538450 - Make string atomization not require taking a runtime lock?

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Jeff Walden [:Waldo]]

Conceptually, it seems like it should be feasible to use a threadsafe hashtable to store atomized strings, where the pattern of js_AtomizeString would be probe, return if non-null, create the atomized string, insert with compare-and-swap with null and the atomized string, then return either the atomized string if the hash entry was changed from null or the existing atomization if the hash entry wasn't null.  Is it actually feasible?  Dunno, worth filing in any case.

Comment 1

[Tooru Fujisawa [:arai]]

once bug 1687973 is fixed, atomization doesn't happen off-main thread, and we don't need lock.

Comment 2

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 1: Remove Zone::{helperThreadUse_,helperThreadOwnerContext_}. r?jonco!

Bug 1687973 removed the remaining consumer of related methods.

• GCRuntime::setParallelAtomsAllocEnabled is removed in Part 2
• JSRuntime::numActiveHelperThreadZones is removed in Part 2
• GCRuntime::triggerFullGCForAtoms is removed in Part 6
• GlobalObject::OffThreadPlaceholderObject is removed in bug 1587847
• GlobalObject::resolveOffThreadConstructor is removed in bug 1587847

Depends on D131362

Comment 3

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 2: Remove JSRuntime::numActiveHelperThreadZones. r?jonco!

• AtomsTable::AutoLock is removed in Part 3
  • AutoLockAllAtoms is removed in Part 3
  • GCRuntime::fullGCForAtomsRequested_ is removed in Part 6
  • Zone::canCollect is removed in Part 7

Depends on D131363

Comment 4

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 3: Remove atom lock. r?jonco!

• AutoAccessAtomsZone is removed in Part 9

Depends on D131364

Comment 5

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 4: Remove JSRuntime::offThreadParsesRunning_. r?jonco!

Depends on D131365

Comment 6

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 5: Remove JSRuntime::offThreadParsingBlocked_. r?jonco!

Depends on D131366

Comment 7

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 6: Remove GCRuntime::triggerFullGCForAtoms. r?jonco!

Depends on D131367

Comment 8

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 7: Remove Zone::canCollect. r?jonco!

Depends on D131368

Comment 9

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 8: Remove ZoneGCStats::collectableZoneCount. r?jonco!

Depends on D131369

Comment 10

[Tooru Fujisawa [:arai]]

Attachment: Bug 538450 - Part 9: Remove AutoAccessAtomsZone. r?jonco!

Depends on D131370

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/cec294c924b8
Part 1: Remove Zone::{helperThreadUse_,helperThreadOwnerContext_}. r=jonco
https://hg.mozilla.org/integration/autoland/rev/b1a0f88e06f8
Part 2: Remove JSRuntime::numActiveHelperThreadZones. r=jonco
https://hg.mozilla.org/integration/autoland/rev/c4eee84a4ec4
Part 3: Remove atom lock. r=jonco
https://hg.mozilla.org/integration/autoland/rev/1e8458783db9
Part 4: Remove JSRuntime::offThreadParsesRunning_. r=jonco
https://hg.mozilla.org/integration/autoland/rev/9d22dbb6fc6c
Part 5: Remove JSRuntime::offThreadParsingBlocked_. r=jonco
https://hg.mozilla.org/integration/autoland/rev/c7c122e97b0e
Part 6: Remove GCRuntime::triggerFullGCForAtoms. r=jonco
https://hg.mozilla.org/integration/autoland/rev/33e7c7c5d412
Part 7: Remove Zone::canCollect. r=jonco
https://hg.mozilla.org/integration/autoland/rev/9d74ee42084a
Part 8: Remove ZoneGCStats::collectableZoneCount. r=jonco
https://hg.mozilla.org/integration/autoland/rev/d48623c86ece
Part 9: Remove AutoAccessAtomsZone. r=jonco

Comment 12

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/mozilla-central/rev/cec294c924b8
https://hg.mozilla.org/mozilla-central/rev/b1a0f88e06f8
https://hg.mozilla.org/mozilla-central/rev/c4eee84a4ec4
https://hg.mozilla.org/mozilla-central/rev/1e8458783db9
https://hg.mozilla.org/mozilla-central/rev/9d22dbb6fc6c
https://hg.mozilla.org/mozilla-central/rev/c7c122e97b0e
https://hg.mozilla.org/mozilla-central/rev/33e7c7c5d412
https://hg.mozilla.org/mozilla-central/rev/9d74ee42084a
https://hg.mozilla.org/mozilla-central/rev/d48623c86ece