Up until now, Servo was using a very old version of time to get a
cross-process monotonic timestamp (using `time::precise_time_ns()`).
This change replaces the usage of old time with a new serializable
monotonic time called `CrossProcessInstant` and uses it where `u64`
timestamps were stored before. The standard library doesn't provide this
functionality because it isn't something you can do reliably on all
platforms. The idea is that we do our best and then fall back
gracefully.
This is a big change, because Servo was using `u64` timestamps all over
the place some as raw values taken from `time::precise_time_ns()` and
some as relative offsets from the "navigation start," which is a concept
similar to DOM's `timeOrigin` (but not exactly the same). It's very
difficult to fix this situation without fixing it everywhere as the
`Instant` concept is supposed to be opaque. The good thing is that this
change clears up all ambiguity when passing times as a `time::Duration`
is unit agnostic and a `CrossProcessInstant` represents an absolute
moment in time.
The `time` version of `Duration` is used because it can both be negative
and is also serializable.
Good things:
- No need too pass around `time` and `time_precise` any longer.
`CrossProcessInstant` is also precise and monotonic.
- The distinction between a time that is unset or at `0` (at some kind
of timer epoch) is now gone.
There still a lot of work to do to clean up timing, but this is the
first step. In general, I've tried to preserve existing behavior, even
when not spec compliant, as much as possible. I plan to submit followup
PRs fixing some of the issues I've noticed.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
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
Accept transfer argument for StructuredCloneData::write
Allow structured clone reads to return a boolean
Add Transferable trait
Add basic skeletons to MessagePort
Implement transfer and transfer-receiving steps on MessagePort
Use transfer and transfer_receive in StructuredClone callbacks
Implement MessageChannel
Freeze the array object for the MessageEvent ports attribute
Implement transfer argument on window.postMessage
Use ReentrantMutex instead for MessagePortInternal
Accept origin as a parameter in dispatch_jsval
Fix BorrowMut crash with pending_port_message
Detach port on closure and check for detached during transfer
Enable webmessaging tests
fix webidl
fix
Refactor `.sort_by()` calls to use `.partial_cmp()`
Changes the closures passed to `sort_by` in this file with a simpler, and more correct version.
Previously, potential NaNs in the array would float to the top. Either way, the program would crash, as the `get_statistics` function asserts the array it gets is sorted, which always fails with a NaN.
Because of that, this change should not affect functionality.
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- [ ] These changes fix #__ (github issue number if applicable).
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- [X] These changes do not require tests because statistics collected by --profile should not have NaN values in the first place.
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