489561 - nsPrincipal should cache nsIPrefBranch and codebase_principal_support pref

Status: RESOLVED FIXED

(Core :: Security: CAPS, defect)

Description

[Olli Pettay [:smaug][[e-mail]]]

nsPrincipal::CanEnableCapability is pretty expensive because it calls
do_GetService(NS_PREFSERVICE_CONTRACTID) and GetBoolPref

Comment 1

[Olli Pettay [:smaug][[e-mail]]]

Attachment: patch

This speeds up content JS DOM event dispatch nearly 10%.

Comment 2

[Daniel Veditz [:dveditz]]

Comment on attachment 381297 [details] [diff] [review]
patch

r/sr=dveditz

Comment 3

[Boris Zbarsky [:bzbarsky]]

This patch doesn't work right if you set the pref to true and then unset it.  It'l leave the static bool true.  You should be explicitly setting to false when the get fails.

Also, why check observer topic but not pref name?  I'd just assert both...

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

Ok, I'll fix those cases.

Comment 5

[Olli Pettay [:smaug][[e-mail]]]

Attachment: v2

Comment 6

[Boris Zbarsky [:bzbarsky]]

> +    if (prefBranch &&

I'd prefer "!prefBranch ||" here, so we fail safe.

Comment 7

[Olli Pettay [:smaug][[e-mail]]]

Attachment: v3

Comment 8

[Olli Pettay [:smaug][[e-mail]]]

http://hg.mozilla.org/mozilla-central/rev/5a34b38593e5