Add a command line option (-n) to use native threading, for testing.

I added this to test the impact of green threading.

src/components/embedding/core.rs

@@ -59,6 +59,7 @@ pub extern "C" fn cef_run_message_loop() {
         headless: false,
         hard_fail: false,
         bubble_widths_separately: false,
+        native_threading: false
     };
     native::start(0, 0 as **u8, proc() {
        servo::run(opts);

src/components/main/servo.rs

@@ -51,23 +51,15 @@ extern crate core_graphics;
 #[cfg(target_os="macos")]
 extern crate core_text;
 
-#[cfg(not(test))]
 use compositing::{CompositorChan, CompositorTask};
-#[cfg(not(test))]
 use constellation::Constellation;
-#[cfg(not(test))]
 use servo_msg::constellation_msg::{ConstellationChan, InitLoadUrlMsg};
 
-#[cfg(not(test))]
 use servo_net::image_cache_task::{ImageCacheTask, SyncImageCacheTask};
-#[cfg(not(test))]
 use servo_net::resource_task::ResourceTask;
-#[cfg(not(test))]
 use servo_util::time::Profiler;
 
-#[cfg(not(test))]
 use servo_util::opts;
-#[cfg(not(test))]
 use servo_util::url::parse_url;
 
 
@@ -75,9 +67,7 @@ use servo_util::url::parse_url;
 use std::os;
 #[cfg(not(test), target_os="android")]
 use std::str;
-#[cfg(not(test))]
 use std::task::TaskOpts;
-#[cfg(not(test))]
 use url::Url;
 
 
@@ -161,11 +151,41 @@ pub extern "C" fn android_start(argc: int, argv: **u8) -> int {
     })
 }
 
-#[cfg(not(test))]
+fn spawn_main(opts: opts::Opts,
+              compositor_port: Receiver<compositing::Msg>,
+              profiler_chan: servo_util::time::ProfilerChan,
+              result_port: Receiver<ConstellationChan>,
+              p: proc(): Send) {
+    if !opts.native_threading {
+        let mut pool_config = green::PoolConfig::new();
+        pool_config.event_loop_factory = rustuv::event_loop;
+        let mut pool = green::SchedPool::new(pool_config);
+
+        pool.spawn(TaskOpts::new(), p);
+
+        let constellation_chan = result_port.recv();
+
+        debug!("preparing to enter main loop");
+        CompositorTask::create(opts,
+                               compositor_port,
+                               constellation_chan,
+                               profiler_chan);
+
+        pool.shutdown();
+
+    } else {
+        native::task::spawn(p);
+        let constellation_chan = result_port.recv();
+
+        debug!("preparing to enter main loop");
+        CompositorTask::create(opts,
+                               compositor_port,
+                               constellation_chan,
+                               profiler_chan);
+    }
+}
+
 pub fn run(opts: opts::Opts) {
-    let mut pool_config = green::PoolConfig::new();
-    pool_config.event_loop_factory = rustuv::event_loop;
-    let mut pool = green::SchedPool::new(pool_config);
 
     let (compositor_port, compositor_chan) = CompositorChan::new();
     let profiler_chan = Profiler::create(opts.profiler_period);
@@ -174,7 +194,7 @@ pub fn run(opts: opts::Opts) {
     let profiler_chan_clone = profiler_chan.clone();
 
     let (result_chan, result_port) = channel();
-    pool.spawn(TaskOpts::new(), proc() {
+    spawn_main(opts.clone(), compositor_port, profiler_chan, result_port, proc() {
         let opts = &opts_clone;
         // Create a Servo instance.
         let resource_task = ResourceTask();
@@ -210,15 +230,5 @@ pub fn run(opts: opts::Opts) {
         // Send the constallation Chan as the result
         result_chan.send(constellation_chan);
     });
-
-    let constellation_chan = result_port.recv();
-
-    debug!("preparing to enter main loop");
-    CompositorTask::create(opts,
-                           compositor_port,
-                           constellation_chan,
-                           profiler_chan);
-
-    pool.shutdown();
 }
 

src/components/util/opts.rs

@@ -61,6 +61,9 @@ pub struct Opts {
     /// may wish to turn this flag on in order to benchmark style recalculation against other
     /// browser engines.
     pub bubble_widths_separately: bool,
+
+    /// Use native threads instead of green threads
+    pub native_threading: bool
 }
 
 fn print_usage(app: &str, opts: &[getopts::OptGroup]) {
@@ -77,7 +80,7 @@ pub fn from_cmdline_args(args: &[String]) -> Option<Opts> {
     let app_name = args[0].to_str();
     let args = args.tail();
 
-    let opts = vec!(
+    let opts = vec![
         getopts::optflag("c", "cpu", "CPU rendering"),
         getopts::optopt("o", "output", "Output file", "output.png"),
         getopts::optopt("r", "rendering", "Rendering backend", "direct2d|core-graphics|core-graphics-accelerated|cairo|skia."),
@@ -90,8 +93,9 @@ pub fn from_cmdline_args(args: &[String]) -> Option<Opts> {
         getopts::optflag("z", "headless", "Headless mode"),
         getopts::optflag("f", "hard-fail", "Exit on task failure instead of displaying about:failure"),
         getopts::optflag("b", "bubble-widths", "Bubble intrinsic widths separately like other engines"),
+        getopts::optflag("n", "native-threading", "Use native threading instead of green threading"),
         getopts::optflag("h", "help", "Print this message")
-    );
+    ];
 
     let opt_match = match getopts::getopts(args, opts.as_slice()) {
         Ok(m) => m,
@@ -169,6 +173,8 @@ pub fn from_cmdline_args(args: &[String]) -> Option<Opts> {
         None => cmp::max(rt::default_sched_threads() * 3 / 4, 1),
     };
 
+    let native_threading = opt_match.opt_present("h") || opt_match.opt_present("help");
+
     Some(Opts {
         urls: urls,
         render_backend: render_backend,
@@ -183,5 +189,6 @@ pub fn from_cmdline_args(args: &[String]) -> Option<Opts> {
         headless: opt_match.opt_present("z"),
         hard_fail: opt_match.opt_present("f"),
         bubble_widths_separately: opt_match.opt_present("b"),
+        native_threading: native_threading
     })
 }