Currently interface lookups are do a binary search over all the interfaces
an object implements. Its possible to do this lookup in constant time using for
instance the gcj algorighm described at:
http://gcc.gnu.org/ml/java/1999-q3/msg00377.html
This is an implementation of that based on GAtomicArray.
We implement lock free interface lookup by moving the n_ifaces
counter into memory pointed to by TypeNode->iface_entries, and
then updating this in RCU-style by always copying it, modifying
the copy and then when the modification is done replace the old
pointer with g_atomic_pointer_set.
There is one additional complexity when freeing the old memory,
since the old memory region can be in use. To handle this we
don't free such memory, but put it on a free list and reuse it
later. This means that lock-free lookups must be able to
handle the memory being modified in random ways without crashing,
and at the end we verify that the memory didn't change and the
transaction is ok.
With this infrastructure the patch then implements a lock-free
version of type_lookup_iface_entry_L called type_lookup_iface_vtable_I
and use it in: g_type_interface_peek, g_type_interface_peek_parent
and type_node_check_conformities_UorL.
Using the performance tests from bug 557100 shows that the general
performance difference is negligible, but the lack of a lock for each
type check and interface vfunc call should greatly enhance threaded
scalability.
This adds supports for a lock-less a non-shrinking growable array.
You can use it to do reads using no locks, as long as your read-code
can handle that during the read transaction the object can be modified
by another writer (but it will not change size or be freed), and you
can only trust the result once the transaction has finished successfully.
This doesn't free things like RCU normally does, instead it pushes the
memory on a free list that is reused for other atomic arrays.
The n_children variable can be written when locked, while the n_supers
variable is read at any time. As they both share the same bytes,
accessing them is not threadsafe.
This patch puts them into different bytes.
Thanks to Xan Lopez and valgrind for noticing this.
Store whether the object has a toggleref before decrementing the
refcount to prevent race condition when two threads simultaneously
try to unref an object with a refcount of 2.
Patch by Antoine Tremblay.
https://bugzilla.gnome.org/show_bug.cgi?id=551706
This avoids a bunch of code and makes construction of simple objects
faster.
Object construction performance improvement:
Non-Threaded Threaded
Simple: 14% 5%
Complex: -1.1% -2.2%
Other tests stable.
https://bugzilla.gnome.org/show_bug.cgi?id=557100
If the class has no properties there could be no notification anyway.
This is an important optimization for construction of simple objects.
Object construction performance improvement:
Non-Threaded Threaded
Simple: 84% 91%
Complex: -1.4% -0.6%
Other tests stable.
https://bugzilla.gnome.org/show_bug.cgi?id=557100
This is both cleaner and faster (it avoids function calls and
zeroing the memory twice).
Object construction performance improvement:
Non-Threaded Threaded
Simple: 11% 1.3%
Complex: 8% 6%
Other tests stable.
https://bugzilla.gnome.org/show_bug.cgi?id=557100
Commit 789e260638 tried to add support for -?, but there is a typo
and instead -h was added when already present instead of -? for one
of the cases.
It works without this corrections, because all unrecognized options
trigger usage showing as well, but this is more correct.
This was bug 556706 originally.
Tools like clang fail to recognize that stanzas like
g_return_if_fail (GTK_IS_FOO (w)) guarantee w != NULL. By minimally
rewriting the type-checking macros, we can avoid these false positives.
Since @filename@ contains the full filename as given to the glib-mkenum
command, possibly including path elements (e.g. when using a non-srcdir
build), it is unsuitable to use in a #include statement in the generated
file if one wants to distribute it. This patch adds @basename@ which
expands to the base name of the input filename. Bug #587307.
Update various README files to refer to git instead of svn.
Add a README.commits that is pretty much a copy of the same file
in GTK+. Also discontinue ChangeLog files.
2009-03-13 Kristian Rietveld <kris@imendio.com>
* gsignal.c (signal_lookup_closure): when defaulting to the only
item in the array, check if this is indeed the default closure.
(patch by Tim Janik).
svn path=/trunk/; revision=7979
GLib users buildable with gcc 4.4. Patch by Jakub Jelinek.
* glib/gatomic.[hc]: Add G_GNUC_MAY_ALIAS to pointer arguments,
fix macro versions to only operate on objects of the same size.
* glib/gdataset.c:
* glib/gthread.[hc]:
* glib/gdatasetprivate.h: Remove unnecessary casts in
g_atomic_pointer_get calls.
svn path=/trunk/; revision=7875
* configure.in: Define an ENABLE_REGEX macro
* gobject/gboxed.c: Don't refer to g_regex_ref if ENABLE_REGEX
is not defined.
svn path=/trunk/; revision=7815
2009-01-02 Behdad Esfahbod <behdad@gnome.org>
Bug 565136 – Gobject's "notify" signal parameters are wrong in gtk-doc
Patch from Andrzej Zaborowski
* gobject.c (g_object_do_class_init): Fix param order in docs.
svn path=/trunk/; revision=7759
* gtypemodule.c (g_type_module_use): Always reset the use count
to its previous value before returning FALSE. Pointed out by
Johan Billien.
svn path=/trunk/; revision=7725
