Bug 161859 – Link loader should use FetchOptions::mode according its crossOrigin attribute

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[youenn fablet]

This will allow actual reuse of resources now that the cache is handling resource origin and CORS mode.

[youenn fablet]

Created attachment 288566 [details]
Patch

[youenn fablet]

Created attachment 289039 [details]
Patch for landing

[WebKit Commit Bot]

Comment on attachment 289039 [details]
Patch for landing

Clearing flags on attachment: 289039

Committed r206010: <http://trac.webkit.org/changeset/206010>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Antti Koivisto]

Comment on attachment 289039 [details]
Patch for landing

View in context: https://bugs.webkit.org/attachment.cgi?id=289039&action=review

> Source/WebCore/loader/cache/CachedCSSStyleSheet.cpp:99
> +    m_parsedStyleSheetCache = sheet.m_parsedStyleSheetCache;

This is not correct. It is not safe to have multiple cache clients for the same StyleSheetContents instance. This should make a copy() and call addedToMemoryCache() for it.

This is a probable cause for https://bugs.webkit.org/show_bug.cgi?id=163905

[youenn fablet]

Comment on attachment 289039 [details]
Patch for landing

View in context: https://bugs.webkit.org/attachment.cgi?id=289039&action=review

>> Source/WebCore/loader/cache/CachedCSSStyleSheet.cpp:99
>> +    m_parsedStyleSheetCache = sheet.m_parsedStyleSheetCache;
> 
> This is not correct. It is not safe to have multiple cache clients for the same StyleSheetContents instance. This should make a copy() and call addedToMemoryCache() for it.
> 
> This is a probable cause for https://bugs.webkit.org/show_bug.cgi?id=163905

I can prepare something along the lines you mention but I would be interested in further understanding the situation.
For instance, what is the reason of this multiple cache clients limitation? Can we remove it?

[Antti Koivisto]

> I can prepare something along the lines you mention but I would be
> interested in further understanding the situation.
> For instance, what is the reason of this multiple cache clients limitation?
> Can we remove it?

It might actually be just matter of replacing m_isInMemoryCache bit with m_isInMemoryCacheCount that gets incremented and decremented as needed.

The bit is used to figuring out if we need to make a copy of the stylesheet contents when it is mutated via API. See CSSStyleSheet::willMutateRules().

[Antti Koivisto]

m_inMemoryCacheCount