ranges"},
{Name: "accept"},
{Name: "access-control-allow-origin"},
{Name: "age"},
{Name: "allow"},
{Name: "authorization"},
{Name: "cache-control"},
{Name: "content-disposition"},
{Name: "content-encoding"},
{Name: "content-language"},
{Name: "content-length"},
{Name: "content-location"},
{Name: "content-range"},
{Name: "content-type"},
{Name: "cookie"},
{Name: "date"},
{Name: "etag"},
{Name: "expect"},
{Name: "expires"},
{Name: "from"},
{Name: "host"},
{Name: "if-match"},
{Name: "if-modified-since"},
{Name: "if-none-match"},
{Name: "if-range"},
{Name: "if-unmodified-since"},
{Name: "last-modified"},
{Name: "link"},
{Name: "location"},
{Name: "max-forwards"},
{Name: "proxy-authenticate"},
{Name: "proxy-authorization"},
{Name: "range"},
{Name: "referer"},
{Name: "refresh"},
{Name: "retry-after"},
{Name: "server"},
{Name: "set-cookie"},
{Name: "strict-transport-security"},
{Name: "transfer-encoding"},
{Name: "user-agent"},
{Name: "vary"},
{Name: "via"},
{Name: "www-authenticate"},
}
func newStaticTable() *headerFieldTable {
t := &headerFieldTable{}
t.init()
for _, e := range staticTableEntries[:] {
t.addEntry(e)
}
return t
}
var huffmanCodes = [256]uint32{
0x1ff8,
0x7fffd8,

View File

@@ -207,6 +207,12 @@ func TestStaticTable(t *testing.T) {
if got, want := staticTable.ents[i-1].Value, m[3]; got != want {
t.Errorf("header index %d value = %q; want %q", i, got, want)
}
if got, want := staticTable.ents[i-1].Sensitive, false; got != want {
t.Errorf("header index %d sensitive = %t; want %t", i, got, want)
}
if got, want := strconv.Itoa(int(staticTable.byNameValue[pairNameValue{name: m[2], value: m[3]}])), m[1]; got != want {
t.Errorf("header by name %s value %s index = %s; want %s", m[2], m[3], got, want)
}
}
if err := bs.Err(); err != nil {
t.Error(err)