When rendering a page containing an iframe, layout 2020
creates parallel 'Layout' threads which share workers
in the stylo thread pool.
Because of the way the 'StyleSharingCache' is designed
using TLS for storage of the LRU cache, this leads to
a double borrow of the cache when both layout threads
run concurrently.
More details about the issue can be found here:
https://gist.github.com/mukilan/ed57eb61b83237a05fbf6360ec5e33b0
This PR is a workaround until we find a more elegant/optimal
design that also can work for gecko. The fix for now is
simply to not allow multiple layouts in parallel.
Signed-off-by: Mukilan Thiyagarajan <me@mukilan.in>
The Linux kernel imposes a 15-byte limit on thread names[1]. This means
information that does not fit in this limit, e.g., the pipeline ID of
layout and script threads, is lost in a debugger and profiler (see the
first column of the table below).
This commit shortens the thread names used in Servo to maximize the
amount of information conveyed. It also rectifies some inconsistencies
in the names.
| Before | After |
|-------------------|-------------------|
| `BluetoothThread` | `Bluetooth` |
| `CanvasThread` | `Canvas` |
| `display alert d` | `AlertDialog` |
| `FontCacheThread` | `FontCache` |
| `GLPlayerThread` | `GLPlayer` |
| `HTML Parser` | `Parse:www.examp` |
| `LayoutThread Pi` | `Layout(1,1)` |
| `Memory profiler` | `MemoryProfiler` |
| `Memory profiler` | `MemoryProfTimer` |
| `OfflineAudioCon` | `OfflineACResolv` |
| `PullTimelineMar` | `PullTimelineDat` |
| `ScriptThread Pi` | `Script(1,1)` |
| `WebWorker for h` | `WW:www.example.` |
| `ServiceWorker f` | `SW:www.example.` |
| `ServiceWorkerMa` | `SvcWorkerManage` |
| `Time profiler t` | `TimeProfTimer` |
| `Time profiler` | `TimeProfiler` |
| `WebGL thread` | `WebGL` |
| `Choose a device` | `DevicePicker` |
| `Pick a file` | `FilePicker` |
| `Pick files` | `FilePicker` |
[1]: https://stackoverflow.com/questions/5026531/thread-name-longer-than-15-chars
Instead of per-document. This also allows to reuse this thread-pool if needed
for other stuff, like parallel CSS parsing (#22478), and to share more code with
Gecko, which is always nice.
2018-12-23 13:00:56 +01:00
Renamed from components/style/gecko/global_style_data.rs (Browse further)
