Ensure that resized GL contexts do not destroy their resources while in use by WR.

8 files changed, 43 insertions, 23 deletions

diff --git a/Cargo.lock b/Cargo.lock
index c9d8a1282cf..1a0d1643205 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -417,7 +417,7 @@ dependencies = [
  "ipc-channel 0.11.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "offscreen_gl_context 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "offscreen_gl_context 0.22.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "pixels 0.0.1",
  "serde_bytes 0.10.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "servo_config 0.0.1",
@@ -436,7 +436,7 @@ dependencies = [
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "malloc_size_of 0.0.1",
  "malloc_size_of_derive 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "offscreen_gl_context 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "offscreen_gl_context 0.22.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "pixels 0.0.1",
  "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_bytes 0.10.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1466,7 +1466,7 @@ name = "gst-plugin"
 version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "byteorder 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "glib 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "glib-sys 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "gobject-subclass 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2201,7 +2201,7 @@ version = "0.1.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "adler32 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "byteorder 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc32fast 1.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -2832,7 +2832,7 @@ dependencies = [
 
 [[package]]
 name = "offscreen_gl_context"
-version = "0.21.1"
+version = "0.22.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cgl 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2895,8 +2895,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "osmesa-src"
-version = "0.1.1"
-source = "git+https://github.com/servo/osmesa-src#939207de2f4617cb958548490764f7380cf0c6e4"
+version = "0.1.0"
+source = "git+https://github.com/servo/osmesa-src#97f4613fd80eee153ab134dfe349777bc5a27bab"
 
 [[package]]
 name = "osmesa-sys"
@@ -3352,7 +3352,7 @@ dependencies = [
  "msg 0.0.1",
  "net_traits 0.0.1",
  "num-traits 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "offscreen_gl_context 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "offscreen_gl_context 0.22.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf 0.7.23 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf_codegen 0.7.23 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3548,7 +3548,7 @@ dependencies = [
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libservo 0.0.1",
  "log 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "osmesa-src 0.1.1 (git+https://github.com/servo/osmesa-src)",
+ "osmesa-src 0.1.0 (git+https://github.com/servo/osmesa-src)",
  "osmesa-sys 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "sig 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "tinyfiledialogs 3.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3968,7 +3968,6 @@ dependencies = [
  "bindgen 0.46.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
- "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam-channel 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.25.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding_rs 0.8.12 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -5164,13 +5163,13 @@ dependencies = [
 "checksum objc 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "5ffd1ab984e2a5ed8a222a6b567d38a69c1d04d64b19eb7c2b10794c6af9f76c"
 "checksum objc-foundation 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "1add1b659e36c9607c7aab864a76c7a4c2760cd0cd2e120f3fb8b952c7e22bf9"
 "checksum objc_id 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e4730aa1c64d722db45f7ccc4113a3e2c465d018de6db4d3e7dfe031e8c8a297"
-"checksum offscreen_gl_context 0.21.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5e86c90338962922a5f623128079b5c01d03784c8fd0809691f4eba233d69a1c"
+"checksum offscreen_gl_context 0.22.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2e41ac2a2751637c40a7daff7ac6783cff25a51cfb8cf06294c1ffcc56ecafd5"
 "checksum opaque-debug 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "51ecbcb821e1bd256d456fe858aaa7f380b63863eab2eb86eee1bd9f33dd6682"
 "checksum openssl 0.10.11 (registry+https://github.com/rust-lang/crates.io-index)" = "6c24d3508b4fb6da175c10baac54c578b33f09c89ae90c6fe9788b3b4768efdc"
 "checksum openssl-sys 0.9.35 (registry+https://github.com/rust-lang/crates.io-index)" = "912f301a749394e1025d9dcddef6106ddee9252620e6d0a0e5f8d0681de9b129"
 "checksum ordered-float 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e9a3c8db0fca1fdb34404f0b1286db252f23930b9f7a481e376c16c0d5c309d4"
 "checksum ordermap 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "a86ed3f5f244b372d6b1a00b72ef7f8876d0bc6a78a4c9985c53614041512063"
-"checksum osmesa-src 0.1.1 (git+https://github.com/servo/osmesa-src)" = "<none>"
+"checksum osmesa-src 0.1.0 (git+https://github.com/servo/osmesa-src)" = "<none>"
 "checksum osmesa-sys 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "88cfece6e95d2e717e0872a7f53a8684712ad13822a7979bc760b9c77ec0013b"
 "checksum ovr-mobile-sys 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a69b517feac6fc640f0679625defa0998bbcb32871a6901e63063c2abf9c4cbe"
 "checksum owning_ref 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "49a4b8ea2179e6a2e27411d3bca09ca6dd630821cf6894c6c7c8467a8ee7ef13"
diff --git a/components/canvas/Cargo.toml b/components/canvas/Cargo.toml
index fc519588339..37ee56d6e5a 100644
--- a/components/canvas/Cargo.toml
+++ b/components/canvas/Cargo.toml
@@ -26,7 +26,7 @@ half = "1"
 ipc-channel = "0.11"
 log = "0.4"
 num-traits = "0.2"
-offscreen_gl_context = {version = "0.21", features = ["serde", "osmesa"]}
+offscreen_gl_context = {version = "0.22", features = ["serde", "osmesa"]}
 pixels = {path = "../pixels"}
 serde_bytes = "0.10"
 servo_config = {path = "../config"}
diff --git a/components/canvas/gl_context.rs b/components/canvas/gl_context.rs
index 093d1837920..281c78b7f3b 100644
--- a/components/canvas/gl_context.rs
+++ b/components/canvas/gl_context.rs
@@ -8,7 +8,7 @@ use compositing::compositor_thread::{self, CompositorProxy};
 use euclid::Size2D;
 use gleam::gl;
 use offscreen_gl_context::{
-    ColorAttachmentType, GLContext, GLContextAttributes, GLContextDispatcher,
+    ColorAttachmentType, DrawBuffer, GLContext, GLContextAttributes, GLContextDispatcher,
 };
 use offscreen_gl_context::{GLLimits, GLVersion};
 use offscreen_gl_context::{NativeGLContext, NativeGLContextHandle, NativeGLContextMethods};
@@ -207,7 +207,7 @@ impl GLContextWrapper {
         }
     }
 
-    pub fn resize(&mut self, size: Size2D<u32>) -> Result<(), &'static str> {
+    pub fn resize(&mut self, size: Size2D<u32>) -> Result<DrawBuffer, &'static str> {
         match *self {
             GLContextWrapper::Native(ref mut ctx) => {
                 // FIXME(nox): Why are those i32 values?
diff --git a/components/canvas/webgl_thread.rs b/components/canvas/webgl_thread.rs
index 93134dd7487..2add67cfd2a 100644
--- a/components/canvas/webgl_thread.rs
+++ b/components/canvas/webgl_thread.rs
@@ -9,7 +9,9 @@ use euclid::Size2D;
 use fnv::FnvHashMap;
 use gleam::gl;
 use half::f16;
-use offscreen_gl_context::{GLContext, GLContextAttributes, GLLimits, NativeGLContextMethods};
+use offscreen_gl_context::{
+    DrawBuffer, GLContext, GLContextAttributes, GLLimits, NativeGLContextMethods,
+};
 use pixels::{self, PixelFormat};
 use std::borrow::Cow;
 use std::thread;
@@ -228,6 +230,7 @@ impl<VR: WebVRRenderHandler + 'static> WebGLThread<VR> {
             Self::make_current_if_needed(context_id, &self.contexts, &mut self.bound_context_id)
                 .expect("WebGLContext not found in a WebGLMsg::Lock message");
         let info = self.cached_context_info.get_mut(&context_id).unwrap();
+        info.render_state = ContextRenderState::Locked(None);
         // Insert a OpenGL Fence sync object that sends a signal when all the WebGL commands are finished.
         // The related gl().wait_sync call is performed in the WR thread. See WebGLExternalImageApi for mor details.
         let gl_sync = data.ctx.gl().fence_sync(gl::SYNC_GPU_COMMANDS_COMPLETE, 0);
@@ -247,6 +250,7 @@ impl<VR: WebVRRenderHandler + 'static> WebGLThread<VR> {
             Self::make_current_if_needed(context_id, &self.contexts, &mut self.bound_context_id)
                 .expect("WebGLContext not found in a WebGLMsg::Unlock message");
         let info = self.cached_context_info.get_mut(&context_id).unwrap();
+        info.render_state = ContextRenderState::Unlocked;
         if let Some(gl_sync) = info.gl_sync.take() {
             // Release the GLSync object.
             data.ctx.gl().delete_sync(gl_sync);
@@ -299,6 +303,7 @@ impl<VR: WebVRRenderHandler + 'static> WebGLThread<VR> {
                 image_key: None,
                 share_mode,
                 gl_sync: None,
+                render_state: ContextRenderState::Unlocked,
             },
         );
 
@@ -319,9 +324,19 @@ impl<VR: WebVRRenderHandler + 'static> WebGLThread<VR> {
         )
         .expect("Missing WebGL context!");
         match data.ctx.resize(size) {
-            Ok(_) => {
+            Ok(old_draw_buffer) => {
                 let (real_size, texture_id, _) = data.ctx.get_info();
                 let info = self.cached_context_info.get_mut(&context_id).unwrap();
+                if let ContextRenderState::Locked(ref mut in_use) = info.render_state {
+                    // If there's already an outdated draw buffer present, we can ignore
+                    // the newly resized one since it's not in use by the renderer.
+                    if in_use.is_none() {
+                        // We're resizing the context while WR is actively rendering
+                        // it, so we need to retain the GL resources until WR is
+                        // finished with them.
+                        *in_use = Some(old_draw_buffer);
+                    }
+                }
                 // Update webgl texture size. Texture id may change too.
                 info.texture_id = texture_id;
                 info.size = real_size;
@@ -682,6 +697,14 @@ impl<VR: WebVRRenderHandler + 'static> Drop for WebGLThread<VR> {
     }
 }
 
+enum ContextRenderState {
+    /// The context is not being actively rendered.
+    Unlocked,
+    /// The context is actively being rendered. If a DrawBuffer value is present,
+    /// it is outdated but in use as long as the context is locked.
+    Locked(Option<DrawBuffer>),
+}
+
 /// Helper struct to store cached WebGLContext information.
 struct WebGLContextInfo {
     /// Render to texture identifier used by the WebGLContext.
@@ -696,6 +719,8 @@ struct WebGLContextInfo {
     share_mode: WebGLContextShareMode,
     /// GLSync Object used for a correct synchronization with Webrender external image callbacks.
     gl_sync: Option<gl::GLsync>,
+    /// The status of this context with respect to external consumers.
+    render_state: ContextRenderState,
 }
 
 /// This trait is used as a bridge between the `WebGLThreads` implementation and
diff --git a/components/canvas_traits/Cargo.toml b/components/canvas_traits/Cargo.toml
index 1e7e17f8b9e..9d022072511 100644
--- a/components/canvas_traits/Cargo.toml
+++ b/components/canvas_traits/Cargo.toml
@@ -21,7 +21,7 @@ gleam = "0.6.7"
 lazy_static = "1"
 malloc_size_of = { path = "../malloc_size_of" }
 malloc_size_of_derive = "0.1"
-offscreen_gl_context = {version = "0.21", features = ["serde"]}
+offscreen_gl_context = {version = "0.22", features = ["serde"]}
 pixels = {path = "../pixels"}
 serde = "1.0"
 serde_bytes = "0.10"
diff --git a/components/script/Cargo.toml b/components/script/Cargo.toml
index e6cb81366d0..cae434ab7d4 100644
--- a/components/script/Cargo.toml
+++ b/components/script/Cargo.toml
@@ -77,7 +77,7 @@ mime_guess = "2.0.0-alpha.6"
 msg = {path = "../msg"}
 net_traits = {path = "../net_traits"}
 num-traits = "0.2"
-offscreen_gl_context = {version = "0.21", features = ["serde"]}
+offscreen_gl_context = {version = "0.22", features = ["serde"]}
 parking_lot = "0.6"
 phf = "0.7.18"
 pixels = {path = "../pixels"}
diff --git a/tests/wpt/webgl/meta/conformance/canvas/to-data-url-test.html.ini b/tests/wpt/webgl/meta/conformance/canvas/to-data-url-test.html.ini
index b3727b5f4bc..ed8c57315e8 100644
--- a/tests/wpt/webgl/meta/conformance/canvas/to-data-url-test.html.ini
+++ b/tests/wpt/webgl/meta/conformance/canvas/to-data-url-test.html.ini
@@ -1,6 +1,4 @@
 [to-data-url-test.html]
-  expected:
-    if os == "linux": CRASH
   [WebGL test #12: should be 0,255,0,255\nat (0, 0) expected: 0,255,0,255 was 255,0,0,255]
     expected: FAIL
 
diff --git a/tests/wpt/webgl/meta/conformance/textures/misc/texture-size-cube-maps.html.ini b/tests/wpt/webgl/meta/conformance/textures/misc/texture-size-cube-maps.html.ini
index c52e4f589ea..d12c43168d2 100644
--- a/tests/wpt/webgl/meta/conformance/textures/misc/texture-size-cube-maps.html.ini
+++ b/tests/wpt/webgl/meta/conformance/textures/misc/texture-size-cube-maps.html.ini
@@ -1,6 +1,4 @@
 [texture-size-cube-maps.html]
-  expected:
-    if os == "linux": CRASH
   [WebGL test #87: 0, 0, 2, 1 should be green\nat (0, 0) expected: 0,255,0,255 was 0,255,255,255]
     expected: FAIL