Auto merge of #10329 - Manishearth:skip-backtrace, r=asajeffrey

Skip printing the backtrace for RecvError/SendError

We currently get tons of useless backtraces clogging up the output when we have a panic cascade. This adds a handler that outputs a single line when a thread panics due to a sender or receiver hanging up, since this is almost always due to a panic cascade.

We could add a commandline arg that gets us back the old behavior, though I'm not sure if this is necessary.

r? @asajeffrey

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This commit is contained in:
bors-servo 2016-04-05 13:02:01 +05:30
commit 05a4dcdc3b
3 changed files with 47 additions and 1 deletions

View file

@ -9,6 +9,7 @@
#![cfg_attr(feature = "non-geckolib", feature(decode_utf16))]
#![feature(optin_builtin_traits)]
#![feature(plugin)]
#![feature(panic_handler)]
#![feature(reflect_marker)]
#![feature(step_by)]

View file

@ -198,6 +198,9 @@ pub struct Opts {
// Which rendering API to use.
pub render_api: RenderApi,
// don't skip any backtraces on panic
pub full_backtraces: bool,
}
fn print_usage(app: &str, opts: &Options) {
@ -285,6 +288,9 @@ pub struct DebugOptions {
/// Use multisample antialiasing in WebRender.
pub use_msaa: bool,
// don't skip any backtraces on panic
pub full_backtraces: bool,
}
@ -319,6 +325,7 @@ impl DebugOptions {
"disable-vsync" => debug_options.disable_vsync = true,
"wr-stats" => debug_options.webrender_stats = true,
"msaa" => debug_options.use_msaa = true,
"full-backtraces" => debug_options.full_backtraces = true,
"" => {},
_ => return Err(option)
};
@ -365,6 +372,7 @@ pub fn print_debug_usage(app: &str) -> ! {
"Disable vsync mode in the compositor to allow profiling at more than monitor refresh rate");
print_option("wr-stats", "Show WebRender profiler on screen.");
print_option("msaa", "Use multisample antialiasing in WebRender.");
print_option("full-backtraces", "Print full backtraces for all errors");
println!("");
@ -506,6 +514,7 @@ pub fn default_opts() -> Opts {
use_msaa: false,
render_api: DEFAULT_RENDER_API,
profile_dir: None,
full_backtraces: false,
}
}
@ -791,6 +800,7 @@ pub fn from_cmdline_args(args: &[String]) -> ArgumentParsingResult {
webrender_stats: debug_options.webrender_stats,
use_msaa: debug_options.use_msaa,
profile_dir: opt_match.opt_str("profile-dir"),
full_backtraces: debug_options.full_backtraces,
};
set_defaults(opts);

View file

@ -3,8 +3,11 @@
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use ipc_channel::ipc::IpcSender;
use opts;
use serde::Serialize;
use std::borrow::ToOwned;
use std::io::{Write, stderr};
use std::panic::{PanicInfo, take_handler, set_handler};
use std::sync::mpsc::Sender;
use std::thread;
use std::thread::Builder;
@ -14,7 +17,39 @@ pub fn spawn_named<F>(name: String, f: F)
where F: FnOnce() + Send + 'static
{
let builder = thread::Builder::new().name(name);
builder.spawn(f).unwrap();
if opts::get().full_backtraces {
builder.spawn(f).unwrap();
return;
}
let f_with_handler = move || {
let hook = take_handler();
let new_handler = move |info: &PanicInfo| {
let payload = info.payload();
if let Some(s) = payload.downcast_ref::<String>() {
if s.contains("SendError") {
let err = stderr();
let _ = write!(err.lock(), "Thread \"{}\" panicked with an unwrap of \
`SendError` (backtrace skipped)\n",
thread::current().name().unwrap_or("<unknown thread>"));
return;
} else if s.contains("RecvError") {
let err = stderr();
let _ = write!(err.lock(), "Thread \"{}\" panicked with an unwrap of \
`RecvError` (backtrace skipped)\n",
thread::current().name().unwrap_or("<unknown thread>"));
return;
}
}
hook(&info);
};
set_handler(new_handler);
f();
};
builder.spawn(f_with_handler).unwrap();
}
/// An abstraction over `Sender<T>` and `IpcSender<T>`, for use in