Regressed in 8a4cc735b9.
We stopped generating "process created" when enabling profiling,
which led to Profiler getting confused about the missing events.
Fixes off-by-one caused by reading the register directly
without adding a 1 to it, because AHCI reports 1 less port than
the actual number of ports supported.
This implements the macOS API malloc_good_size() which returns the
true allocation size for a given requested allocation size. This
allows us to make use of all the available memory in a malloc chunk.
For example, for a malloc request of 35 bytes our malloc would
internally use a chunk of size 64, however the remaining 29 bytes
would be unused.
Knowing the true allocation size allows us to request more usable
memory that would otherwise be wasted and make that available for
Vector, HashTable and potentially other callers in the future.
Previously calls to perf_event() would end up in a process-specific
perfcore file even though global profiling was enabled. This changes
the behavior for perf_event() so that these events are stored into
the global profile instead.
On my machine, it only sets PRC and not PCC.
Confirmed to happen on:
- 8086:9ca2 (Intel Corporation Wildcat Point-LP SATA Controller
[AHCI Mode] (rev 03))
On my bare metal machine, enabling it as this point causes it to
instantly send an interrupt, and we're too early in the process
to be able to handle AHCI interrupts. The interrupts were being
enabled in the initialize function anyway.
Confirmed to happen on:
- 8086:9ca2 (Intel Corporation Wildcat Point-LP SATA Controller
[AHCI Mode] (rev 03))
- 8086:3b22 (Intel Corporation 5 Series/3400 Series Chipset
6 port SATA AHCI Controller (rev 06))
Occasionally we'll see messages in the serial console like:
handle_tcp: unexpected flags in FinWait1 state
In these cases it would be nice to know what flags we are receiving that
we aren't expecting.
The following KUBSAN crash on startup was reported on discord:
```
UHCI: Started
KUBSAN: reference binding to null pointer of type struct UHCIController
KUBSAN: at ../../Kernel/Devices/USB/UHCIController.cpp, line 67
```
After inspecting the code, it became clear that there's a window of time
where the kernel task which monitors the UHCI port can startup and start
executing before the UHCIController constructor completes. This leaves
the singleton pointing to nullptr, thus in the duration of this race
window the "UHCI port proc" thread will go an and de-reference the null
pointer when trying to read for status changes on the UHCI root ports.
Reported-by: @stelar7
Reported-by: @bcoles
Fixes: #6154
AnonymousVMObject::create_with_physical_page(s) can't be NonnullRefPtr
as it allocates internally. Fixing the API then surfaced an issue in
ScatterGatherList, where the code was attempting to create an
AnonymousVMObject in the constructor which will not be observable
during OOM.
Fix all of these issues and start propagating errors at the callers
of the AnonymousVMObject and ScatterGatherList APis.
This change looks more involved than it actually is. This simply
reshuffles the previous Process constructor and splits out the
parts which can fail (resource allocation) into separate methods
which can be called from a factory method. The factory is then
used everywhere instead of the constructor.
This code was unlocking the lock directly, but the Locker is still
attached, causing the lock to be unlocked an extra time, hence
corrupting the internal lock state.
This is extra confusing though, as complete_current_request() runs
without a lock which also looks like a bug. But that's a task for
another day.
The separate backtrace that the PANIC emits isn't useful and just adds
more data to visually filter from the output when debugging an issue.
Instead of calling PANIC, just emit the message with dbgln() and
manually halt the system.
If we are attempting to emit debugging information about an unhandleable
page fault, don't crash trying to kill threads or dump processes if the
current_thread isn't set in TLS. Attempt to keep proceeding in order to
dump as much useful information as possible.
Related: #6948
We were using ELF::Image::section(0) to indicate the "undefined"
section, when what we really wanted was just Optional<Section>.
So let's use Optional instead. :^)
The function fstatat can do the same thing as the stat and lstat
functions. However, it can be passed the file descriptor of a directory
which will be used when as the starting point for relative paths. This
is contrary to stat and lstat which use the current working directory as
the starting for relative paths.
Previously we didn't retransmit lost TCP packets which would cause
connections to hang if packets were lost. Also we now time out
TCP connections after a number of retransmission attempts.
This wakes up NetworkTask every 500 milliseconds so that it can send
pending delayed TCP ACKs and isn't forced to send all of them early
when it goes to sleep like it did before.
When establishing the connection we should send ACKs right away so
as to not delay the connection process. This didn't previously
matter because we'd flush all delayed ACKs when NetworkTask waits
for incoming packets.
Ideally we would never allocate under a spinlock, as it has many
performance and potentially functionality (deadlock) pitfalls.
We violate that rule in many places today, but we need a tool to track
them all down and fix them. This change introduces a new macro option
named `KMALLOC_VERIFY_NO_SPINLOCK_HELD` which can catch these
situations at runtime via an assert.
Avoid holding the sockets_by_tuple lock while allocating the TCPSocket.
While checking if the list contains the item we can also hold the lock
in shared mode, as we are only reading the hash table.
In addition the call to from_tuple appears to be superfluous, as we
created the socket, so we should be able to just return it directly.
This avoids the recursive lock acquisition, as well as the unnecessary
hash table lookups.
This ensures that the lost_samples field is set to zero for the
first sample. We didn't lose any samples before the first sample
so this is the correct value. Without this Profiler gets confused
and draws the graph for the process which contains the first CPU
sample incorrectly (all zeroes usually).
We can lose profiling timer events for a few reasons, for example
disabled interrupts or system slowness. This accounts for lost
time between CPU samples by adding a field lost_samples to each
profiling event which tracks how many samples were lost immediately
preceding the event.
This updates the profiling subsystem to use a separate timer to
trigger CPU sampling. This timer has a higher resolution (1000Hz)
and is independent from the scheduler. At a later time the
resolution could even be made configurable with an argument for
sys$profiling_enable() - but not today.
Make messages which should be fatal, actually fail the build.
- FATAL is not a valid mode keyword. The full list is available in the
docs: https://cmake.org/cmake/help/v3.19/command/message.html
- SEND_ERROR doesn't immediately stop processing, FATAL_ERROR does.
We should immediately stop if the Toolchain is not present.
- The app icon size validation was just a WARNING that is easy to
overlook. We should promote it to a FATAL_ERROR so that people will
not overlook the issue when adding a new application. We can only make
the small icon message FATAL_ERROR, as there is currently one
violation of the medium app icon validation.
Note that the changes to IPv4Socket::create are unfortunately needed as
the return type of TCPSocket::create and IPv4Socket::create don't match.
- KResultOr<NonnullRefPtr<TcpSocket>>>
vs
- KResultOr<NonnullRefPtr<Socket>>>
To handle this we are forced to manually decompose the KResultOr<T> and
return the value() and error() separately.
The make<T> factory function allocates internally and immediately
dereferences the pointer, and always returns a NonnullOwnPtr<T> making
it impossible to propagate an error on OOM.
The make<T> factory function allocates internally and immediately
dereferences the pointer, and always returns a NonnullOwnPtr<T> making
it impossible to propagate an error on OOM.
Modify the API so it's possible to propagate error on OOM failure.
NonnullOwnPtr<T> is not appropriate for the ThreadTracer::create() API,
so switch to OwnPtr<T>, use adopt_own_if_nonnull() to handle creation.
Currently, when passing buffers into VirtIOQueues, we use scatter-gather
lists, which contain an internal vector of buffers. This vector is
allocated, filled and the destroy whenever we try to provide buffers
into a virtqueue, which would happen a lot in performance cricital code
(the main transport mechanism for certain paravirtualized devices).
This commit moves it over to using VirtIOQueueChains and building the
chain in place in the VirtIOQueue. Also included are a bunch of fixups
for the VirtIO Console device, making it use an internal VM::RingBuffer
instead.
We want to move this out of the AHCI subsystem into the VM system,
since other parts of the kernel may need to perform scatter-gather IO.
We rename the current VM::ScatterGatherList impl that's used in the
virtio subsystem to VM::ScatterGatherRefList, since its distinguishing
feature from the AHCI scatter-gather list is that it doesn't own its
buffers.
