diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/transport/control.go')
-rw-r--r-- | vendor/google.golang.org/grpc/transport/control.go | 174 |
1 files changed, 139 insertions, 35 deletions
diff --git a/vendor/google.golang.org/grpc/transport/control.go b/vendor/google.golang.org/grpc/transport/control.go index 8d29aee..dd1a8d4 100644 --- a/vendor/google.golang.org/grpc/transport/control.go +++ b/vendor/google.golang.org/grpc/transport/control.go @@ -1,33 +1,18 @@ /* * - * Copyright 2014, Google Inc. - * All rights reserved. + * Copyright 2014 gRPC authors. * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are - * met: + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at * - * * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * * Redistributions in binary form must reproduce the above - * copyright notice, this list of conditions and the following disclaimer - * in the documentation and/or other materials provided with the - * distribution. - * * Neither the name of Google Inc. nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. + * http://www.apache.org/licenses/LICENSE-2.0 * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. * */ @@ -37,17 +22,18 @@ import ( "fmt" "math" "sync" + "sync/atomic" "time" "golang.org/x/net/http2" + "golang.org/x/net/http2/hpack" ) const ( // The default value of flow control window size in HTTP2 spec. defaultWindowSize = 65535 // The initial window size for flow control. - initialWindowSize = defaultWindowSize // for an RPC - initialConnWindowSize = defaultWindowSize * 16 // for a connection + initialWindowSize = defaultWindowSize // for an RPC infinity = time.Duration(math.MaxInt64) defaultClientKeepaliveTime = infinity defaultClientKeepaliveTimeout = time.Duration(20 * time.Second) @@ -58,11 +44,43 @@ const ( defaultServerKeepaliveTime = time.Duration(2 * time.Hour) defaultServerKeepaliveTimeout = time.Duration(20 * time.Second) defaultKeepalivePolicyMinTime = time.Duration(5 * time.Minute) + // max window limit set by HTTP2 Specs. + maxWindowSize = math.MaxInt32 + // defaultLocalSendQuota sets is default value for number of data + // bytes that each stream can schedule before some of it being + // flushed out. + defaultLocalSendQuota = 64 * 1024 ) // The following defines various control items which could flow through // the control buffer of transport. They represent different aspects of // control tasks, e.g., flow control, settings, streaming resetting, etc. + +type headerFrame struct { + streamID uint32 + hf []hpack.HeaderField + endStream bool +} + +func (*headerFrame) item() {} + +type continuationFrame struct { + streamID uint32 + endHeaders bool + headerBlockFragment []byte +} + +type dataFrame struct { + streamID uint32 + endStream bool + d []byte + f func() +} + +func (*dataFrame) item() {} + +func (*continuationFrame) item() {} + type windowUpdate struct { streamID uint32 increment uint32 @@ -87,6 +105,8 @@ func (*resetStream) item() {} type goAway struct { code http2.ErrCode debugData []byte + headsUp bool + closeConn bool } func (*goAway) item() {} @@ -108,8 +128,9 @@ func (*ping) item() {} type quotaPool struct { c chan int - mu sync.Mutex - quota int + mu sync.Mutex + version uint32 + quota int } // newQuotaPool creates a quotaPool which has quota q available to consume. @@ -130,6 +151,10 @@ func newQuotaPool(q int) *quotaPool { func (qb *quotaPool) add(v int) { qb.mu.Lock() defer qb.mu.Unlock() + qb.lockedAdd(v) +} + +func (qb *quotaPool) lockedAdd(v int) { select { case n := <-qb.c: qb.quota += n @@ -150,6 +175,35 @@ func (qb *quotaPool) add(v int) { } } +func (qb *quotaPool) addAndUpdate(v int) { + qb.mu.Lock() + defer qb.mu.Unlock() + qb.lockedAdd(v) + // Update the version only after having added to the quota + // so that if acquireWithVesrion sees the new vesrion it is + // guaranteed to have seen the updated quota. + // Also, still keep this inside of the lock, so that when + // compareAndExecute is processing, this function doesn't + // get executed partially (quota gets updated but the version + // doesn't). + atomic.AddUint32(&(qb.version), 1) +} + +func (qb *quotaPool) acquireWithVersion() (<-chan int, uint32) { + return qb.c, atomic.LoadUint32(&(qb.version)) +} + +func (qb *quotaPool) compareAndExecute(version uint32, success, failure func()) bool { + qb.mu.Lock() + defer qb.mu.Unlock() + if version == atomic.LoadUint32(&(qb.version)) { + success() + return true + } + failure() + return false +} + // acquire returns the channel on which available quota amounts are sent. func (qb *quotaPool) acquire() <-chan int { return qb.c @@ -157,16 +211,59 @@ func (qb *quotaPool) acquire() <-chan int { // inFlow deals with inbound flow control type inFlow struct { + mu sync.Mutex // The inbound flow control limit for pending data. limit uint32 - - mu sync.Mutex // pendingData is the overall data which have been received but not been // consumed by applications. pendingData uint32 // The amount of data the application has consumed but grpc has not sent // window update for them. Used to reduce window update frequency. pendingUpdate uint32 + // delta is the extra window update given by receiver when an application + // is reading data bigger in size than the inFlow limit. + delta uint32 +} + +// newLimit updates the inflow window to a new value n. +// It assumes that n is always greater than the old limit. +func (f *inFlow) newLimit(n uint32) uint32 { + f.mu.Lock() + defer f.mu.Unlock() + d := n - f.limit + f.limit = n + return d +} + +func (f *inFlow) maybeAdjust(n uint32) uint32 { + if n > uint32(math.MaxInt32) { + n = uint32(math.MaxInt32) + } + f.mu.Lock() + defer f.mu.Unlock() + // estSenderQuota is the receiver's view of the maximum number of bytes the sender + // can send without a window update. + estSenderQuota := int32(f.limit - (f.pendingData + f.pendingUpdate)) + // estUntransmittedData is the maximum number of bytes the sends might not have put + // on the wire yet. A value of 0 or less means that we have already received all or + // more bytes than the application is requesting to read. + estUntransmittedData := int32(n - f.pendingData) // Casting into int32 since it could be negative. + // This implies that unless we send a window update, the sender won't be able to send all the bytes + // for this message. Therefore we must send an update over the limit since there's an active read + // request from the application. + if estUntransmittedData > estSenderQuota { + // Sender's window shouldn't go more than 2^31 - 1 as speecified in the HTTP spec. + if f.limit+n > maxWindowSize { + f.delta = maxWindowSize - f.limit + } else { + // Send a window update for the whole message and not just the difference between + // estUntransmittedData and estSenderQuota. This will be helpful in case the message + // is padded; We will fallback on the current available window(at least a 1/4th of the limit). + f.delta = n + } + return f.delta + } + return 0 } // onData is invoked when some data frame is received. It updates pendingData. @@ -174,7 +271,7 @@ func (f *inFlow) onData(n uint32) error { f.mu.Lock() defer f.mu.Unlock() f.pendingData += n - if f.pendingData+f.pendingUpdate > f.limit { + if f.pendingData+f.pendingUpdate > f.limit+f.delta { return fmt.Errorf("received %d-bytes data exceeding the limit %d bytes", f.pendingData+f.pendingUpdate, f.limit) } return nil @@ -189,6 +286,13 @@ func (f *inFlow) onRead(n uint32) uint32 { return 0 } f.pendingData -= n + if n > f.delta { + n -= f.delta + f.delta = 0 + } else { + f.delta -= n + n = 0 + } f.pendingUpdate += n if f.pendingUpdate >= f.limit/4 { wu := f.pendingUpdate @@ -198,10 +302,10 @@ func (f *inFlow) onRead(n uint32) uint32 { return 0 } -func (f *inFlow) resetPendingData() uint32 { +func (f *inFlow) resetPendingUpdate() uint32 { f.mu.Lock() defer f.mu.Unlock() - n := f.pendingData - f.pendingData = 0 + n := f.pendingUpdate + f.pendingUpdate = 0 return n } |