Change JSLock::dropAllLocks() and friends to use lock() and unlock().
<https://webkit.org/b/128451>
Reviewed by Geoffrey Garen.
Currently, JSLock's dropAllLocks(), dropAllLocksUnconditionally(), and
grabAllLocks() implement locking / unlocking by duplicating the code from
lock() and unlock(). Instead, they should just call lock() and unlock().
* runtime/JSLock.cpp:
(JSC::JSLock::lock):
(JSC::JSLock::unlock):
- Modified lock() and unlock() into a version that takes an entry count
to lock / unlock. The previous lock() and unlock() now calls these
new versions with an entry count of 1.
(JSC::JSLock::dropAllLocks):
(JSC::JSLock::dropAllLocksUnconditionally):
(JSC::JSLock::grabAllLocks):
- Delegate to unlock() and lock() instead of duplicating the lock / unlock
code.
- There a some differences with calling lock() instead of duplicating its
code in grabAllLock() i.e. lock() does the following additional work:
1. lock() does a re-entry check that is not needed by grabAllLocks().
However, this is effectively a no-op since we never own the JSLock
before calling grabAllLocks().
2. set VM stackPointerAtVMEntry.
3. update VM stackLimit and reservedZoneSize.
4. set VM lastStackTop.
These 3 steps are just busy work which are also effective no-ops
because immediately after lock() returns, grabAllLocks() will write
over those values with their saved versions in the threadData.
* runtime/JSLock.h:
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@163820 268f45cc-cd09-0410-ab3c-d52691b4dbfc
3 files changed
