The kernel now supports basic profiling of all the threads in a process
by calling profiling_enable(pid_t). You finish the profiling by calling
profiling_disable(pid_t).
This all works by recording thread stacks when the timer interrupt
fires and the current thread is in a process being profiled.
Note that symbolication is deferred until profiling_disable() to avoid
adding more noise than necessary to the profile.
A simple "/bin/profile" command is included here that can be used to
start/stop profiling like so:
$ profile 10 on
... wait ...
$ profile 10 off
After a profile has been recorded, it can be fetched in /proc/profile
There are various limits (or "bugs") on this mechanism at the moment:
- Only one process can be profiled at a time.
- We allocate 8MB for the samples, if you use more space, things will
not work, and probably break a bit.
- Things will probably fall apart if the profiled process dies during
profiling, or while extracing /proc/profile
Using int was a mistake. This patch changes String, StringImpl,
StringView and StringBuilder to use size_t instead of int for lengths.
Obviously a lot of code needs to change as a result of this.
This patch makes it possible to make memory regions non-readable.
This is enforced using the "present" bit in the page tables.
A process that hits an not-present page fault in a non-readable
region will be crashed.
This is a very simple implementation of the cal command to display
a calendar into the command line.
For now this only prints the current month highlighting the current
day.
Kernel modules can now be unloaded via a syscall. They get a chance to
run some code of course. Before deallocating them, we call their
"module_fini" symbol.
It's now possible to load a .o file into the kernel via a syscall.
The kernel will perform all the necessary ELF relocations, and then
call the "module_init" symbol in the loaded module.
This defaults to 1500 for all adapters, but LoopbackAdapter increases
it to 65536 on construction.
If an IPv4 packet is larger than the MTU, we'll need to break it into
smaller fragments before transmitting it. This part is a FIXME. :^)
Previously it was not possible to see what each thread in a process was
up to, or how much CPU it was consuming. This patch fixes that.
SystemMonitor and "top" now show threads instead of just processes.
"ps" is gonna need some more fixing, but it at least builds for now.
Fixes#66.
LibProtocol::Client::start_download() now gives you a Download object
with convenient hooks (on_finish & on_progress).
Also, the IPC handshake is snuck into the Client constructor, so you
don't need to perform it after instantiating a Client.
This makes using LibProtocol much more pleasant. :^)
The DownloadFinished message from the server now includes a buffer ID
that can be mapped into the client program.
To avoid prematurely destroying the buffer, the server will hang on to
it until the client lets it know that they're all good. That's what the
ProtocolServer::DisownSharedBuffer message is about.
In the future it would be nice if the kernel had a mechanism to allow
passing ownership of a shared buffer along with an IPC message somehow.
This patch adds muting to ASMixer, which works by substituting what we
would normally send to the sound card with zero-filled memory instead.
We do it this way to ensure that the queued sample buffers keep getting
played (silently.)
This is obviously not the perfect way of doing this, and in the future
we should improve on this, and also find a way to utilize any hardware
mixing functions in the sound card.
Add an initial implementation of pthread attributes for:
* detach state (joinable, detached)
* schedule params (just priority)
* guard page size (as skeleton) (requires kernel support maybe?)
* stack size and user-provided stack location (4 or 8 MB only, must be aligned)
Add some tests too, to the thread test program.
Also, LibC: Move pthread declarations to sys/types.h, where they belong.
This can be implemented entirely in userspace by calling tcgetattr().
To avoid screwing up the syscall indexes, this patch also adds a
mechanism for removing a syscall without shifting the index of other
syscalls.
Note that ports will still have to be rebuilt after this change,
as their LibC code will try to make the isatty() syscall on startup.
VM regions can now be marked as stack regions, which is then validated
on syscall, and on page fault.
If a thread is caught with its stack pointer pointing into anything
that's *not* a Region with its stack bit set, we'll crash the whole
process with SIGSTKFLT.
Userspace must now allocate custom stacks by using mmap() with the new
MAP_STACK flag. This mechanism was first introduced in OpenBSD, and now
we have it too, yay! :^)
This patch adds these API's:
- pthread_mutex_init()
- pthread_mutex_lock()
- pthread_mutex_unlock()
No mutex attributes are supported yet, so we only do the simplest mutex
wihout recursive locking.
It's now possible to block until another thread in the same process has
exited. We can also retrieve its exit value, which is whatever value it
passed to pthread_exit(). :^)
By default, disk_benchmark will now use the O_DIRECT flag, causing it
to bypass the kernel's disk caches. This gives you "disk performance"
numbers rather than "disk cache performance" numbers.
You can use "disk_benchmark -c" to enable the caches.
Fixes#703.
The Plan9 OS has this program that can test a system call with the
given arguments. For the most basic system calls it can be very
helpful and aid with testing or just to play with a given syscall
without writing a dedicated program.
Some examples:
syscall write 1 hello 5
syscall -o read 0 buf 5
syscall mkdir /tmp/my-dir
syscall exit 2
...
I wrote a version of nl for Serenity with a lot but not all of the
options in POSIX nl. It includes line count type (-b), increment (-i),
delimiter (-s), start number (-v), and width (-w).
Now gets a true byte count by using the file size.
* When giving a single-line string without a trailing newline, the line
count should not go up ('printf "test" | wc -l' should output '0')
* Doesn't hang up when using two or more switch options in a row.
(It would hang if I did 'wc -lw test.frm').
While mine works with multiple args like that, they don't switch
anything, you have to do wc -l -w etc but I think that is an issue
with CArgsParser.
* It can now take standard input without needing a "-".
* When encountering a file that doesn't exist, it doesn't exit.
It prints the counts for each file that does, and prints an error to
stderr for each file that doesn't.
* Has slight buffering between counts to be closer to GNU and BSD wc.
This is roughly twice as fast as the old 4 KB buffer size. We still
don't go nearly as fast as "cp", since we don't ftruncate() up front
like "cp" does.
Since we usually know how many bytes we're going to write, we can be
nice to the kernel and ftruncate() the destination to the expected size
up front, reducing the amount of FS churn.
aplay used to quit as soon as the last enqueue of new buffer data
was sucessful. Because the connection closes as soon as the
application quits, samples were still in the buffer of the
ASBufferQueue as playback was halted.
Node.normalize() is a standard DOM API that coalesces Text nodes.
To avoid clashing with that, rename it to fixup().
This patch also makes it happen automagically as part of parsing.
Instead of HtmlView clients having to worry about parsing and loading
the default CSS, just take care of it inside StyleResolver.
The default style is automatically inserted into the stylesheet list,
at the very start, so everyone else gets a chance to override it.
This is a simple command that can be used to display HTML from a given
file, or from the standard input, in an HtmlView. It replaces the `tho`
(test HTML output) command.
