Commit Graph

69 Commits

Author SHA1 Message Date
Scott Mitchell
ed0668384b NIO read spin event loop spin when half closed (#7801)
Motivation:
AbstractNioByteChannel will detect that the remote end of the socket has
been closed and propagate a user event through the pipeline. However if
the user has auto read on, or calls read again, we may propagate the
same user events again. If the underlying transport continuously
notifies us that there is read activity this will happen in a spin loop
which consumes unnecessary CPU.

Modifications:
- AbstractNioByteChannel's unsafe read() should check if the input side
of the socket has been shutdown before processing the event. This is
consistent with EPOLL and KQUEUE transports.
- add unit test with @normanmaurer's help, and make transports consistent with respect to user events

Result:
No more read spin loop in NIO when the channel is half closed.
2018-03-28 20:02:57 +02:00
Norman Maurer
0a8e1aaf19 Flush task should not flush messages that were written since last flush attempt.
Motivation:

The flush task is currently using flush() which will have the affect of have the flush traverse the whole ChannelPipeline and also flush messages that were written since we gave up flushing. This is not really correct as we should only continue to flush messages that were flushed at the point in time when the flush task was submitted for execution if the user not explicit call flush() by him/herself.

Modification:

Call *Unsafe.flush0() via the flush task which will only continue flushing messages that were marked as flushed before.

Result:

More correct behaviour when the flush task is used.
2018-03-02 10:09:40 +09:00
Norman Maurer
69582c0b6c [maven-release-plugin] prepare for next development iteration 2018-02-21 12:52:33 +00:00
Norman Maurer
786f35c6c9 [maven-release-plugin] prepare release netty-4.1.22.Final 2018-02-21 12:52:19 +00:00
Scott Mitchell
d2d3e6ef0c
KQueue write filter initial state (#7738)
Motivation:
KQueue implementations current have inconsistent behavior with Epoll implementations with respect to asynchronous sockets and connecting. In the Epoll transport we attempt to connect, if the connect call does not synchornously fail/succeed we set the EPOLLOUT which will be triggered by the kernel if the connection attempt succeeds or an error occurs. The connect API provides no way to asynchronously communicate an error so the Epoll implementation fires a EPOLLOUT event and puts the connect status in getsockopt(SO_ERROR). KQueue provides the same APIs but different behavior. If the EVFILT_WRITE is not enabled and the EVFILT_READ is enabled before connect is called, and there is an error the kernel may fire the EVFILT_READ filter and provide the Connection Refused error via read(). This is even true if we set the EVFILT_WRITE filter after calling connect because connect didn't synchornously complete. After the error has been delievered via read() a call to getsockopt(SO_ERROR) will return 0 indicating there is no error. This means we cannot rely upon the KQueue based kernel to deliver connection errors via the EVFILT_WRITE filter in the same way that the linux kernel does with the EPOLLOUT flag.
ce241bd introduced a change which depends upon the behavior of the EVFILT_WRITE being set and may prematurely stop writing to the OS as a result, becaues we assume the OS will notify us when the socket is writable. However the current work around for the above described behavior is to initialize the EVFILT_WRITE to true for connection oriented protocols. This leads to prematurely exiting from the flush() which may lead to deadlock.

Modifications:
- KQueue should check when an error is obtained from read() if the connectPromise has not yet been completed, and if not complete it with a ConnectException

Result:
No more deadlock in KQueue due to asynchronous connect workaround.
2018-02-20 11:01:49 -08:00
Scott Mitchell
ce241bd11e Epoll flush/writabilityChange deadlock
Motivation:
b215794de3 recently introduced a change in behavior where writeSpinCount provided a limit for how many write operations were attempted per flush operation. However when the write quantum was meet the selector write flag was not cleared, and the channel unsafe flush0 method has an optimization which prematurely exits if the write flag is set. This may lead to no write progress being made under the following scenario:
- flush is called, but the socket can't accept all data, we set the write flag
- the selector wakes us up because the socket is writable, we write data and use the writeSpinCount quantum
- we then schedule a flush() on the EventLoop to execute later, however it the flush0 optimization prematurely exits because the write flag is still set

In this scenario the socket is still writable so the EventLoop may never notify us that the socket is writable, and therefore we may never attempt to flush data to the OS.

Modifications:
- When the writeSpinCount quantum is exceeded we should clear the selector write flag

Result:
Fixes https://github.com/netty/netty/issues/7729
2018-02-20 11:40:58 +01:00
Norman Maurer
e71fa1e7b6 [maven-release-plugin] prepare for next development iteration 2018-02-05 12:02:35 +00:00
Norman Maurer
41ebb5fcca [maven-release-plugin] prepare release netty-4.1.21.Final 2018-02-05 12:02:19 +00:00
Norman Maurer
ea58dc7ac7 [maven-release-plugin] prepare for next development iteration 2018-01-21 12:53:51 +00:00
Norman Maurer
96c7132dee [maven-release-plugin] prepare release netty-4.1.20.Final 2018-01-21 12:53:34 +00:00
Scott Mitchell
33ddb83dc1
IovArray#add return value resulted in more ByteBufs being added during iteration
Motivation:
IovArray implements MessageProcessor, and the processMessage method will continue to be called during iteration until it returns true. A recent commit b215794de3 changed the return value to only return true if any component of a CompositeByteBuf was added as a result of the method call. However this results in the iteration continuing, and potentially subsequent smaller buffers maybe added, which will result in out of order writes and generally corrupts data.

Modifications:
- IovArray#add should return false so that the MessageProcessor#processMessage will stop iterating.

Result:
Native transports which use IovArray will not corrupt data during gathering writes of CompositeByteBuf objects.
2018-01-04 08:04:32 -08:00
Norman Maurer
264a5daa41 [maven-release-plugin] prepare for next development iteration 2017-12-15 13:10:54 +00:00
Norman Maurer
0786c4c8d9 [maven-release-plugin] prepare release netty-4.1.19.Final 2017-12-15 13:09:30 +00:00
Scott Mitchell
af2f343648
FileDescriptor writev core dump
Motivation:
FileDescriptor#writev calls JNI code, and that JNI code dereferences a NULL pointer which crashes the application. This occurs when writing a single CompositeByteBuf object with more than one component.

Modifications:
- Initialize the iovec iterator properly to avoid the core dump
- Fix the array length calculation if we aren't able to fit all the ByteBuffer objects in the iovec array

Result:
No more core dump.
2017-12-14 16:47:31 -08:00
Dmitriy Dumanskiy
8b3e98163d Added Automatic-Module-Name for native modules to support Java 9 modules
Motivation:

Latest netty missing predefined Automatic-Module-Name module name entry in MANIFEST.MF for native transports.

Modification:

Added Automatic-Module-Name entry to manifest during native transports build.

Fixes [#7501]
2017-12-14 19:41:45 +00:00
Norman Maurer
b2bc6407ab [maven-release-plugin] prepare for next development iteration 2017-12-08 09:26:15 +00:00
Norman Maurer
96732f47d8 [maven-release-plugin] prepare release netty-4.1.18.Final 2017-12-08 09:25:56 +00:00
Scott Mitchell
b215794de3
Enforce writeSpinCount to limit resource consumption per socket (#7478)
Motivation:
The writeSpinCount currently loops over the same buffer, gathering
write, file write, or other write operation multiple times but will
continue writing until there is nothing left or the OS doesn't accept
any data for that specific write. However if the OS keeps accepting
writes there is no way to limit how much time we spend on a specific
socket. This can lead to unfair consumption of resources dedicated to a
single socket.
We currently don't limit the amount of bytes we attempt to write per
gathering write. If there are many more bytes pending relative to the
SO_SNDBUF size we will end up building iov arrays with more elements
than can be written, which results in extra iteration, conditionals,
and book keeping.

Modifications:
- writeSpinCount should limit the number of system calls we make to
write data, instead of applying to individual write operations
- IovArray should support a maximum number of bytes
- IovArray should support composite buffers of greater than size 1024
- We should auto-scale the amount of data that we attempt to write per
gathering write operation relative to SO_SNDBUF and how much data is
successfully written
- The non-unsafe path should also support a maximum number of bytes,
and respect the IOV_MAX limit

Result:
Write resource consumption can be bounded and gathering writes have
a limit relative to the amount of data which can actually be accepted
by the socket.
2017-12-07 16:00:52 -08:00
Norman Maurer
3f101caa4c Not call java methods from within JNI init code to prevent class loading deadlocks.
Motivation:

We used NetUtil.isIpV4StackPreferred() when loading JNI code which tries to load NetworkInterface in its static initializer. Unfortunally a lock on the NetworkInterface class init may be already hold somewhere else which may cause a loader deadlock.

Modifications:

Add a new Socket.initialize() method that will be called when init the library and pass everything needed to the JNI level so we not need to call back to java.

Result:

Fixes [#7458].
2017-12-06 14:34:15 +01:00
Norman Maurer
251bb1a739 Not use safeRelease(...) but release(...) to release non-readable holders to ensure we not mask errors.
Motivation:

AbstractChannel attempts to "filter" messages which are written [1]. A goal of this process is to copy from heap to direct if necessary. However implementations of this method [2][3] may translate a buffer with 0 readable bytes to EMPTY_BUFFER. This may mask a user error where an empty buffer is written but already released.

Modifications:

Replace safeRelease(...) with release(...) to ensure we propagate reference count issues.

Result:

Fixes [#7383]
2017-12-04 20:38:35 +01:00
Tomasz Jędrzejewski
e8540c2b7a Adding stable JDK9 module names that follow reverse-DNS style
Automatic-Module-Name entry provides a stable JDK9 module name, when Netty is used in a modular JDK9 applications. More info: http://blog.joda.org/2017/05/java-se-9-jpms-automatic-modules.html

When Netty migrates to JDK9 in the future, the entry can be replaced by actual module-info descriptor.

Modification:

The POM-s are configured to put the correct module names to the manifest.

Result:

Fixes #7218.
2017-11-29 11:50:24 +01:00
Norman Maurer
188ea59c9d [maven-release-plugin] prepare for next development iteration 2017-11-08 22:36:53 +00:00
Norman Maurer
812354cf1f [maven-release-plugin] prepare release netty-4.1.17.Final 2017-11-08 22:36:33 +00:00
Norman Maurer
e7f02b1dc0 Set readPending to false when EOF is detected while issue an read
Motivation:

We need to set readPending to false when we detect a EOF while issue a read as otherwise we may not unregister from the Selector / Epoll / KQueue and so keep on receving wakeups.

The important bit is that we may even get a wakeup for a read event but will still will only be able to read 0 bytes from the socket, so we need to be very careful when we clear the readPending. This can happen because we generally using edge-triggered mode for our native transports and because of the nature of edge-triggered we may schedule an read event just to find out there is nothing left to read atm (because we completely drained the socket on the previous read).

Modifications:

Set readPending to false when EOF is detected.

Result:

Fixes [#7255].
2017-11-06 15:44:36 -08:00
Norman Maurer
bcad9dbf97 Revert "Set readPending to false when ever a read is done"
This reverts commit 413c7c2cd8 as it introduced an regression when edge-triggered mode is used which is true for our native transports by default. With 413c7c2cd8 included it was possible that we set readPending to false by mistake even if we would be interested in read more.
2017-11-06 09:21:42 -08:00
Scott Mitchell
413c7c2cd8 Set readPending to false when ever a read is done
Motivation:
readPending is currently only set to false if data is delivered to the application, however this may result in duplicate events being received from the selector in the event that the socket was closed.

Modifications:
- We should set readPending to false before each read attempt for all
transports besides NIO.
- Based upon the Javadocs it is possible that NIO may have spurious
wakeups [1]. In this case we should be more cautious and only set
readPending to false if data was actually read.

[1] https://docs.oracle.com/javase/7/docs/api/java/nio/channels/SelectionKey.html
That a selection key's ready set indicates that its channel is ready for some operation category is a hint, but not a guarantee, that an operation in such a category may be performed by a thread without causing the thread to block.

Result:
Notification from the selector (or simulated events from kqueue/epoll ET) in the event of socket closure.
Fixes https://github.com/netty/netty/issues/7255
2017-10-25 08:25:54 -07:00
Idel Pivnitskiy
50a067a8f7 Make methods 'static' where it possible
Motivation:

Even if it's a super micro-optimization (most JVM could optimize such
 cases in runtime), in theory (and according to some perf tests) it
 may help a bit. It also makes a code more clear and allows you to
 access such methods in the test scope directly, without instance of
 the class.

Modifications:

Add 'static' modifier for all methods, where it possible. Mostly in
test scope.

Result:

Cleaner code with proper 'static' modifiers.
2017-10-21 14:59:26 +02:00
Norman Maurer
9bcf31977c Fail the connectPromise with the correct exception if the connection is refused when using the native kqueue transport.
Motivation:

Due a bug we happen to sometimes fail the connectPromise with a ClosedChannelException when using the kqueue transport and the remote peer refuses the connection. We need to ensure we fail it with the correct exception.

Modifications:

Call finishConnect() before calling close() to ensure we preserve the correct exception.

Result:

KQueueSocketConnectionAttemptTest.testConnectionRefused will pass always on macOS.
2017-10-07 21:33:26 +02:00
Carl Mastrangelo
d3ca087f6b Propagate all exceptions when loading native code
Motivation:
There are 2 motivations, the first depends on the second:

Loading Netty Epoll statically stopped working in 4.1.16, due to
`Native` always loading the arch specific shared object.  In a
static binary, there is no arch specific SO.

Second, there are a ton of exceptions that can happen when loading
a native library.  When loading native code, Netty tries a bunch of
different paths but a failure in any given may not be fatal.

Additionally: turning on debug logging is not always feasible so
exceptions get silently swallowed.

Modifications:

* Change Epoll and Kqueue to try the static load second
* Modify NativeLibraryLoader to record all the locations where
  exceptions occur.
* Attempt to use `addSuppressed` from Java 7 if available.

Alternatives Considered:

An alternative would be to record log messages at each failure.  If
all load attempts fail, the log messages are printed as warning,
else as debug. The problem with this is there is no `LogRecord` to
create like in java.util.logging.  Buffering the args to
logger.log() at the end of the method loses the call site, and
changes the order of events to be confusing.

Another alternative is to teach NativeLibraryLoader about loading
the SO first, and then the static version.  This would consolidate
the code fore Epoll, Kqueue, and TCNative.   I think this is the
long term better option, but this PR is changing a lot already.
Someone else can take a crack at it later

Results:
Epoll Still Loads and easier debugging.
2017-10-04 08:45:27 +02:00
Norman Maurer
625a7426cd [maven-release-plugin] prepare for next development iteration 2017-09-25 06:12:32 +02:00
Norman Maurer
f57d8f00e1 [maven-release-plugin] prepare release netty-4.1.16.Final 2017-09-25 06:12:16 +02:00
Norman Maurer
aa8bdb5d6b Fix assertion error when closing / shutdown native channel and SO_LINGER is set.
Motivation:

When SO_LINGER is used we run doClose() on the GlobalEventExecutor by default so we need to ensure we schedule all code that needs to be run on the EventLoop on the EventLoop in doClose. Beside this there are also threading issues when calling shutdownOutput(...)

Modifications:

- Schedule removal from EventLoop to the EventLoop
- Correctly handle shutdownOutput and shutdown in respect with threading-model
- Add unit tests

Result:

Fixes [#7159].
2017-09-18 14:46:37 -07:00
Norman Maurer
426938307d Use the correct osname in the Bundle-NativeCode declaration.
Motivation:

We need to ensure we use the correct osname in the Bundle-NativeCode declaration as declared in:

https://www.osgi.org/developer/specifications/reference/

Modifications:

Update osname to match the spec.

Result:

Correct Bundle-NativeCode entry in the MANIFEST
2017-09-14 08:26:49 -07:00
Norman Maurer
0fffc844d6 Only load native transport if running architecture match the compiled library architecture.
Motivation:

We should only try to load the native artifacts if the architecture we are currently running on is the same as the one the native libraries were compiled for.

Modifications:

Include architecture in native lib name and append the current arch when trying to load these. This will fail then if its not the same as the arch of the compiled arch.

Result:

Fixes [#7150].
2017-09-04 13:34:55 +02:00
Carl Mastrangelo
c891c9c13f Include more detail why Unsafe is not available
Motivation:
PD and PD0 Both try to find and use Unsafe.  If unavailable, they
try to log why and continue on.  However, it is not always east to
enable this logging.  Chaining exceptions together is much easier
to reach, and the original exception is relevant when Unsafe is
needed.

Modifications:
* Make PD log why PD0 could not be loaded with a trace level log
* Make PD0 remember why Unsafe wasn't available
* Expose unavailability cause through PD for higher level use.
* Make Epoll and KQueue include the reason when failing

Result:
Easier debugging in hard to reconfigure environments
2017-08-29 22:02:06 +02:00
Scott Mitchell
89ecb4b4a4 AutoClose behavior may infinite loop
Motivation:
If AutoClose is false and there is a IoException then AbstractChannel will not close the channel but instead just fail flushed element in the ChannelOutboundBuffer. AbstractChannel also notifies of writability changes, which may lead to an infinite loop if the peer has closed its read side of the socket because we will keep accepting more data but continuously fail because the peer isn't accepting writes.

Modifications:
- If the transport throws on a write we should acknowledge that the output side of the channel has been shutdown and cleanup. If the channel can't accept more data because it is full, and still healthy it is not expected to throw. However if the channel is not healthy it will throw and is not expected to accept any more writes. In this case we should shutdown the output for Channels that support this feature and otherwise just close.
- Connection-less protocols like UDP can remain the same because the channel may disconnected temporarily.
- Make sure AbstractUnsafe#shutdownOutput is called because the shutdown on the socket may throw an exception.

Result:
More correct handling of write failure when AutoClose is false.
2017-08-25 21:01:41 -07:00
Norman Maurer
b967805f32 [maven-release-plugin] prepare for next development iteration 2017-08-24 15:38:22 +02:00
Norman Maurer
da8e010a42 [maven-release-plugin] prepare release netty-4.1.15.Final 2017-08-24 15:37:59 +02:00
Carl Mastrangelo
7f1051b6ca Include JNIEXPORT on exported symbols
Motivation:
As noticed in https://stackoverflow.com/questions/45700277/
compilation can fail if the definition of a method doesn't
match the declaration.  It's easy enough to add this in, and make
it easy to compile.

Modifications:
Add JNIEXPORT to the entry points.

* On Windows this adds: `__declspec(dllexport)`
* On Mac this adds: `__attribute__((visibility("default")))`
* On Linux (GCC 4.2+) this adds: ` __attribute__((visibility("default")))`
* On other it doesn't add anything.

Result:
Easier compilation
2017-08-18 17:34:48 -07:00
Scott Mitchell
fe2dd973e9 Unify KQueue and Epoll wait timeout approach
Motivation:
KQueueEventLoop and EpollEventLoop implement different approaches to applying a timeout of their respective poll calls. Epoll attempts to ensure the desired timeout is satisfied at the java layer and at the JNI layer, but it should be sufficient to account for spurious wakups at the JNI layer. Epoll timeout granularity is also limited to milliseconds which may be too large for some latency sensitive applications.

Modifications:
- Make EpollEventLoop wait method look like KQueueEventLoop
- Epoll should support a finer timeout granularity via timerfd_create. We can hide most of these details behind the epollWait0 JNI call to avoid crossing additional JNI boundaries.

Result:
More consistent timeout approach between KQueue and Epoll.
2017-08-18 13:09:02 -07:00
Scott Mitchell
1d7c3fb7ee KQueue detect peer close without EVFILT_READ
Motivation:
The EPOLL transport uses EPOLLRDHUP to detect when the peer closes the write side of the socket. Currently KQueue is not able to mimic this behavior and the only way to detect if the peer has closed is to read. It may not always be appropriate to read for backpressure and other reasons at the application level.

Modifications:
- Support EVFILT_SOCK filter which provides notification when the peer closes the socket

Result:
KQueue transport has more consistent behavior with Epoll transport for detecting peer closure.
2017-08-18 11:00:18 -07:00
Carl Mastrangelo
e4af881bdb Do not define JNI_OnLoad when not dynamic
Motivation:
Due to an oversight (by myself), linking two JNI modules with
duplicate symbols fails in linking.  This only seems to happen
some of the time (the behavior seems to be different between GCC
and Clang toolchains).  For instance, including both netty tcnative
and netty epoll fails to link because of duplicate JNI_OnLoad
symobols.

Modification:
Do not define the JNI_OnLoad and JNI_OnUnload symbols when
compiling for static linkage, as indicated by the NETTY_BUILD_STATIC
preprocessor define.  They are never directly called when
statically linked.

Result:
Able to statically compile epoll and tcnative code into a single
binary.
2017-08-18 09:20:58 +02:00
Norman Maurer
19dcb15062 Use underscore in native library names for consistency.
Motivation:

At the moment we try to load the library using multiple names which includes names using - but also _ . We should just use _ all the time.

Modifications:

Replace - with _

Result:

Fixes [#7069]
2017-08-15 06:02:00 +02:00
Scott Mitchell
237a4da1b7 Shutting down the outbound side of the channel should not accept future writes
Motivation:
Implementations of DuplexChannel delegate the shutdownOutput to the underlying transport, but do not take any action on the ChannelOutboundBuffer. In the event of a write failure due to the underlying transport failing and application may attempt to shutdown the output and allow the read side the transport to finish and detect the close. However this may result in an issue where writes are failed, this generates a writability change, we continue to write more data, and this may lead to another writability change, and this loop may continue. Shutting down the output should fail all pending writes and not allow any future writes to avoid this scenario.

Modifications:
- Implementations of DuplexChannel should null out the ChannelOutboundBuffer and fail all pending writes

Result:
More controlled sequencing for shutting down the output side of a channel.
2017-08-04 10:59:57 -07:00
Norman Maurer
4bb89dcc54 Correctly handle connect/disconnect in EpollDatagramChannel / KQueueDatagramChannel
Motivation:

We did not correctly handle connect() and disconnect() in EpollDatagramChannel / KQueueDatagramChannel and so the behavior was different compared to NioDatagramChannel.

Modifications:

- Correct implement connect and disconnect methods
- Share connect and related code
- Add tests

Result:

EpollDatagramChannel / KQueueDatagramChannel also supports correctly connect() and disconnect() methods.
2017-08-04 09:22:53 +02:00
Norman Maurer
52f384b37f [maven-release-plugin] prepare for next development iteration 2017-08-02 12:55:10 +00:00
Norman Maurer
8cc1071881 [maven-release-plugin] prepare release netty-4.1.14.Final 2017-08-02 12:54:51 +00:00
Carl Mastrangelo
d8f4547f5c Unify {Epoll,KQueue}EventLoopGroup initialization.
Motivation:
`Epoll.ensureAvailability()` is called multiple times, once in
static initialization and in a couple of the constructors.  This is
redundant and confusing to read.

Modifications:
Move `Epoll.ensureAvailability()` call into an instance initializer
and remove all other references.  This ensures that every EELG
checks availability, while still delaying the check until
construction.  This pattern is used when there are multiple ctors,
as in this class.

Result:
Easier to read code.
2017-07-24 20:14:54 +02:00
Norman Maurer
3cdff36821 Update tests to not use TestUtils.getFreePort() and so ensure we not try to use a port that is used by the system in the meantime.
Motivation:

We should not try to detect a free port in tests put just use 0 when bind so there is no race in which the system my bind something to the port we choosen before.

Modifications:

- Remove the usage of TestUtils.getFreePort() in the testsuite
- Remove hack to workaround bind errors which will not happen anymore now

Result:

Less flacky tests.
2017-07-20 08:25:37 +02:00
Scott Mitchell
7cfe416182 Use unbounded queues from JCTools 2.0.2
Motivation:
JCTools 2.0.2 provides an unbounded MPSC linked queue. Before we shaded JCTools we had our own unbounded MPSC linked queue and used it in various places but gave this up because there was no public equivalent available in JCTools at the time.

Modifications:
- Use JCTool's MPSC linked queue when no upper bound is specified

Result:
Fixes https://github.com/netty/netty/issues/5951
2017-07-10 12:32:15 -07:00