Default to nonblocking whenever possible

Ruby 3.0 began to set O_NONBLOCK by default for all IO, to allow more IO types to enlist in the new IO/fiber scheduling. JRuby has not previously defaulted to nonblock, but all IO operations against nonblock-compatible channels does use nonblocking semantics, so all we really need to align with CRuby is to just set them non-blocking at the NIO level on creation. We can only do this when the underlying channel supports nonblocking semantics, but this commit attempts to set such channels up properly. Part of scheduler work in #7459 and related issues.
jruby · Nov 21, 2022 · adc8055 · adc8055
1 parent f4a4c5e
commit adc8055
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diff --git a/core/src/main/java/org/jruby/RubyIO.java b/core/src/main/java/org/jruby/RubyIO.java
@@ -903,6 +903,15 @@ private IRubyObject initializeCommon(ThreadContext context, int fileno, IRubyObj
                     }
                 }
             }
+
+            // set to nonblocking if possible (Ruby 3.0 change for IO/fiber scheduling)
+            if (fd.chSelect != null) {
+                try {
+                    fd.chSelect.configureBlocking(false);
+                } catch (IOException ioe) {
+                    // ignore, can't set nonblocking
+                }
+            }
         } else {
             fd = runtime.getFilenoUtil().getWrapperFromFileno(fileno);
 
@@ -4147,6 +4156,7 @@ private void setupPopen(final Ruby runtime, ModeFlags modes, POpenProcess proces
             ChannelFD main = new ChannelFD(inChannel, runtime.getPosix(), runtime.getFilenoUtil());
 
             openFile.setFD(main);
+            openFile.setBlocking(runtime, false);
         }
 
         if (openFile.isWritable() && process.hasOutput()) {
@@ -4169,6 +4179,7 @@ private void setupPopen(final Ruby runtime, ModeFlags modes, POpenProcess proces
                 setInstanceVariable("@tied_io_for_writing", writeIO);
             } else {
                 openFile.setFD(pipe);
+                openFile.setBlocking(runtime, false);
             }
         }
     }

diff --git a/core/src/main/java/org/jruby/ext/socket/RubyBasicSocket.java b/core/src/main/java/org/jruby/ext/socket/RubyBasicSocket.java
@@ -889,6 +889,7 @@ protected void initSocket(ChannelFD fd) {
         MakeOpenFile();
 
         openFile.setFD(fd);
+        openFile.setBlocking(getRuntime(), false);
         openFile.setMode(OpenFile.READWRITE | OpenFile.SYNC);
 
         // see rsock_init_sock in MRI; sockets are initialized to binary

diff --git a/core/src/main/java/org/jruby/ext/socket/RubyUNIXSocket.java b/core/src/main/java/org/jruby/ext/socket/RubyUNIXSocket.java
@@ -384,6 +384,7 @@ protected void init_sock(Ruby runtime, Channel channel, String path) {
         ModeFlags modes = newModeFlags(runtime, ModeFlags.RDWR);
 
         openFile.setFD(newChannelFD(runtime, channel));
+        openFile.setBlocking(runtime, false);
         openFile.setMode(modes.getOpenFileFlags());
         openFile.setSync(true);
         openFile.setPath(path);

diff --git a/core/src/main/java/org/jruby/util/io/OpenFile.java b/core/src/main/java/org/jruby/util/io/OpenFile.java
@@ -189,10 +189,18 @@ public boolean IS_PREP_STDIO() {
 
     public void setFD(ChannelFD fd) {
         this.fd = fd;
+        updateBlockingFromFD(fd);
     }
 
     public void setChannel(Channel fd) {
         this.fd = new ChannelFD(fd, runtime.getPosix(), runtime.getFilenoUtil());
+        updateBlockingFromFD(this.fd);
+    }
+
+    private void updateBlockingFromFD(ChannelFD fd) {
+        if (fd.chSelect != null ) {
+            this.nonblock = !fd.chSelect.isBlocking();
+        }
     }
 
     public int getMode() {