Move Servo IPC off UI thread

Root cause of the post-tab lag: the GPUI 16 ms timer was calling
`WebSurfaceRuntime::ensure_tab` and `tick` on the UI thread, and each
call did a synchronous `serde_json` write plus `read_line` against the
Servo sidecar over stdin/stdout. With even one visible tab, every
frame stalled on cross-process IPC.

Introduce `web_surface_worker.rs` — a per-profile worker thread that
owns the `ServoLiveClient`, drains a coalescing request queue
(latest Ensure/Poll per tab wins, no unbounded growth), and ships
results back through a `std::sync::mpsc` channel. `WebSurfaceRuntime`
now submits work non-blockingly and drains responses in `tick`; the
UI thread never blocks on the sidecar.

Adjacent in-flight cleanup riding along: hardware IOSurface
rendering-context completion (sidecar `live_protocol`,
`hardware_rendering_context`, GPUI BGRA surface shader), CSS viewport
size + device pixel ratio plumbing into `ServoLiveFrame`, and the
Send opt-ins for `CVPixelBuffer`-bearing types so frames can cross
the thread boundary.
This commit is contained in:
2026-05-15 16:41:40 -04:00
parent f4c650c4d8
commit 90c029eddb
29 changed files with 2113 additions and 496 deletions
+158 -3
View File
@@ -10,9 +10,10 @@ use std::{
use ely_domain::{ProfileId, SiteOrigin, SitePermissionFeature, TabId, UrlText};
use ely_servo_host::{
KeyboardTextRequest, MouseClickRequest, MouseDragRequest, NavigationRequest, PageZoomRequest,
PermissionDecision, PermissionRequest, ResizeRequest, ScreenshotRequest, ScrollRequest,
ServoHost, ServoHostError, ServoSurfaceSize, SoftwareServoHost, TouchTapRequest, WebViewState,
HidpiScaleRequest, KeyboardTextRequest, MouseClickRequest, MouseDragRequest, NavigationRequest,
PageZoomRequest, PermissionDecision, PermissionRequest, ResizeRequest, ScreenshotRequest,
ScrollRequest, ServoHost, ServoHostError, ServoSurfaceSize, SoftwareServoHost, TouchTapRequest,
WebViewState,
};
const MINIMUM_CONTENT_PIXELS: u64 = 1_000;
@@ -25,6 +26,7 @@ const PRD_SITE_COMPATIBILITY_CASES: &[PrdSiteCompatibilityCase] = &[
PrdSiteCompatibilityCase { url: "https://servo.org/", title_fragment: "Servo" },
];
const SOFTWARE_HOST_CHILD_ENV: &str = "ELY_SERVO_SOFTWARE_HOST_CHILD";
const DPR_VIEWPORT_CHILD_ENV: &str = "ELY_SERVO_DPR_VIEWPORT_CHILD";
const CLICK_PROBE_URL: &str = "data:text/html,%3C!doctype%20html%3E%3Ctitle%3EClick%20Probe%3C%2Ftitle%3E%3Cstyle%3Ebody%7Bmargin%3A0%3Bbackground%3A%23f7f7f7%3B%7Dbutton%7Bposition%3Aabsolute%3Bleft%3A80px%3Btop%3A80px%3Bwidth%3A220px%3Bheight%3A90px%3Bfont%3A28px%20sans-serif%3Bbackground%3A%23ffffff%3Bcolor%3A%23111111%3B%7D%3C%2Fstyle%3E%3Cbutton%20onclick%3D%22document.body.style.background%3D%27%230039ff%27%3Bdocument.title%3D%27Clicked%27%3Bthis.textContent%3D%27Clicked%27%3B%22%3ETap%3C%2Fbutton%3E";
const DRAG_PROBE_URL: &str = "data:text/html,%3C%21doctype%20html%3E%3Ctitle%3EDrag%20Probe%3C%2Ftitle%3E%3Cstyle%3Ebody%7Bmargin%3A0%3Bbackground%3A%23f7f7f7%3B%7Dbutton%7Bposition%3Aabsolute%3Bleft%3A80px%3Btop%3A80px%3Bwidth%3A220px%3Bheight%3A90px%3Bfont%3A28px%20sans-serif%3Bbackground%3A%23ffffff%3Bcolor%3A%23111111%3B%7D%3C%2Fstyle%3E%3Cbutton%20id%3Dbox%3EDrag%3C%2Fbutton%3E%3Cscript%3Elet%20dragging%3Dfalse%3Bconst%20box%3Ddocument.getElementById%28%27box%27%29%3BaddEventListener%28%27mousedown%27%2Cevent%3D%3E%7Bif%28event.target%3D%3D%3Dbox%29%7Bdragging%3Dtrue%3B%7D%7D%29%3BaddEventListener%28%27mousemove%27%2Cevent%3D%3E%7Bif%28dragging%26%26event.clientX%3E280%29%7Bdocument.body.style.background%3D%27%230039ff%27%3Bdocument.title%3D%27Dragged%27%3Bbox.textContent%3D%27Dragged%27%3B%7D%7D%29%3BaddEventListener%28%27mouseup%27%2C%28%29%3D%3E%7Bdragging%3Dfalse%3B%7D%29%3B%3C%2Fscript%3E";
const TOUCH_PROBE_URL: &str = "data:text/html,%3C%21doctype%20html%3E%3Ctitle%3ETouch%20Probe%3C%2Ftitle%3E%3Cstyle%3Ebody%7Bmargin%3A0%3Bbackground%3A%23f7f7f7%3B%7Dbutton%7Bposition%3Aabsolute%3Bleft%3A80px%3Btop%3A80px%3Bwidth%3A220px%3Bheight%3A90px%3Bfont%3A28px%20sans-serif%3Bbackground%3A%23ffffff%3Bcolor%3A%23111111%3Btouch-action%3Amanipulation%3B%7D%3C%2Fstyle%3E%3Cbutton%20ontouchstart%3D%22document.body.dataset.touch%3D%27start%27%3B%22%20onclick%3D%22document.body.style.background%3D%27%230039ff%27%3Bdocument.title%3D%27Touched%27%3Bthis.textContent%3D%27Touched%27%3B%22%3ETap%3C%2Fbutton%3E";
@@ -36,6 +38,13 @@ struct PrdSiteCompatibilityCase {
title_fragment: &'static str,
}
struct DprViewportCase {
physical_width: u32,
physical_height: u32,
dpr: f32,
expected_css_width: u32,
}
#[test]
fn manages_real_servo_webview_lifecycle() -> Result<(), Box<dyn Error>> {
if env::var_os(SOFTWARE_HOST_CHILD_ENV).is_none() {
@@ -67,6 +76,122 @@ fn run_isolated_software_host_lifecycle() -> Result<(), Box<dyn Error>> {
.into())
}
#[test]
fn first_navigation_preserves_dpr_for_css_viewport() -> Result<(), Box<dyn Error>> {
if env::var_os(DPR_VIEWPORT_CHILD_ENV).is_none() {
return run_isolated_dpr_viewport_test();
}
exercise_dpr_viewport_cases()
}
fn run_isolated_dpr_viewport_test() -> Result<(), Box<dyn Error>> {
let output = Command::new(env::current_exe()?)
.arg("--exact")
.arg("first_navigation_preserves_dpr_for_css_viewport")
.env(DPR_VIEWPORT_CHILD_ENV, "1")
.stdout(Stdio::piped())
.stderr(Stdio::piped())
.output()?;
if output.status.success() {
return Ok(());
}
Err(format!(
"isolated DPR viewport test failed\nstatus: {}\nstdout: {}\nstderr: {}",
output.status,
String::from_utf8_lossy(&output.stdout),
String::from_utf8_lossy(&output.stderr)
)
.into())
}
fn exercise_dpr_viewport_cases() -> Result<(), Box<dyn Error>> {
let mut host = SoftwareServoHost::new(ServoSurfaceSize::new(1, 1))?;
let profile_id = ProfileId::new();
let cases = [
DprViewportCase {
physical_width: 800,
physical_height: 600,
dpr: 1.0,
expected_css_width: 800,
},
DprViewportCase {
physical_width: 960,
physical_height: 640,
dpr: 2.0,
expected_css_width: 480,
},
DprViewportCase {
physical_width: 1250,
physical_height: 800,
dpr: 1.25,
expected_css_width: 1000,
},
DprViewportCase {
physical_width: 1440,
physical_height: 900,
dpr: 1.5,
expected_css_width: 960,
},
DprViewportCase {
physical_width: 1750,
physical_height: 1000,
dpr: 1.75,
expected_css_width: 1000,
},
DprViewportCase {
physical_width: 1500,
physical_height: 900,
dpr: 2.5,
expected_css_width: 600,
},
DprViewportCase {
physical_width: 2160,
physical_height: 1440,
dpr: 3.0,
expected_css_width: 720,
},
];
for case in cases {
let tab_id = TabId::new();
let webview_id = host.create_webview_with_size(
tab_id.clone(),
profile_id.clone(),
ServoSurfaceSize::new(case.physical_width, case.physical_height),
)?;
host.set_hidpi_scale(HidpiScaleRequest {
webview_id: webview_id.clone(),
scale_factor: case.dpr,
})?;
host.navigate(NavigationRequest {
webview_id: webview_id.clone(),
tab_id,
url: UrlText::parse(viewport_probe_url(case.expected_css_width + 1))?,
})?;
let snapshot = wait_for_rendered_webview(&mut host, &webview_id, None)?;
assert_eq!(snapshot.state(), &WebViewState::Complete, "snapshot: {snapshot:?}");
let frame = host.last_rendered_frame()?;
assert_eq!(frame.width(), case.physical_width, "DPR case frame width");
assert_eq!(frame.height(), case.physical_height, "DPR case frame height");
assert_eq!(
center_pixel_rgb(&frame),
[238, 32, 77],
"CSS viewport must equal physical width divided by DPR: physical={} dpr={} expected_css={}",
case.physical_width,
case.dpr,
case.expected_css_width,
);
host.close_webview(&webview_id);
}
Ok(())
}
fn exercise_real_servo_webview_lifecycle() -> Result<(), Box<dyn Error>> {
let mut host = SoftwareServoHost::new(ServoSurfaceSize::new(INITIAL_WIDTH, INITIAL_HEIGHT))?;
let tab_id = TabId::new();
@@ -340,3 +465,33 @@ fn assert_frame_has_dimensions_and_content(
assert!(frame.content_pixel_count() >= minimum_content_pixels, "{label}: {frame:?}");
assert_ne!(frame.sample_hash(), 0, "{label}: {frame:?}");
}
fn center_pixel_rgb(frame: &ely_servo_host::RenderedFrame) -> [u8; 3] {
let x = frame.width() / 2;
let y = frame.height() / 2;
let index = ((y * frame.width() + x) * 4) as usize;
let rgba = &frame.rgba_bytes()[index..index + 4];
[rgba[0], rgba[1], rgba[2]]
}
fn viewport_probe_url(min_width_threshold: u32) -> String {
let html = format!(
"<!doctype html><title>DPR Probe</title><style>\
html,body{{margin:0;width:100%;height:100%;background:rgb(238,32,77);}}\
@media (min-width:{min_width_threshold}px){{html,body{{background:rgb(0,57,255);}}}}\
</style>",
);
format!("data:text/html,{}", percent_encode_for_data_url(&html))
}
fn percent_encode_for_data_url(value: &str) -> String {
value
.bytes()
.map(|byte| match byte {
b'A'..=b'Z' | b'a'..=b'z' | b'0'..=b'9' | b'-' | b'_' | b'.' | b'~' => {
(byte as char).to_string()
}
_ => format!("%{byte:02X}"),
})
.collect()
}