Instead of changing the attributes (e.g., Xd bit) of the top-level page-tables,
set them to allow everything. Only leafs of the paging hierarchy are set
according to the paging attributes given by core. Otherwise, top-level page-
table attributes are changed during lifetime, which requires a TLB flush
operation (not intended in the semantic of the kernel/core).
This led to problems when using the non-executable features introduced by
issue #1723 in the recent past.
Recent work related to issue 1723 showed that there is potential
to get rid of code duplication in MMU fault handling especially
with regard to ARM cpus.
* Instead of always re-load page-tables when a thread context is switched
only do this when another user PD's thread is the next target,
core-threads are always executed within the last PD's page-table set
* remove the concept of the mode transition
* instead map the exception vector once in bootstrap code into kernel's
memory segment
* when a new page directory is constructed for a user PD, copy over the
top-level kernel segment entries on RISCV and X86, on ARM we use a designated
page directory register for the kernel segment
* transfer the current CPU id from bootstrap to core/kernel in a register
to ease first stack address calculation
* align cpu context member of threads and vms, because of x86 constraints
regarding the stack-pointer loading
* introduce Align_at template for members with alignment constraints
* let the x86 hardware do part of the context saving in ISS, by passing
the thread context into the TSS before leaving to user-land
* use one exception vector for all ARM platforms including Arm_v6
Fix#2091
* introduce new syscall (core-only) to create privileged threads
* take the privilege level of the thread into account
when doing a context switch
* map kernel segment as accessable for privileged code only
Ref #2091
Always switch to the "exception stack" instead of having a hardware initiated
stack switch during exceptions/interrupts when the privilege level changes only.
Moreover, this commit increases the exception stack slightly.
Ref #2091
* introduces central memory map for core/kernel
* on 32-bit platforms the kernel/core starts at 0x80000000
* on 64-bit platforms the kernel/core starts at 0xffffffc000000000
* mark kernel/core mappings as global ones (tagged TLB)
* move the exception vector to begin of core's binary,
thereby bootstrap knows from where to map it appropriately
* do not map boot modules into core anymore
* constrain core's virtual heap memory area
* differentiate in between user's and core's main thread's UTCB,
which now resides inside the kernel segment
Ref #2091
In the past, a signal context, that was chosen for handling by
'Signal_receiver::pending_signal and always triggered again before
the next call of 'pending_signal', caused all other contexts behind
in the list to starve. This was the case because 'pending_signal'
always took the first pending context in its context list.
We avoid this problem now by handling pending signals in a round-robin
fashion instead.
Ref #2532
Some x86 machines do have a LAPIC speed < 1000 ticks per millisecond
when configured to use the maximum divider (as it was always the case).
But we need microseconds precision for the timeout framework. Thus,
reduce the divider dynamically until the frequency fullfills our
requirements.
Ref #2400
There are hardware timers whose frequency can't be expressed as
ticks-per-microsecond integer-value because only a ticks-per-millisecond
integer-value is precise enough. We don't want to use expensive
floating-point values here but nonetheless want to translate from ticks
to time with microseconds precision. Thus, we split the input in two and
translate both parts separately. This way, we can raise precision by
shifting the values to their optimal bit position. Afterwards, the results
are shifted back and merged together again.
As this algorithm is not so trivial anymore and used by at least three
timer drivers (base-hw/x86_64, base-hw/cortex_a9, timer/pit), move it to a
generic header to avoid redundancy.
Ref #2400
Due to the simplicity of the algorithm that translated from timer ticks
to time, we lost microseconds precision although the timer allows for it.
Ref #2400
When running core as the kernel inside every component, a separate
stack area for core is needed that is different from the user-land
component's one.
Ref #2091
For most base platforms (except linux and sel4), the initialization of
boot modules is the same. Thus, merge this default implementation in the
new unit base/src/core/platform_rom_modules.cc.
Ref #2490
The kernel timer on RPI is able to measure time microseconds-precise.
Howeer, due to a bug, we dropped precision during the ticks-to-time
translation and return only milliseconds-precise time.
Ref #2400
rm_fault.run triggers write on read-only ROM provided by core, which
fails without this patch:
arm - "raised unhandled data abort"
x86 - (silent/invisible) busy loop because write fault gets never resolved
A bug in the timer-ticks-to-microseconds translation of the kernel timer
caused the user time to periodically get stuck for about 32 milliseconds
and then jump forward to the normal level again.
Ref #2400
The recently implemented capability resource trading scheme unfortunately
broke the automated capability memory upgrade mechanism needed by base-hw
kernel/core. This commit splits the capability memory upgrade mechanism
from the PD session ram_quota upgrade, and moves that functionality
into a separate Pd_session::Native_pd interface.
Ref #2398
On ARM, we do not have a component-local hardware time-source. The ARM
performance counter has no reliable frequency as the ARM idle command
halts the counter. Thus, we do not do local time interpolation on ARM.
Except we're on the HW kernel. In this case we can read out the kernel
time instead.
Ref #2435
By separating the session-interface concerns from the mechanics of the
dataspace creation, the code becomes simpler to follow, and the RAM
session can be more easily merged with the PD session in a subsequent
step.
Issue #2407
This patch allows core's 'Signal_transmitter' implementation to sidestep
the 'Env::Pd' interface and thereby adhere to a stricter layering within
core. The 'Signal_transmitter' now uses - on kernels that depend on it -
a dedicated (and fairly freestanding) RPC proxy mechanism for signal
deliver, instead of channeling signals through the 'Pd_session::submit'
RPC function.
Previously, the Genode::Timer::curr_time always used the
Timer_session::elapsed_ms RPC as back end. Now, Genode::Timer reads
this remote time only in a periodic fashion independently from the calls
to Genode::Timer::curr_time. If now one calls Genode::Timer::curr_time,
the function takes the last read remote time value and adapts it using
the timestamp difference since the remote-time read. The conversion
factor from timestamps to time is estimated on every remote-time read
using the last read remote-time value and the timestamp difference since
the last remote time read.
This commit also re-works the timeout test. The test now has two stages.
In the first stage, it tests fast polling of the
Genode::Timer::curr_time. This stage checks the error between locally
interpolated and timer-driver time as well as wether the locally
interpolated time is monotone and sufficiently homogeneous. In the
second stage several periodic and one-shot timeouts are scheduled at
once. This stage checks if the timeouts trigger sufficiently precise.
This commit adds the new Kernel::time syscall to base-hw. The syscall is
solely used by the Genode::Timer on base-hw as substitute for the
timestamp. This is because on ARM, the timestamp function uses the ARM
performance counter that stops counting when the WFI (wait for
interrupt) instruction is active. This instruction, however is used by
the base-hw idle contexts that get active when no user thread needs to
be scheduled. Thus, the ARM performance counter is not a good choice for
time interpolation and we use the kernel internal time instead.
With this commit, the timeout library becomes a basic library. That means
that it is linked against the LDSO which then provides it to the program it
serves. Furthermore, you can't use the timeout library anymore without the
LDSO because through the kernel-dependent LDSO make-files we can achieve a
kernel-dependent timeout implementation.
This commit introduces a structured Duration type that shall successively
replace the use of Microseconds, Milliseconds, and integer types for duration
values.
Open issues:
* The timeout test fails on Raspberry PI because of precision errors in the
first stage. However, this does not render the framework unusable in general
on the RPI but merely is an issue when speaking of microseconds precision.
* If we run on ARM with another Kernel than HW the timestamp speed may
continuously vary from almost 0 up to CPU speed. The Timer, however,
only uses interpolation if the timestamp speed remained stable (12.5%
tolerance) for at least 3 observation periods. Currently, one period is
100ms, so its 300ms. As long as this is not the case,
Timer_session::elapsed_ms is called instead.
Anyway, it might happen that the CPU load was stable for some time so
interpolation becomes active and now the timestamp speed drops. In the
worst case, we would now have 100ms of slowed down time. The bad thing
about it would be, that this also affects the timeout of the period.
Thus, it might "freeze" the local time for more than 100ms.
On the other hand, if the timestamp speed suddenly raises after some
stable time, interpolated time can get too fast. This would shorten the
period but nonetheless may result in drifting away into the far future.
Now we would have the problem that we can't deliver the real time
anymore until it has caught up because the output of Timer::curr_time
shall be monotone. So, effectively local time might "freeze" again for
more than 100ms.
It would be a solution to not use the Trace::timestamp on ARM w/o HW but
a function whose return value causes the Timer to never use
interpolation because of its stability policy.
Fixes#2400
With this, we get rid of platform specific timer interfaces. The new
Timer class does the same as the old Clock class and has a generic
interface. The old Timer class was merely used by the old Clock class.
Also, we get rid of having only one timer instance which we tell with
each method call for which CPU it shall be done. Instead now each Cpu
object has its own Timer member that knows the CPU it works for.
Also, rename all "tics" to "ticks".
Fixes#2347
Previously we did write the SPSR via an MSR instruction without
additional flags. Unfortunately, this tells the CPU to write the
register only partially. This often isn't a problem as the users PSR
reset value normally is conform to our expectations but in some cases
(e.g. PSR endianess bit on WandBoard core #4) the reset value is bad.
Thus, we have to add the CXSF flags (access Control + eXtension + Status
+ Flags) so the CPU overwrites the entire register.
Fixes#2254
This patch reduces the number of exception types by facilitating
globally defined exceptions for common usage patterns shared by most
services. In particular, RPC functions that demand a session-resource
upgrade not longer reflect this condition via a session-specific
exception but via the 'Out_of_ram' or 'Out_of_caps' types.
Furthermore, the 'Parent::Service_denied', 'Parent::Unavailable',
'Root::Invalid_args', 'Root::Unavailable', 'Service::Invalid_args',
'Service::Unavailable', and 'Local_service::Factory::Denied' types have
been replaced by the single 'Service_denied' exception type defined in
'session/session.h'.
This consolidation eases the error handling (there are fewer exceptions
to handle), alleviates the need to convert exceptions along the
session-creation call chain, and avoids possible aliasing problems
(catching the wrong type with the same name but living in a different
scope).
This patch mirrors the accounting and trading scheme that Genode employs
for physical memory to the accounting of capability allocations.
Capability quotas must now be explicitly assigned to subsystems by
specifying a 'caps=<amount>' attribute to init's start nodes.
Analogously to RAM quotas, cap quotas can be traded between clients and
servers as part of the session protocol. The capability budget of each
component is maintained by the component's corresponding PD session at
core.
At the current stage, the accounting is applied to RPC capabilities,
signal-context capabilities, and dataspace capabilities. Capabilities
that are dynamically allocated via core's CPU and TRACE service are not
yet covered. Also, the capabilities allocated by resource multiplexers
outside of core (like nitpicker) must be accounted by the respective
servers, which is not covered yet.
If a component runs out of capabilities, core's PD service prints a
warning to the log. To observe the consumption of capabilities per
component in detail, the PD service is equipped with a diagnostic
mode, which can be enabled via the 'diag' attribute in the target
node of init's routing rules. E.g., the following route enables the
diagnostic mode for the PD session of the "timer" component:
<default-route>
<service name="PD" unscoped_label="timer">
<parent diag="yes"/>
</service>
...
</default-route>
For subsystems based on a sub-init instance, init can be configured
to report the capability-quota information of its subsystems by
adding the attribute 'child_caps="yes"' to init's '<report>'
config node. Init's own capability quota can be reported by adding
the attribute 'init_caps="yes"'.
Fixes#2398
This patch replaces the 'Parent::Quota_exceeded',
'Service::Quota_exceeded', and 'Root::Quota_exceeded' exceptions
by the single 'Insufficient_ram_quota' exception type.
Furthermore, the 'Parent' interface distinguished now between
'Out_of_ram' (the child's RAM is exhausted) from
'Insufficient_ram_quota' (the child's RAM donation does not suffice to
establish the session).
This eliminates ambiguities and removes the need to convert exception
types along the path of the session creation.
Issue #2398
This patch upgrades the cap-space slab only if the kernel runs out of
entries, instead of consuming as much PD-session quota as possible.
Until now, the behavior worked well because the cap-space slab was the
only consumer of PD-session quota. However, once we start accounting all
PD session meta data - and eventually merging the PD and RAM services -
the aggressive scheme stands in the way.
Issue #2398
This commit moves the headers residing in `repos/base/include/spec/*/drivers`
to `repos/base/include/drivers/defs` or repos/base/include/drivers/uart`
respectively. The first one contains definitions about board-specific MMIO
iand RAM addresses, or IRQ lines. While the latter contains device driver
code for UART devices. Those definitions are used by driver implementations
in `repos/base-hw`, `repos/os`, and `repos/dde-linux`, which now need to
include them more explicitely.
This work is a step in the direction of reducing 'SPEC' identifiers overall.
Ref #2403
In order to deliver base-hw as a binary archive, we need to install the
bootstap.o file to bin/. Since bin/ is a global name space shared by all
kernels, this patch renames the object file to bootstap-hw.o and thereby
clarifies the association of the file with base-hw.
By installing the core object to bin/, we follow the same convention as
for regular binaries. This, in turn, enables us to ship core in a
regular binary archive. The patch also adjusts the run tool to pick up
the core object from bin/ for the final linking stage.
The size of the whole table and table entries were exchanged for PML4,
leading to out-of-bound accesses for addesses >= 2^39. Some constants
were lacking type suffixes causing integer overflows.
Added assertions to catch out-of-bound accesses early on.
Fixes#2210Fixes#2211
If we do the tics-to-us translation with one division and multiplication
over the whole argument, like before, we loose microseconds granularity
although the timer frequency allows for such granularity. Thus, we treat
the most significant half and the least significant half of the tics
value separate. Each half is shifted to the best bit position for the
translation, then translated, and then shifted back.
Ref #2347
Previously we pre-calculated the translation errors for the session
quota to make a discret check in the test. But since the order, in which
init childs get their CPU quota isn't always the same anymore (we should
have never made assumptions about that) the translation errors differ
from trial to trial. However, the errors are below 0.01% of the super
period. We now tolerate them in the run script.
Ref #2304
* Acknowledge receive of page-fault signal with ack_signal,
but restart thread execution separately
* use kill_signal_context when disolving a pager_object to prevent race
* Remove bureaucracy in form of Thread_event and Signal_ack_handler
* remove dead code in riscv, namely Thread_base definition
* translation_table_insertions function for ARM drops out,
which was overcautious
There was a race when the component entrypoint wanted to do
'wait_and_dispatch_one_signal'. In this function it raises a flag for
the signal proxy thread to notice that the entrypoint also wants to
block for signals. When the flag is set and the signal proxy wakes up
with a new signal, it tried to cancel the blocking of the entrypoint.
However, if the entrypoint had not reached the signal blocking at this
point, the cancel blocking failed without a solution. Now, the new
Kernel::cancel_next_signal_blocking call solves the problem by storing a
request to cancel the next signal blocking of a thread immediately
without blocking itself.
Ref #2284
There existed a race when 'wait_and_dispatch_one_signal' is called form
a RPC context, because the 'signal_proxy' or 'main' will block and the
signal semaphore, when the EP then calls 'wait_and_dispatch_one_signal',
the signal proxy is woken up ands sends an RPC to the EP, leading to a
dead lock if no further signal arrive, because the EP will then remain
blocked in the signal semaphore.
Therefore, for this case, the signal proxy will now perform a semaphore
up operation and does not perform an RPC if the EP is within
'wait_and_dispatch_one_signal'.
Put the initialization of the cpu cores, setup of page-tables, enabling of
MMU and caches into a separate component that is only used to bootstrap
the kernel resp. core.
Ref #2092
This patch enables warnings if one of the deprecate functions that rely
in the implicit use of the global Genode::env() accessor are called.
For the time being, some places within the base framework continue
to rely on the global function while omitting the warning by calling
'env_deprecated' instead of 'env'.
Issue #1987
This aspect was always enabled when creating a build directory for hw,
but is not enabled anymore due to recent build directory unifications.
On the other hand it is needed for jitter entropy anyway.
Ref #2190
This commit mostly removes the globally visible NR_OF_CPUS define
from the global makefile specifiers defined in the base-hw repository.
Whereever necessary it adds platform specific makefiles to the base
repository when they were missing.
Ref #2190
This patch make the ABI mechanism available to shared libraries other
than Genode's dynamic linker. It thereby allows us to introduce
intermediate ABIs at the granularity of shared libraries. This is useful
for slow-moving ABIs such as the libc's interface but it will also
become handy for the package management.
To implement the feature, the build system had to be streamlined a bit.
In particular, archive dependencies and shared-lib dependencies are now
handled separately, and the global list of 'SHARED_LIBS' is no more.
Now, the variable with the same name holds the per-target list of shared
libraries used by the target.
This patch removes the component_entry_point library, which used to
proved a hook for the libc to intercept the call of the
'Component::construct' function. The mechansim has several shortcomings
(see the discussion in the associated issue) and was complex. So we
eventually discarded the approach in favor of the explicit handling of
the startup.
A regular Genode component provides a 'Component::construct' function,
which is determined by the dynamic linker via a symbol lookup.
For the time being, the dynamic linker falls back to looking up a 'main'
function if no 'Component::construct' function could be found.
The libc provides an implementation of 'Component::construct', which
sets up the libc's task handling and finally call the function
'Libc::Component::construct' from the context of the appllication task.
This function is expected to be provided by the libc-using application.
Consequently, Genode components that use the libc have to implement the
'Libc::Component::construct' function.
The new 'posix' library provides an implementation of
'Libc::Component::construct' that calls a main function. Hence, POSIX
programs that merely use the POSIX API merely have to add 'posix' to the
'LIBS' declaration in their 'target.mk' file. Their execution starts at
'main'.
Issue #2199
This patch removes possible ambiguities with respect to the naming of
kernel-dependent binaries and libraries. It also removes the use of
kernel-specific global side effects from the build system. The reach of
kernel-specific peculiarities has thereby become limited to the actual
users of the respective 'syscall-<kernel>' libraries.
Kernel-specific build artifacts are no longer generated at magic places
within the build directory (like okl4's includes, or the L4 build
directories of L4/Fiasco and Fiasco.OC, or the build directories of
various kernels). Instead, such artifacts have been largely moved to the
libcache. E.g., the former '<build-dir>/l4/' build directory for the L4
build system resides at '<build-dir>/var/libcache/syscall-foc/build/'.
This way, the location is unique to the kernel. Note that various tools
are still generated somewhat arbitrarily under '<build-dir>/tool/' as
there is no proper formalism for building host tools yet.
As the result of this work, it has become possible to use a joint Genode
build directory that is usable with all kernels of a given hardware
platform. E.g., on x86_32, one can now seamlessly switch between linux,
nova, sel4, okl4, fiasco, foc, and pistachio without rebuilding any
components except for core, the kernel, the dynamic linker, and the timer
driver. At the current stage, such a build directory must still be
created manually. A change of the 'create_builddir' tool will follow to
make this feature easily available.
This patch also simplifies various 'run/boot_dir' plugins by removing
the option for an externally hosted kernel. This option remained unused
for many years now.
Issue #2190
This patch decouples the kernel-specific implementation of the dynamic
linker from its kernel-agnostic binary interface. The name of the
kernel-specific dynamic linker binary now corresponds to the kernel,
e.g., 'ld-linux.lib.so' or 'ld-nova.lib.so'. Applications are no longer
linked directly against a concrete instance of the dynamic linker but
against a shallow stub called 'ld.lib.so'. This stub contains nothing
but the symbols provided by the dynamic linker. It thereby represents
the Genode ABI.
At system-integration time, the kernel-specific run/boot_dir back ends
integrate the matching the kernel-specific variant of the dynamic linker
as 'ld.lib.so' into the boot image.
The ABI symbol file for the dynamic linker is located at
'base/lib/symbols/ld'. It contains the joint ABI of all supported
architectures. The new utility 'tool/abi_symbols' eases the creation of
such an ABI symbol file for a given shared library. Its result should be
manually inspected and edited as needed.
The patch removes the 'syscall' library from 'base_libs.mk' to avoid
polluting the kernel-agnostic ABI with kernel-specific interfaces.
Issue #2190
Issue #2195
This cleans up the syscalls that are mainly used to control the
scheduling readiness of a thread. The different use cases and
requirements were somehow mixed together in the previous interface. The
new syscall set is:
1) pause_thread and resume_thread
They don't affect the state of the thread (IPC, signalling, etc.) but
merely decide wether the thread is allowed for scheduling or not, the
so-called pause state. The pause state is orthogonal to the thread state
and masks it when it comes to scheduling. In contrast to the stopped
state, which is described in "stop_thread and restart_thread", the
thread state and the UTCB content of a thread may change while in the
paused state. However, the register state of a thread doesn't change
while paused. The "pause" and "resume" syscalls are both core-restricted
and may target any thread. They are used as back end for the CPU session
calls "pause" and "resume". The "pause/resume" feature is made for
applications like the GDB monitor that transparently want to stop and
continue the execution of a thread no matter what state the thread is
in.
2) stop_thread and restart_thread
The stop syscall can only be used on a thread in the non-blocking
("active") thread state. The thread then switches to the "stopped"
thread state in wich it explicitely waits for a restart. The restart
syscall can only be used on a thread in the "stopped" or the "active"
thread state. The thread then switches back to the "active" thread state
and the syscall returns whether the thread was stopped. Both syscalls
are not core-restricted. "Stop" always targets the calling thread while
"restart" may target any thread in the same PD as the caller. Thread
state and UTCB content of a thread don't change while in the stopped
state. The "stop/restart" feature is used when an active thread wants to
wait for an event that is not known to the kernel. Actually the syscalls
are used when waiting for locks and on thread exit.
3) cancel_thread_blocking
Does cleanly cancel a cancelable blocking thread state (IPC, signalling,
stopped). The thread whose blocking was cancelled goes back to the
"active" thread state. It may receive a syscall return value that
reflects the cancellation. This syscall doesn't affect the pause state
of the thread which means that it may still not get scheduled. The
syscall is core-restricted and may target any thread.
4) yield_thread
Does its best that a thread is scheduled as few as possible in the
current scheduling super-period without touching the thread or pause
state. In the next superperiod, however, the thread is scheduled
"normal" again. The syscall is not core-restricted and always targets
the caller.
Fixes#2104
The initial stack is solely used to initialize the Genode environment
along with the application stack located in the stack area. It never
executes application code. Hence, we can make it small. To check that it
is not dimensioned too small, the patch introduces a sanity check right
before switching to the application stack.
This is a redesign of the root and parent interfaces to eliminate
blocking RPC calls.
- New session representation at the parent (base/session_state.h)
- base-internal root proxy mechanism as migration path
- Redesign of base/service.h
- Removes ancient 'Connection::KEEP_OPEN' feature
- Interface change of 'Child', 'Child_policy', 'Slave', 'Slave_policy'
- New 'Slave::Connection'
- Changed child-construction procedure to be compatible with the
non-blocking parent interface and to be easier to use
- The child's initial LOG session, its binary ROM session, and the
linker ROM session have become part of the child's envirenment.
- Session upgrading must now be performed via 'env.upgrade' instead
of performing a sole RPC call the parent. To make RAM upgrades
easier, the 'Connection' provides a new 'upgrade_ram' method.
Issue #2120
Replace 'dump()' debug utilities within Allocator_avl with Output::print
equivalents, and use the new Avl_tree::for_each utility to simplify
the implementation.
Ref #2159
Instead of solving the problem to deliver ROM modules to core while booting
differently for the several kernels (multi-boot, elfweaver, core re-linking),
this commit unifies the approaches. It always builds core as a library, and
after all binaries are built from a run-script, the run-tool will link an
ELF image out of the core-library and all boot modules. Thereby, core can
access its ROM modules directly.
This approach now works for all kernels except Linux.
With this solution, there is no [build_dir]/bin/core binary available anymore.
For debugging purposes you will find a core binary without boot modules, but
with debug symbols under [run_dir].core.
Fix#2095
base generic code:
* Remove unused verbosity code from mmio framework
* Remove escape sequence end heuristic from LOG
* replace Core_console with Core_log (no format specifiers)
* move test/printf to test/log
* remove `printf()` tests from the log test
* check for exact match of the log test output
base-fiasco:
* remove unused Fiasco::print_l4_threadid function
base-nova:
* remove unused hexdump utility from core
base-hw:
* remove unused Kernel::Thread::_print_* debug utilities
* always print resource summary of core during startup
* remove Kernel::Ipc_node::pd_label (not used anymore)
base*:
* Turn `printf`,`PWRN`, etc. calls into their log equivalents
Ref #1987Fix#2119
* Remove 'test' routine from kernel/core
* Move 'cpu_scheduler' and 'double_list' test to user-land
* Remove 'hw_info' target at all (can be recycled in a topic branch)
Besides adapting the components to the use of base/log.h, the patch
cleans up a few base headers, i.e., it removes unused includes from
root/component.h, specifically base/heap.h and
ram_session/ram_session.h. Hence, components that relied on the implicit
inclusion of those headers have to manually include those headers now.
While adjusting the log messages, I repeatedly stumbled over the problem
that printing char * arguments is ambiguous. It is unclear whether to
print the argument as pointer or null-terminated string. To overcome
this problem, the patch introduces a new type 'Cstring' that allows the
caller to express that the argument should be handled as null-terminated
string. As a nice side effect, with this type in place, the optional len
argument of the 'String' class could be removed. Instead of supplying a
pair of (char const *, size_t), the constructor accepts a 'Cstring'.
This, in turn, clears the way let the 'String' constructor use the new
output mechanism to assemble a string from multiple arguments (and
thereby getting rid of snprintf within Genode in the near future).
To enforce the explicit resolution of the char * ambiguity, the 'char *'
overload of the 'print' function is marked as deleted.
Issue #1987
When running the same kernel in a VM as on the host system and the
kernel boot message from the VM appears on the log output, the run tool
assumes that the host machine has rebooted unexpectedly. With this
commit, an unexpected reboot is assumed only if the kernel boot message
appears at the beginning of a line. On base-hw, we enforce a line feed
at the beginning of the boot message as the SPIKE emulator log starts
with the first message of the kernel lacking a line feed.
Fixes#2041
This patch establishes the sole use of generic headers across all
kernels. The common 'native_capability.h' is based on the version of
base-sel4. All traditional L4 kernels and Linux use the same
implementation of the capability-lifetime management. On base-hw, NOVA,
Fiasco.OC, and seL4, custom implementations (based on their original
mechanisms) are used, with the potential to unify them further in the
future.
This change achieves binary compatibility of dynamically linked programs
across all kernels.
Furthermore, the patch introduces a Native_capability::print method,
which allows the easy output of the kernel-specific capability
representation using the base/log.h API.
Issue #1993
This patch alleviates the need for a Native_capability::Dst at the API
level. The former use case of this type as argument to
Deprecated_env::reinit uses the opaque Native_capability::Raw type
instead. The 'Raw' type contains the portion of the capability that is
transferred as-is when delegating the capability (i.e., when installing
the parent capability into a new component, or when installing a new
parent capability into a new forked Noux process). This information can
be retrieved via the new Native_capability::raw method.
Furthermore, this patch moves the functions for retriving the parent
capability to base/internal/parent_cap.h, which is meant to be
implemented in platform-specific ways. It replaces the former set of
startup/internal/_main_parent_cap.h headers.
Issue #1993
Write tick count of next kernel timer to the guest timed events page if
present. This causes the guest VM to be preempted at the requested tick
count and ensures that the guest VM can not monopolize the CPU if no
traps occur.
The base-hw kernel expects a configured switch-event from the guest VM
to base-hw with ID 30 and target vector 32 to be present in the system
policy.
Issue #2016
Switch kernel timer driver to timed event interface. The base-hw kernel
expects a configured self-event with ID 31 and target vector 32 to be
present in the system policy.
ssue #2016
* The Vm thread is always paused and on exception to make sure that guest VM
execution is suspended whenever we handle an interrupt. Also signal the Vm
session to poke waiting threads (e.g. Virtualbox EMT).
* Implement Vm::proceed
Switch to the mode transition assembly code declared at the _vt_vm_entry
label.
Issue #2016
The entry enables interrupts and initiates a handover to the guest VM by
invoking event number one. The sti instruction is placed at the start to
allow exits to Muen before handing off to the VM if window exiting is
requested.
Issue #2016
This patch introduces the Genode::raw function that prints output
directly via a low-level kernel mechanism, if available.
On base-linux, it replaces the former 'raw_write_str' function.
On base-hw, it replaces the former kernel/log.h interface.
Fixes#2012
The sinfo function declared in sinfo_instance.h creates a static sinfo
object instance and returns a pointer to the caller.
- kernel timer and platform support to use sinfo() function to
instantiate sinfo object
- address and size of the base-hw RAM region via the sinfo API
- log_status() function in sinfo API
Instead of introducing a $(BASE_HW_DIR) variable that has to be defined in each
core makefile for the different base-hw targets, this commit replaces the
$(REP_DIR) variable usage in core.inc files with $(BASE_DIR)/../base-hw.
Ref #1955
This patch removes the outdates doc/architecture.txt since the
topics are covered by the book. We keep repos/os/doc/init.txt
because it contains a few details not present in the book (yet).
The patch streamlines the terminology a bit. Furthermore, it
slightly adjusts a few source-code comments to improve the book's
functional specification chapter.
* Adds public timeout syscalls to kernel API
* Kernel::timeout installs a timeout and binds a signal context to it that
shall trigger once the timeout expired
* With Kernel::timeout_max_us, one can get the maximum installable timeout
* Kernel::timeout_age_us returns the time that has passed since the
calling threads last timeout installation
* Removes all device specific back-ends for the base-hw timer driver and
implements a generic back-end taht uses the kernel timeout API
* Adds assertions about the kernel timer frequency that originate from the
requirements of the the kernel timeout API and adjusts all timers
accordingly by using the their internal dividers
* Introduces the Kernel::Clock class. As member of each Kernel::Cpu object
it combines the management of the timer of the CPU with a timeout scheduler.
Not only the timeout API uses the timeout scheduler but also the CPUs job
scheduler for installing scheduling timeouts.
* Introduces the Kernel::time_t type for timer tic values and values inherited
from timer tics (like microseconds).
Fixes#1972
To avoid the need for adapting the names of the core restricted syscalls
each time we add a public syscall (restricted names must always be
greater than public names), let restricted syscall names simply start at
100 (we should never have more than 100 public syscalls).
Ref #1972
Building a kernel test produced an error about a missing config
apparently because of recent changes in the run tool. So, we add
a dummy XML node as config.
Ref #1972
We do not ensure that the Fpu::Context is 16-byte aligned and,
therefore, should not tell the compiler that we did. Otherwise, the GCC
may optimize operations regarding the addresses of members as it did for
if ((addr_t)_fxsave_area & 0xf) ...
With the declared 16-byte alignment the condition will never become
true.
This patch moves the thread operations from the 'Cpu_session'
to the 'Cpu_thread' interface.
A noteworthy semantic change is the meaning of the former
'exception_handler' function, which used to define both, the default
exception handler or a thread-specific signal handler. Now, the
'Cpu_session::exception_sigh' function defines the CPU-session-wide
default handler whereas the 'Cpu_thread::exception_sigh' function
defines the thread-specific one.
To retain the ability to create 'Child' objects without invoking a
capability, the child's initial thread must be created outside the
'Child::Process'. It is now represented by the 'Child::Initial_thread',
which is passed as argument to the 'Child' constructor.
Fixes#1939
Adjust IRTE_COUNT to specify the number of IRTEs and not the index of
the last IRTE entry. This fixes an off-by-one error in the toggle_mask()
function, where the range check for I/O APIC IRQs wrongly ignored IRQ
23.
The custom version merely differs from the generic one with respect to
the session quota. Since we support the dynamic upgrading of sessions,
we don't need to provide the big amount (128KiB) defined by the custom
version.
This patch supplements each existing connection type with an new
constructor that is meant to replace the original one. The new
one takes a reference to the component's environment as argument and
thereby does not rely on the presence of the globally accessible
'env()' interface.
The original constructors are marked as deprecated. Once we have
completely abolished the use of the global 'env()', we will remove them.
Fixes#1960
All core.inc files now use $BASE_HW_DIR instead of $REP_DIR. The former
is defined by the core.mk file. This allows including core.inc files
from other repositories (e.g. genode-world) for additional platform
support.
Fixes#1955
The old implementation cleared all other bits in the SCU control
register when enabling the SCU, which broke the kernel startup on zynq-
based boards.
By only raising the enable bit, we can keep the initial/default state
e.g. as set up by uboot.
Fixes#1953
This patch cleans up the thread API and comes with the following
noteworthy changes:
- Introduced Cpu_session::Weight type that replaces a formerly used
plain integer value to prevent the accidental mix-up of
arguments.
- The enum definition of Cpu_session::DEFAULT_WEIGHT moved to
Cpu_session::Weight::DEFAULT_WEIGHT
- New Thread constructor that takes a 'Env &' as first argument.
The original constructors are now marked as deprecated. For the
common use case where the default 'Weight' and 'Affinity' are
used, a shortcut is provided. In the long term, those two
constructors should be the only ones to remain.
- The former 'Thread<>' class template has been renamed to
'Thread_deprecated'.
- The former 'Thread_base' class is now called 'Thread'.
- The new 'name()' accessor returns the thread's name as 'Name'
object as centrally defined via 'Cpu_session::Name'. It is meant to
replace the old-fashioned 'name' method that takes a buffer and size
as arguments.
- Adaptation of the thread test to the new API
Issue #1954
This patch moves the base library from src/base to src/lib/base,
flattens the library-internal directory structure, and moves the common
parts of the library-description files to base/lib/mk/base.inc and
base/lib/mk/base-common.inc.
Furthermore, the patch fixes a few cosmetic issues (whitespace and
comments only) that I encountered while browsing the result.
Fixes#1952
This patch makes the former 'Process' class private to the 'Child'
class and changes the constructor of the 'Child' in a way that
principally enables the implementation of single-threaded runtime
environments that virtualize the CPU, PD, and RAM services. The
new interfaces has become free from side effects. I.e., instead
of implicitly using Genode::env()->rm_session(), it takes the reference
to the local region map as argument. Also, the handling of the dynamic
linker via global variables is gone. Now, the linker binary must be
provided as constructor argument.
Fixes#1949
This patch replaces the former 'Pd_session::bind_thread' function by a
PD-capability argument of the 'Cpu_session::create_thread' function, and
removes the ancient thread-start protocol via 'Rm_session::add_client' and
'Cpu_session::set_pager'. Threads are now bound to PDs at their creation
time and implicitly paged according to the address space of the PD.
Note the API change:
This patch changes the signature of the 'Child' and 'Process' constructors.
There is a new 'address_space' argument, which represents the region map
representing the child's address space. It is supplied separately to the
PD session capability (which principally can be invoked to obtain the
PD's address space) to allow the population of the address space
without relying on an 'Pd_session::address_space' RPC call.
Furthermore, a new (optional) env_pd argument allows the explicit
overriding of the PD capability handed out to the child as part of its
environment. It can be used to intercept the interaction of the child
with its PD session at core. This is used by Noux.
Issue #1938
This patch integrates three region maps into each PD session to
reduce the session overhead and to simplify the PD creation procedure.
Please refer to the issue cited below for an elaborative discussion.
Note the API change:
With this patch, the semantics of core's RM service have changed. Now,
the service is merely a tool for creating and destroying managed
dataspaces, which are rarely needed. Regular components no longer need a
RM session. For this reason, the corresponding argument for the
'Process' and 'Child' constructors has been removed.
The former interface of the 'Rm_session' is not named 'Region_map'. As a
minor refinement, the 'Fault_type' enum values are now part of the
'Region_map::State' struct.
Issue #1938
The return code of assign_parent remained unused. So this patch
removes it.
The bind_thread function fails only due to platform-specific limitations
such as the exhaustion of ID name spaces, which cannot be sensibly
handled by the PD-session client. If occurred, such conditions used to
be reflected by integer return codes that were used for diagnostic
messages only. The patch removes the return codes and leaves the
diagnostic output to core.
Fixes#1842
When bringing up the kernel on multiple cores, there is a time span
where some cores already have caches enabled and some don't. Core-local
storage that may be used during this time must be aligned at least to
the maximum line size among global caches. Otherwise, a cached core may
unintentionally prefetch data of a yet uncached core into a global
cache. This may corrupt the view of the uncached core as soon as it
enables caches. However, to determine the exact alignment for every
single ARM platform isn't sensible. Instead, we can align to the minimum
page size assuming that a cache never wants to prefetch from multiple
pages at once and thus fulfills "line size <= page size".
Fixes#1937
This is a generalisation approach of the hw_zynq target. As the boards
typically use UART1 instead of UART0 (used by qemu), we have to
distinguish between those. Moreover, in general hw_zynq does not imply
zynq_qemu anymore, so that the support of particular boards can be
placed in third-party or community repositories (e.g. Genode world).
Fixes#1926
Besides unifying the Msgbuf_base classes across all platforms, this
patch merges the Ipc_marshaller functionality into Msgbuf_base, which
leads to several further simplifications. For example, this patch
eventually moves the Native_connection_state and removes all state
from the former Ipc_server to the actual server loop, which not only
makes the flow of control and information much more obvious, but is
also more flexible. I.e., on NOVA, we don't even have the notion of
reply-and-wait. Now, we are no longer forced to pretend otherwise.
Issue #1832
This patch unifies the CPU session interface across all platforms. The
former differences are moved to respective "native-CPU" interfaces.
NOVA is not covered by the patch and still relies on a custom version of
the core-internal 'cpu_session_component.h'. However, this will soon be
removed once the ongoing rework of pause/single-step on NOVA is
completed.
Fixes#1922
This commit introduces the new `Component` interface in the form of the
headers base/component.h and base/entrypoint.h. The os/server.h API
has become merely a compatibilty wrapper and will eventually be removed.
The same holds true for os/signal_rpc_dispatcher.h. The mechanism has
moved to base/signal.h and is now called 'Signal_handler'.
Since the patch shuffles headers around, please do a 'make clean' in the
build directory.
Issue #1832
This commit replaces the stateful 'Ipc_client' type with the plain
function 'ipc_call' that takes all the needed state as arguments.
The stateful 'Ipc_server' class is retained but it moved from the public
API to the internal ipc_server.h header. The kernel-specific
implementations were cleaned up and simplified. E.g., the 'wait'
function does no longer exist. The badge and exception code are no
longer carried in the message buffers but are handled in kernel-specific
ways.
Issue #610
Issue #1832
This patch moves details about the stack allocation and organization
the base-internal headers. Thereby, I replaced the notion of "thread
contexts" by "stacks" as this term is much more intuitive. The fact that
we place thread-specific information at the bottom of the stack is not
worth introducing new terminology.
Issue #1832
By moving the stub implementation to rm_session_client.cc, we can use
the generic base/include/rm_session/client.h for base-linux and
base-nova and merely use platform-specific implementations.
Issue #1832
This patch establishes a common organization of header files
internal to the base framework. The internal headers are located at
'<repository>/src/include/base/internal/'. This structure has been
choosen to make the nature of those headers immediately clear when
included:
#include <base/internal/lock_helper.h>
Issue #1832
This patch integrates the functionality of the former CAP session into
the PD session and unifies the approch of supplementing the generic PD
session with kernel-specific functionality. The latter is achieved by
the new 'Native_pd' interface. The kernel-specific interface can be
obtained via the Pd_session::native_pd accessor function. The
kernel-specific interfaces are named Nova_native_pd, Foc_native_pd, and
Linux_native_pd.
The latter change allowed for to deduplication of the
pd_session_component code among the various base platforms.
To retain API compatibility, we keep the 'Cap_session' and
'Cap_connection' around. But those classes have become mere wrappers
around the PD session interface.
Issue #1841
This patch removes the SIGNAL service from core and moves its
functionality to the PD session. Furthermore, it unifies the PD service
implementation and terminology across the various base platforms.
Issue #1841
The gnat and gprbuild tools are not necessarily in the PATH when
preparing the port since the effective location is specified by the
--image-muen-gnat-path RUN_OPT.
Use the new Sinfo::get_dev_info function to retrieve device information
in the platform-specific get_msi_params function. If the requested
device supports MSI, set the IRQ and MSI address/data register values to
enable MSIs in remappable format (see VT-d specification, section
5.1.2.2).
Currently only one MSI per device is supported as the subhandle in the
data register is always set to 0.
The new Sinfo::get_dev_info function can be used to retrieve information
for a PCI device with given source-id (SID). The function returns false
if no device information for the specified device exists.
The platform-specific get_msi_params function returns MSI parameters for
a device identified by PCI config space address. The function returns
false if either the platform or the device does not support MSI mode of
operation.
Extend the base-hw Irq_session_component class with _is_msi, _address
and _value variables required to support MSI mode of operation.
Return MSI configuration in info() function if _is_msi is set to true.
This commit adds rocket core on the Zynq FPGA support to base HW. It also takes
advantage of the new timer infrastructure introduced with the privileged 1.8 and
adds improved TLB flush support.
fixes#1880
Do not build core-muen_on library without the muen soecifier set.
Do not reference files of the muen contrib directory in the first
pass of make's rule analysis, when parding the muen specific kernel
makefile.
Fix#1859
The new implementation of the FPU and FPU context is taken out to
separate architecture-dependent header files. The generic Cpu_lazy_state
is deleted. There is no hint about the existence of something like an
FPU in the generic non-architexture-dependent code anymore. Instead the
architecture-dependent CPU context of a thread is extended by an FPU
context where supported.
Moreover, the current FPU implementations are enhanced so that threads
that get deleted now release the FPU when still obtaining it.
Fix#1855
This commit enables multi-processing for all Cortex A9 SoCs we currently
support. Moreover, it thereby enables the L2 cache for i.MX6 that was not
enabled until now. However, the QEMU variants hw_pbxa9 and hw_zynq still
only use 1 core, because the busy cpu synchronization used when initializing
multiple Cortex A9 cores leads to horrible boot times on QEMU.
During this work the CPU initialization in general was reworked. From now
on lots of hardware specifics were put into the 'spec' specific files, some
generic hook functions and abstractions thereby were eliminated. This
results to more lean implementations for instance on non-SMP platforms,
or in the x86 case where cache maintainance is a non-issue.
Due to the fact that memory/cache coherency and SMP are closely coupled
on ARM Cortex A9 this commit combines so different aspects.
Fix#1312Fix#1807
On ARM Cortex A9 platforms the external PL310 L2 cache controller
needs to be initialized dependent on the SoC. For instance on Pandaboard
it needs to call the firmware running in TrustZone's secure world,
on i.MX6 it initializes it directly, on other boards it doesn't need
to be initialized at all, because the bootloader already did so.
Therefore, we should implement the PL310 intialization in board specific
code and not in the base class implementation.
Ref #1312
This commit separates certain SMP aspects into 'spec/smp' subdirectories.
Thereby it simplifies non-SMP implementations again, where no locking
and several platform specific maintainance operations are not needed.
Moreover, it moves several platform specifics to appropriated places,
removes dead code from x86, and starts to turn global static pointers
into references that are handed over.
The main thread's UTCB, used during bootstrap of the main thread before
it allocates its context area, needs to be outside the virtual memory
area controlled by the RM session, because it is needed before the main
thread can access its RM session.
Fix#1804
The test threads previously used a stack size independent from the machine
word width. Qemu was previously configured to provide 64Mb of RAM which isn't
sufficient for x86_64.
Ref #1805
Upgrading the quota of a PD session on HW always triggers a "Quota
exceeded" warning. To prevent unecessary debugging effort in the future,
we explain in an in-code comment that the warning is normal.
Ref #1805
When capabilities are delegated to components, they are added to the UTCB of the
target thread. Before the thread is able to take out the capability id out of
the UTCB and adapt the user-level capability reference counter, it might happen
that another thread of the same component deletes the same capability because
its user-level reference counter reached zero. If the kernel then destroys the
capability, before the same capability id is taken out of all UTCBs, an
inconsitent view in the component is the result. To keep an consistent view in
the multi-threading scenario, the kernel now counts how often it puts a
capability into a UTCB. The threads on the other hand hint the kernel when they
took capabilities out of the UTCB, so the kernel can decrement the counter
again. Only when the counter is zero, capabilities can get destructed.
Fix#1623
Likewise on the x86 branch, we have to remove all virtual memory ranges from the
virtual memory allocator that are used by one-by-one mappings of I/O regions
used by the kernel.
Fix#1797
On the USB Armory, we want to secure different devices than on other i.MX53
implementations. Thus, add a board specific configuration that is interpreted
by the kernel Trustzone initialization.
Ref #1497
Enhance the VM state, that can be accessed by a VMM, by a member
'unsigned irq_injection'. In Kernel::Vm::proceed check, whether
irq_injection is set. If so, check whether irq_injection is a
non-secure IRQ. If so, let the PIC raise this IRQ in the VM and reset
irq_injection.
Ref #1497
'block_for_signal' and 'pending_signal' now set pending flag in signal context
in order to determine pending signal. The context list is also used by the
'Signal_receiver' during destruction.
Fixes#1738
Currently, when a signal arrives in the main thread, the signal dispatcher is
retrieved and called from the main thread, the dispatcher uses a proxy object
that in turn sends an RPC to the entry point. This becomes a problem when the
entry point destroys the dispatcher object, before the dispatch function has
been called by the main thread. Therefore, the main thread should simply send an
RPC to the entry point upon signal arrival and the dispatching should be handled
solely by the entry point.
Issue #1738
Destroying an object within the scope of a lambda/functor executed
in the object pool's apply function leads potentially to memory corruption.
Within the scope the corresponding object is locked and unlocked when
leaving the scope. Therefore, it is illegal to free the object's memory meanwhile.
This commit eliminates several places in core that destroyed wrongly in
the object pool's scope.
Fix#1713
* Move the Synced_interface from os -> base
* Align the naming of "synchronized" helpers to "Synced_*"
* Move Synced_range_allocator to core's private headers
* Remove the raw() and lock() members from Synced_allocator and
Synced_range_allocator, and re-use the Synced_interface for them
* Make core's Mapped_mem_allocator a friend class of Synced_range_allocator
to enable the needed "unsafe" access of its physical and virtual allocators
Fix#1697
Instead of holding SPEC-variable dependent files and directories inline
within the repository structure, move them into 'spec' subdirectories
at the corresponding levels, e.g.:
repos/base/include/spec
repos/base/mk/spec
repos/base/lib/mk/spec
repos/base/src/core/spec
...
Moreover, this commit removes the 'platform' directories. That term was
used in an overloaded sense. All SPEC-relative 'platform' directories are
now named 'spec'. Other files, like for instance those related to the
kernel/architecture specific startup library, where moved from 'platform'
directories to explicit, more meaningful places like e.g.: 'src/lib/startup'.
Fix#1673
Instead of returning pointers to locked objects via a lookup function,
the new object pool implementation restricts object access to
functors resp. lambda expressions that are applied to the objects
within the pool itself.
Fix#884Fix#1658
Propagating the user context-pointer from C++ code to the mode
transition assembly doesn't touch any CPU global data. Thus, we can
reduce the in-sync window.
Fixes#1223
Other platforms implement Kernel::Cpu_context stuff in
kernel/cpu_context.cc. On x86_64, it was implemented in
kernel/thread.cc. The commit fixes this inconsistency to the other
platforms.
Ref #1652
The distinction between Kernel::Thread and Kernel::Thread_base is
unnecessary as currently all Hw platforms would have the same content in
the latter class. Thus I've merged Kernel::Thread_base into
Kernel::Thread. Thereby, Kernel::Thread_event can be moved to
kernel/thread.h.
Ref #1652
The Muen-specific PIC implementation provides the irq_occurred()
function which is used to register an IRQ with the PIC upon thread
exception.
The occurred IRQs are stored in a boolean array internally and handed
out to a CPU via take_request().
The driver uses the timer page containing a vector and timer value to
implement the start_one_shot() and value() functions. The timer value
designates the absolute tick count of the next event.
The address of the time page is acquired using the get_memregion_info
Sinfo API function.
The Muen Sinfo API is used to retrieve information about the execution
environment of a subject running on the Muen Separation Kernel.
While the C++ API is defined in sinfo.h, musinfo.h specifies the
internal format of the information stored in the Sinfo pages provided by
the Muen SK. It is a copy of the file contained in the libmusinfo
library of the Muen project. That is the reason why the coding style in
this file differs from the official style.
Move Platform::setup_irq_mode function from x86 platform_support.cc to
x86_64 specific file. This will enable the upcoming x86_64_muen platform
to provide a separate implementation.
The hw_x86_64_muen platform is a x86/64 base-hw kernel which runs as
isolated subject (guest) on the Muen Separation Kernel (SK) [1].
The platform is implemented as an extension to hw_x86_64 replacing the
PIC and timer drivers with paravirtualized variants. The skeleton
contains a dummy PIC and timer implementation for now.
[1] - http://muen.sk
Add spin loop hint by means of the PAUSE instruction since
wait_for_interrupt is called in a busy loop. This should improve processor
performance and reduce power consumption.
Note: HLT cannot be used since it is a privileged instruction and the idle
thread is executed in userspace.
Move the _core_only_mmio_regions function to the
x86_64/platform_support.cc file. This is required to make it overridable
for other platforms deriving from x86.
For most platforms except of NOVA a distinction between pager entrypoint
and pager activation is not needed, and only exists due to historical
reasons. Moreover, the pager thread's execution path is almost identical
between most platforms excluding NOVA, HW, and Fisco.OC. Therefore,
this commit unifies the pager loop for the other platforms, and removes
the pager activation class.
Moves the Bios Data Area header from base-hw to base. Modifies the
base-nova core console that it uses the header as replacement for
the previous BDA bit logic.
Ref #1625
Three things were done:
* Timouts are measured in an asynchronous way to be able to start counters
after the potentially expensive RPC that starts the timeout.
* Timeouts were increased from 45 and 15 seconds to 60 and 20 seconds
because at least on Arndale, results were not stable enough.
* Counting is done on 'unsigned long long' instead of 'unsigned' because
with the higher timeouts, overflows occured.
Fixes#1628
Since the HW-kern-caps commit, there was a bug in the Platform_thread
constructor. When called for a user thread, the constructor stated 0
as CPU quota at the Kernel_object instead of its quota input-paramater.
Fixes#1620
Instead of using the Genode user-level signal API to signal page-faults to
a page-fault handler, use the kernel API directly. Thereby the accounting
of signal contexts needed for each paging subject can be done easily.
Fix#956
Moreover, be strict when calculating the page-table requirements of
core, which is architecture specific, and declare the virtual memory
requirements of core architecture-wise.
Ref #1588
The ~Irq_session_component relied on the IRQ number obtained by the
corresponding kernel IRQ object to mark the IRQ as free at the IRQ
allocator. However, since the kernel IRQ object is initialized not
before the 'sigh' function is called, the IRQ of sessions that
never called 'sigh' could not be freed correctly. This patch fixes
the problem by not relying on the kernel IRQ object for obtaining
the number in the destructor but using the '_irq_number' member
variable instead.
Instead of organizing page tables within slab blocks and allocating such
blocks dynamically on demand, replace the page table allocator with a
simple, static alternative. The new page table allocator is dimensioned
at compile-time. When a PD runs out of page-tables, we simply flush its
current mappings, and re-use the freed tables. The only exception is
core/kernel that should not produce any page faults. Thereby it has to
be ensured that core has enough page tables to populate it's virtual
memory.
A positive side-effect of this static approach is that the accounting
of memory used for page-tables is now possible again. In the dynamic case
there was no protocol existent that solved the problem of donating memory
to core during a page fault.
Fix#1588
This patch enable clients of core's TRACE service to obtain the
execution times of trace subjects (i.e., threads). The execution time is
delivered as part of the 'Subject_info' structure.
Right now, the feature is available solely on NOVA. On all other base
platforms, the returned execution times are 0.
Issue #813
Add a Platform::setup_irq_mode function which enables the IRQ session to
update the trigger mode and polarity of the associated IRQ according to
the session parameters. On ARM this function is a nop.
This change enables the x86_64 platform to support devices which use
arbitrary trigger modes and polarity settings, e.g. AHCI on QEMU and
real hardware.
Fixes#1528.
Because of helping, it is possible that a core thread that wants to
destroy another thread at the kernel is using the scheduling context of
the thread that shall be destroyed at this point in time. When building
without GENODE_RELEASE defined, this always triggers an assertion in the
kernel. But when building with GENODE_RELEASE defined, this might silently
lead to kernel-memory corruption. This commit eliminates the latter case.
Should be reverted as soon as the scheduler is able to remove its head.
Ref #1537
Placement new can be misleading, as we already overload the new operator
to construct objects via pointers to allocators. To prohibit any problems here,
and to use one consistent approach, we can explicitely construct the object
with the already available 'construct_at' template function.
Ref #1443
* Introduce a hw specific Address_space interface for protection
domains, which combines all memory-virtualization related functionality
* Introduce a core-specific Platform_pd object that solves all the hen-egg
problems formerly distributed in kernel and core-platform code
Ref #595
Ref #1443
The assumption that IRQs in the legacy ISA range are always
edge-triggered is wrong. For the free-for-use IRQs it depends on the
actual device which uses the specific IRQ. Therefore, treat IRQs 9, 10
and 11 as level-triggered.
Enable a platform to specify how the MMIO memory allocator is to be
initialized. On ARM the existing behavior is kept while on x86 the I/O
memory is defined as the entire address space excluding the core only
RAM regions. This aligns the hw_x86_64 I/O memory allocator
initialization with how it is done for other x86 kernels such as NOVA or
Fiasco.
Perform lazy-initialization of FPU state when it is enabled for the
first time. This assures that the FXSAVE area (including the stored
MXCSR) is always properly setup and initialized to the platform default
values.
Perform all FPU-related setup in the Cpu class' init_fpu function instead of
the general system bring-up assembly code.
Set all required control register 0 and 4 flags according to Intel SDM Vol. 3A,
sections 9.2 and 9.6 instead of only enabling FPU error reporting and OSFXSR.
In the past, when the user blocked for an IRQ signal, the last signal was
acknowledged automatically thereby unmasking the IRQ. Now, the signal session
got a dedicated RPC for acknowledging IRQs and the HW back-end of that RPC
acknowledged the IRQ signal too. This led to the situation that IRQs were
unmasked twice. However, drivers expect an interrupt to be unmasked only on
the Irq_session::ack_irq and thus IRQ unmasking was moved from
Kernel::ack_signal to a dedicated kernel call.
Fixes#1493
The thread library (thread.cc) in base-foc shared 95% of the code with
the generic implementation except myself(). Therefore, its
implementation is now separated from the other generic sources into
myself.cc, which allows base-foc to use a foc-specific primitive to
enable our base libraries in L4Linux.
Issue #1491
Physical CPU quota was previously given to a thread on construction only
by directly specifying a percentage of the quota of the according CPU
session. Now, a new thread is given a weighting that can be any value.
The physical counter-value of such a weighting depends on the weightings
of the other threads at the CPU session. Thus, the physical quota of all
threads of a CPU session must be updated when a weighting is added or
removed. This is each time the session creates or destroys a thread.
This commit also adapts the "cpu_quota" test in base-hw accordingly.
Ref #1464
This patch adds const qualifiers to the functions Allocator::consumed,
Allocator::overhead, Allocator::avail, and Range_allocator::valid_addr.
Fixes#1481
Instead of handing over object ids to the kernel, which has to find them
in object pools then, core can simply use object pointers to reference
kernel objects.
Ref #1443
Instead of having an ID allocator per object class use one global allocator for
all. Thereby artificial limitations for the different object types are
superfluent. Moreover, replace the base-hw specific id allocator implementation
with the generic Bit_allocator, which is also memory saving.
Ref #1443
The verb "bin" in the context of destroying kernel objects seems pretty
unusual in contrast to "delete". When reading "bin" in the context of
systems software an association to something like "binary" is more likely.
Ref #1443
* Instead of using local capabilities within core's context area implementation
for stack allocation/attachment, simply do both operations while stack gets
attached, thereby getting rid of the local capabilities in generic code
* In base-hw the UTCB of core's main thread gets mapped directly instead of
constructing a dataspace component out of it and hand over its local
capability
* Remove local capability implementation from all platforms except Linux
Ref #1443
The global capability ID counter is not used by NOVA and Fiasco.OC
and in the future not needed by base-hw too. Thereby, remove the static
counter variable from the generic code base and add it where appropriated.
Ref #1443
Enable platform specific allocations and ram quota accounting for
protection domains. Needed to allocate object identity references
in the base-hw kernel when delegating capabilities via IPC.
Moreover, it can be used to account translation table entries in the
future.
Ref #1443
There are lots of places where a numeric argument of an argument string
gets extraced as signed long value and then assigned to an unsigned long
variable. If the value in the string was negative, it would not be
detected as invalid (and replaced by the default value), but become a
positive bogus value.
With this patch, numeric values which are supposed to be unsigned get
extracted with the 'ulong_value()' function, which returns the default
value for negative numbers.
Fixes#1472
There were two bugs. First, the caller of Kernel::await_signal wasn't
re-activated for scheduling. Second, the caller did not memorize that he
doesn't wait on a receiver anymore which had bad side effects on further
signal handling.
Fix#1459
The port uses the Cortex-A9 private timer for the kernel and an EPIT as
user timer. It was successfully tested on the Wandboard Quad and the CuBox-i
with the signal test. It lacks L2-cache and Trustzone support by now.
Thanks to Praveen Srinivas (IIT Madras, India) and Nikolay Golikov (Ksys Labs
LLC, Russia). This work is partially based on their contributions.
Fix#1467
Do not mask edge-triggered interrupts to avoid losing them while masked,
see Intel 82093AA I/O Advanced Programmable Interrupt Controller
(IOAPIC) specification, section 3.4.2, "Interrupt Mask":
"When this bit is 1, the interrupt signal is masked. Edge-sensitive
interrupts signaled on a masked interrupt pin are ignored (i.e., not
delivered or held pending)"
Or to quote Linus Torvalds on the subject:
"Now, edge-triggered interrupts are a _lot_ harder to mask, because the
Intel APIC is an unbelievable piece of sh*t, and has the edge-detect
logic _before_ the mask logic, so if a edge happens _while_ the device
is masked, you'll never ever see the edge ever again (unmasking will not
cause a new edge, so you simply lost the interrupt)."
So when you "mask" an edge-triggered IRQ, you can't really mask it at
all, because if you did that, you'd lose it forever if the IRQ comes in
while you masked it. Instead, we're supposed to leave it active, and set
a flag, and IF the IRQ comes in, we just remember it, and mask it at
that point instead, and then on unmasking, we have to replay it by
sending a self-IPI." [1]
[1] - http://yarchive.net/comp/linux/edge_triggered_interrupts.html
Ref #1448
In order to match the I/O APIC configuration, a request for user timer
IRQ 0 is remapped to vector 50 (Board::TIMER_VECTOR_USER), all other
requests are transposed by adding the vector offset 48
(Board::VECTOR_REMAP_BASE).
* Enable the use of the FXSAVE and FXRSTOR instructions, see Intel SDM
Vol. 3C, section 2.5.
* The state of the x87 floating point unit (FPU) is loaded and saved on
demand.
* Make the cr0 control register accessible in the Cpu class. This is in
preparation of the upcoming FPU management.
* Access to the FPU is disabled by setting the Task Switch flag in the cr0
register.
* Access to the FPU is enabled by clearing the Task Switch flag in the cr0
register.
* Implement FPU initialization
* Add is_fpu_enabled helper function
* Add pointer to CPU lazy state to CPU class
* Init FPU when finishing kernel initialization
* Add function to retry FPU instruction:
Similar to the ARM mechanism to retry undefined instructions, implement a
function for retrying an FPU instruction. If a floating-point instruction
causes an #NM exception due to the FPU being disabled, it can be retried
after the correct FPU state is restored, saving the current state and
enabling the FPU in the process.
* Disable FPU when switching to different user context:
This enables lazy save/restore of the FPU since trying to execute a
floating point instruction when the FPU is disabled will cause a #NM
exception.
* Declare constant for #NM exception
* Retry FPU instruction on #NM exception
* Assure alignment of FXSAVE area:
The FXSAVE area is 512-byte memory region that must be 16-byte aligned. As
it turns out the alignment attribute is not honored in all cases so add a
workaround to assure the alignment constraint is met by manually rounding
the start of the FXSAVE area to the next 16-byte boundary if necessary.
The LAPIC timer is programmed in one-shot mode with vector 32
(Board::TIMER_VECTOR_KERNEL). The timer frequency is measured using PIT
channel 2 as reference (50ms delay).
Disable PIT timer channel 0 since BIOS programs it to fire periodically.
This avoids potential spurious timer interrupts.
The implementation initializes the Local APIC (LAPIC) of CPU 0 in xapic
mode (mmio register access) and uses the I/O APIC to remap, mask and
unmask hardware IRQs. The remapping offset of IRQs is 48.
Also initialize the legacy PIC and mask all interrupts in order to
disable it.
For more information about LAPIC and I/O APIC see Intel SDM Vol. 3A,
chapter 10 and the Intel 82093AA I/O Advanced Programmable Interrupt
Controller (IOAPIC) specification
Set bit 9 in the RFLAGS register of user CPU context to enable
interrupts on kernel- to usermode switch.
Make the local APIC accessible via its MMIO region by adding a 2 MB
large page mapping at 0xfee00000 with memory type UC.
Note: The mapping is added to the initial page tables to make the APIC
usable prior to the activation of core's page tables, e.g. in the
constructor of the timer class.
The location in memory is arbitrary but we use the same address as the
ARM architecture. Adjust references to virtual addresses in the mode
transition pages to cope with 64-bit values.
The interrupt stack must reside in the mtc region in order to use it for
non-core threads. The size of the stack is set to 56 bytes in order to
hold the interrupt stack frame plus the additional vector number that is
pushed onto the stack by the ISR.
Call the _virt_mtc_addr function with the _mt_isrs label to calculate
the ISR base address in Idt::setup. Again, assume the address to be
below 0x10000.
Use parameter instead of class member variable because it would get
stored into the mtc region otherwise. In a further iteration only the
actual IDT should be saved into the mtc, not the complete class
instance. Currently the class instance size is equal to the IDT table
size.
The class provides the load() function which reloads the GDTR with the
GDT address in the mtc region. This is needed to make the segments
accessible to non-core threads.
Make the _gdt_start label global to use it in the call to
_virt_mtc_addr().
Use the _mt_tss label and the placement new operator to create the
Tss class instance in the mtc region. Update the hard-coded
TSS base address to use the virtual mtc address.
On exception, the CPU first checks the IDT in order to find the
associated ISR. The IDT must therefore be placed in the mode transition
pages to make them available for non-core threads.
