Bug 222411 – WebGL context count is not limited for GPU process

• Status: RESOLVED
• Resolution: FIXED
• Component: WebGL

[Kimmo Kinnunen]

WebGL context count is not limited for GPU process

Without GPU process, we have 20 context limit per web process.
With GPU process, we don't have any limit.


webgl/many-contexts-access-after-loss.html [ Failure ]
webgl/max-active-contexts-console-warning.html [ Failure ]
webgl/max-active-contexts-gc.html [ Failure ]
webgl/max-active-contexts-oldest-context-lost.html [ Failure ]
webgl/max-active-contexts-webglcontextlost-prevent-default.html [ Timeout ]

[Radar WebKit Bug Importer]

<rdar://problem/75025960>

[Kimmo Kinnunen]

Created attachment 453597 [details]
Patch

[Kimmo Kinnunen]

Created attachment 453599 [details]
Patch

[Kimmo Kinnunen]

Created attachment 453601 [details]
Patch

[Kimmo Kinnunen]

Created attachment 453616 [details]
Patch

[Kenneth Russell]

Comment on attachment 453616 [details]
Patch

Looks great. r+

[Kimmo Kinnunen]

Created attachment 453714 [details]
Patch

[Kimmo Kinnunen]

Created attachment 453716 [details]
Patch for landing

[Kimmo Kinnunen]

*** Bug 236964 has been marked as a duplicate of this bug. ***

[Darin Adler]

Comment on attachment 453714 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=453714&action=review

> Source/WebCore/html/canvas/WebGLRenderingContextBase.cpp:817
> +        auto it = contexts.begin();
> +        auto* earliest = *it;
> +        for (++it; it != contexts.end(); ++it) {
> +            if (earliest->activeOrdinal() > (*it)->activeOrdinal())
> +                earliest = *it;
> +        }

I might have written this with a modern for loop even though the loop is less tight:

    WebGLRenderingContextBase* earliest = nullptr;
    for (auto& context : contexts) {
        if (!earliest || earliest->activeOrdinal() > context.activeOrdinal())
            earliest = &context;
    }

Or using an algorithm:

    auto* earliest = *std::min_element(contexts.begin(), contexts.end(), [] (auto& a, auto& b) {
        return a.activeOrdinal() > b.activeOrdinal();
    });

Or some day (not now):

    auto* earliest = std::ranges::min_element(contexts, [] (auto& a, auto& b) {
        return a.activeOrdinal() > b.activeOrdinal();
    });

I may have the lambda backwards, not sure, so please don’t just paste.

[EWS]

Committed r290816 (248052@main): <https://commits.webkit.org/248052@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 453716 [details].

[Kimmo Kinnunen]

(In reply to Darin Adler from comment #10)
> Or using an algorithm:
> 
>     auto* earliest = *std::min_element(contexts.begin(), contexts.end(), []
> (auto& a, auto& b) {
>         return a.activeOrdinal() > b.activeOrdinal();
>     });
> 


Thanks for the suggestion, bug 237464 tracks this.