This patch makes it so that while the cycle collector is running methods are called
on the concrete implementation nsCycleCollectorLogger, rather than the interface
nsICycleCollectorListener. This makes explicit the requirement that we have to be
very careful about what we call during the cycle collector, and should make it
possible for the GC rooting static analysis to understand what is happening.
The UUID of nsICycleCollectorHandler was changed to appease the UUID commit hook.
Various parts of the first half of BeginCollection() can start an incremental GC.
This is bad because running the GC and CC at the same time can cause the CC to end
up with pointers to dead JS objects.
To avoid this, we finish any incremental GC in progress in BeginCollection. This
is slow, but hopefully it is rare.
They are kept around for the sake of the standalone glue, which is used
for e.g. webapprt, which doesn't have direct access to jemalloc, and thus
still needs a wrapper to go through the xpcom function list and get to
jemalloc from there.
Crashing here is apparently fairly common. This restores the old behavior, so we at least
don't crash immediately, but instead enter a slow downward spiral of leaking.
This improves on the old behavior in that we only try and fail to grow the hash table once,
rather than on every add. khuey I think reported that the browser got very slow, because
you are going through the very slowest path of the allocator over and over.
It is a little cleaner to use this helper method if we only care about the CCJSRuntime pointer,
and it will let us move some of these methods out of this file more easily.
I kept all the existing PL_DHashTableAdd() calls fallible, in order to be
conservative, except for the ones in nsAtomTable.cpp which already were
followed immediately by an abort on failure.
I kept all the existing PL_DHashTableAdd() calls fallible, in order to be
conservative, except for the ones in nsAtomTable.cpp which already were
followed immediately by an abort on failure.
It feels safer to use a function with a new name, rather than just changing the
behaviour of the existing function.
For most of these cases the PL_DHashTableLookup() result was checked with
PL_DHASH_ENTRY_IS_{FREE,BUSY} so the conversion was easy. A few of them
preceded that check with a useless null check, but the intent of these was
still easy to determine.
I'll do the trickier ones in subsequent patches.
Currently the setting of PLDHashTable::ops is very haphazard.
- PLDHashTable has no constructor, so it's not auto-nulled, so lots of places
null it themselves.
- In the fallible PLDHashTable::Init() function, if the entry storage
allocation fails we'll be left with a table that has |ops| set -- indicating
it's been initialized -- but has null entry storage. I'm not certain this can
cause problems but it feels unsafe, and some (but not all) callers of Init()
null it on failure.
- PLDHashTable does not null |ops| in Finish(), so some (but not all) callers
do this themselves.
This patch makes things simpler.
- It adds a constructor that zeroes |ops|.
- It modifies Init() so that it only sets |ops| once success is ensured.
- It zeroes |ops| in Finish().
- Finally, it removes all the now-unnecessary |ops| nulling done by the users
of PLDHashTable.
