When repeatedly enqueing and dequeing a single item in a Queue we end
up faulting in all the pages for the underlying Vector. This is a
performance issue - especially where the element type is large.
Previously the Queue class used a SinglyLinkedList to manage its queue
segments. This changes the Queue class to use the IntrusiveList class
instead which saves us one allocation per segment.
We leak a ref() onto every user process when constructing them,
either via Process::create_user_process(), or via Process::sys$fork().
This ref() is balanced by a corresponding unref() in
Thread::WaitBlockCondition::finalize().
Since kernel processes don't have a leaked ref() on them, this led to
an extra Process::unref() on kernel processes during finalization.
This happened during every boot, with the `init_stage2` process.
Found by turning off kfree() scrubbing. :^)
This removes the '$' character so that it is easier to copy commands
directly from the build instructions and then executing them without
first having to remove the '$' character.
Double ampersands (&&) marking in menus is meant to provide a way
to show the ampersand, since using just one would turn it
into a modifier that sets the shortcut for the next character.
Unfortunately, while the first character had a special case to avoid
marking this set, the marking was still calculated
for the second character.
The fix is rather simple: just skip then the following character!
This issue applied only to the visual part of the Menu.
The WindowServer calculation for the shortcut character is working
properly, i.e. ignores escaped ampersands.
If the text-for-rendering of the last selected node is empty, the select
all implementation would end up setting the index to -1. This value is
used directly for a substring length in the copy text implementation,
thus would cause a failed assertion.
In case we are about to delete the PID directory, we clear the Process
pointer. If someone still holds a reference to the PID directory (by
opening it), we still need to delete the process, but we can't delete
the directory, so we will keep it alive, but any operation on it will
fail by propogating the error to userspace about that the Process was
deleted and therefore there's no meaning to trying to do operations on
the directory.
Fixes#8576.
Before this change PNGWriter::add_chunk used to make a copy of
PNGChunk's ByteBuffer to prepend the size of the data.
With this change, 4-byte space is saved from the beginning and written
at the end of the operation. Avoiding this copy yields significant
speed up.
Rather than parsing the selector every time we want to check it, we
now parse it once at the beginning.
A bonus effect of this is that we now support a selector list in
:not(), instead of just a single selector, though only when using
the new parser.
The end goal is to make the PseudoClass::not_selector be a Selector
instead of a String that is repeatedly re-parsed. But since Selector
contains a Vector of ComplexSelectors, which each have a Vector of
SimpleSelectors, it's probably a good idea to not be passing them
around by value anyway. :^)
Same reasoning again! This is the last one.
While I was at it, I added the two remaining CSS2.2 pseudo-elements,
::first-line and ::first-letter. All 4 are handled in the new CSS
parser, including with the compatibility single-colon syntax. I have
not added support to the old parser.
Previously, SimpleSelectors optionally had Attribute-selector data
as well as their main type. Now, they're either one or the other,
which better matches the spec, and makes parsing and matching more
straightforward.