With the latest version of the postponed job patchset merged, we don't
actually need to go through the contortions of keeping the data in a
global variable; we can just update `data` with multiple calls to
rb_postponed_job_preregister.
Our current implementation of rb_postponed_job_register suffers from
some safety issues that can lead to interpreter crashes (see bug #1991).
Essentially, the issue is that jobs can be called with the wrong
arguments.
We made two attempts to fix this whilst keeping the promised semantics,
but:
* The first one involved masking/unmasking when flushing jobs, which
was believed to be too expensive
* The second one involved a lock-free, multi-producer, single-consumer
ringbuffer, which was too complex
The critical insight behind this third solution is that essentially the
only user of these APIs are a) internal, or b) profiling gems.
For a), none of the usages actually require variable data; they will
work just fine with the preregistration interface.
For b), generally profiling gems only call a single callback with a
single piece of data (which is actually usually just zero) for the life
of the program. The ringbuffer is complex because it needs to support
multi-word inserts of job & data (which can't be atomic); but nobody
actually even needs that functionality, really.
So, this comit:
* Introduces a pre-registration API for jobs, with a GVL-requiring
rb_postponed_job_prereigster, which returns a handle which can be
used with an async-signal-safe rb_postponed_job_trigger.
* Deprecates rb_postponed_job_register (and re-implements it on top of
the preregister function for compatability)
* Moves all the internal usages of postponed job register
pre-registration
Since 0c2d81dada, not all trace events are cleared during VM teardown.
This causes a crash when there is a tracepoint for
`RUBY_INTERNAL_EVENT_GC_EXIT` active during teardown.
The commit looks like a refactoring commit so I think this change was
unintentional.
[Bug #16682]
After 5e86b005c0, I now think ANYARGS is
dangerous and should be extinct. This commit deletes ANYARGS from
rb_ensure, which also revealed many arity / type mismatches.
* ext/objspace/gc_hook.c: remove this file
* ext/-test-/tracepoint/gc_hook.c: new filename for above
* ext/objspace/objspace.c: remove ObjectSpace.after_gc_start_hook=
* test/objspace/test_objspace.rb: remove test
* test/-ext-/tracepoint/test_tracepoint.rb: add above test for
tracepoint re-entry
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44007 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
