This patch augments the existing session/session.h with useful types for
the session creation:
* The new 'Insufficient_ram_quota' and 'Insufficient_cap_quota'
exceptions are meant to supersede the old 'Quota_exceeded' exception
of the 'Parent' and 'Root' interfaces.
* The 'Session::Resources' struct subsumes the information about the
session quota provided by the client.
* The boolean 'Session::Diag' type will allow sessions to operate in a
diagnostic mode.
* The existing 'Session_label' is not also available under the alias
'Session::Label'.
* A few helper functions ease the extraction of typed session arguments
from the session-argument string.
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 accessor is useful to eagerly expand the slab with new slab blocks,
side stepping the slab's built-in policy for the allocation of new slab
blocks.
This is particularly important when using the slab for allocating the
cap space meta-data for the base-hw kernel. To guarantee that the slab
gets never exhausted in the kernel, it is expanded before entering the
kernel.
With the introduction of the 'Out_of_caps' exception type, the slab
needs to consider exceptions during the call of '_new_slab_block' by
reverting the 'nested' state.
The old download location is very shaky resp. currently unavailable and
also other projects (e.g., Gentoo and Linux From Scratch) use this
location. Note, the archive hash does _not_ change.
By building the posix library as shared object with an ABI, we
effectively decouple posix-using programs from the library
implementation (which happens to depend on several os-level APIs such as
the VFS).
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
causes the rem timer callback pending check to run more often (every 1 ms
instead 10 ms). This is essential to met the timeout requirements of the
audio backend, which must be checked&run every 5ms.
This patch adjusts the interactive scenarios of the gems repository to
use the depot. This has three immediate benefits. First, once the depot
is populated with binary archives, the start time of the scenarios
becomes very quick because most dependency checks and build steps are
side-stepped. Second, the run scripts become more versatile. In
particular, run scripts that were formerly supported on base-linux only
(nit_fader, decorator, menu_view) have become usable on all base
platforms that have a 'drivers_interactive' package defined. Finally,
the run scripts have become much shorter.
Issue #2339
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.
This patch replaces the set-defaults command by a reset command, which
is needed to use the Lenovo x250 trackpoint. (original patch by
Christian Prochaska)
For asynchronously provided sessions, the parent has to maintain the
session state as long as the server hasn't explicitly responded to a
close request. For this reason, the lifetime of such session states is
bound to the server, not the client.
When the server responds to a close request, the session state gets
freed. The 'session_response' implementation does not immediately
destroy the session state but delegates the destruction to a client-side
callback, which thereby also notifies the client. However, the code did
not consider the case where the client has completely vanished at
session-response time. In this case, we need to drop the session state
immediately.
Fixes#2391
Originally, the spec files for less specific SPEC values were include
via the 'select_from_repositories' function. This implies that BASE_DIR
must always be present in the list of 'REPOSITORIES'. Otherwise the
spec files won't be found. By explicitly including sub specs from
'$(BASE_DIR)/mk', we lift this restriction.
This patch is required to build the OKL4 version of core from a source
archive. It avoids fetching source codes from BASE_DIR, and moves the
vpath wildcard for %.cc after all specific vpath definitins, in
particular those that are x86-specific. Without the latter change, core
would always end up using the generic version of 'platform_services.cc',
omitting the IO_PORT service from core.
The <build-dir>/bin/ directory used to contain symbolic links to the
unstripped build results. However, since the upcoming depot tool
extracts the content of binary archives from bin/, the resulting
archives would contain overly large unstripped binaries, which is
undesired. On the other hand, always stripping the build results is not
a good option either because we rely of symbol information during
debugging.
This patch changes the installation of build results such that a new
'debug/' directory is populated besides the existing 'bin/' directory.
The debug directory contains symbolic links to the unstripped build
results whereas the bin directory contains stripped binaries that are
palatable for packaging (depot tool) and for assembling boot images (run
tool).
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.
When creating a source archive for the USB driver, both the contrib and
Genode-specific source codes are merged into a single directory
structure. In this case, the original way of determining the Linux
source code to scan for #include directives would apply the scanning to
Genode-specific source codes too. This patch tightens the search
criterion such that only Linux source codes are processed.
This macro is implicitly pulled in by libc-setjmp (via the libc's
cdefs.h). However, apparently not all sources include <setjmp.h>.
Unfortunately, for sources that do, this change produces a
double-definition warning. We should fix it by removing the dependency
from the libc's setjmp.
File_system servers shall deny clients not matching a defined policy.
Servers shall also apply session root offset policy followed by a client
offset.
Fix#2365
Init's service forwarding functionality did not take the service type
into account when forwarding a session request. If a server provides
multiple services, e.g. fb_sdl that provides both "Input" and
"Framebuffer", the type of the forwarded session request did not always
correspond to the actually requested type.
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
The use of 'select_from_repositories' for locating the linker script for
dynamically-linked executables only works if 'BASE_DIR' appears in the
list of 'REPOSITORIES'. This is the case when using the build system in
the traditional way but it is not desired when building binary archives
of individual components.
This patch adjusts the run script in two ways:
It removes the reliance on init's formerly built-in resource-request
handling by increasing the RAM quota for the backdrop instances. Since
commit "init: explicit response to resource requests", init no longer
hands out slack memory automatically.
Second, it makes sure that the backdrop appears under the precise label
"backdrop" at nitpicker by facilitating init's label-rewriting feature.
Without explicitly setting the label to "backdrop", nitpicker observes
the label "backdrop -> backdrop" (the first part comes from init, the
second part comes from the nitpicker-session argument specified by
backdrop itself). However, the client is only considered as default
background if labeled as "backdrop" (see nitpicker's '_create_session')
implementation.
Issue #2352
The base class of Registered must provide a virtual destructor to enable
safe deletion with just a base class pointer. This requirement can be
lifted by using Registered_no_delete in places where the deletion
property is not needed.
Fixes#2331
Ldso now does not automatically execute static constructors of the
binary and shared libraries the binary depends on. If static
construction is required (e.g., if a shared library with constructor is
used or a compilation unit contains global statics) the component needs
to execute the constructors explicitly in Component::construct() via
Genode::Env::exec_static_constructors().
In the case of libc components this is done by the libc startup code
(i.e., the Component::construct() implementation in the libc).
The loading of shared objects at runtime is not affected by this change
and constructors of those objects are executed immediately.
Fixes#2332
With the current implementation resource requests are not automically
satisfied with slack quota by init. Therefore, this commit adapts RAM
quotas of autopilot scenarios to the actual demands.
An inline attribute mismatch in the gcc-4.9.2 source causes its
compilation to fail on modern gcc versions (verified with gcc 6.3.1,
but probably since gcc 5)
The patch is courtesy of the gcc-patches mailing list:
https://gcc.gnu.org/ml/gcc-patches/2015-08/msg00375.htmlFixes#2341
The test used to rely on init's formerly built-in policy of answering
resource requests with slack memory, if available. Since init no longer
responds to resource requests in an autonomous way, we use a dynamically
configured sub-init instance as runtime for the test. This instance, in
turn, is monitored and controlled such that resource requests are
result in quota upgrades. The monitoring component is implemented in
the same test-resource_request program as the test. Both roles are
distinguished by the "role" config attribute.
This is a follow-up to "init: explicit response to resource requests".
- use more upstream hm code
- add call to memory check as done in vbox4
- add in principle all vbox devices and drivers
- avoid null pointer during VM startup (patch reported to vbox-devel list)
- avoid endless loop in usb root hub
Issue #2338
This patch equips init with the ability to act as a server that forwards
session requests to its children. Session requests can be routed
depending of the requested service type and the session label
originating from init's parent.
The feature is configured by one or multiple <service> nodes hosted in
init's <config> node. The routing policy is selected by via the regular
server-side policy-selection mechanism, for example:
<config>
...
<service name="LOG">
<policy label="noux">
<child name="terminal_log" label="important"/>
</policy>
<default-policy> <child name="nitlog"/> </default-policy>
</service>
...
</config>
Each policy node must have a <child> sub node, which denotes name of the
server with the 'name' attribute. The optional 'label' attribute defines
the session label presented to the server, analogous to how the
rewriting of session labels works in session routes. If not specified,
the client-provided label is presented to the server as is.
Fixes#2247
This patch removes the formerly built-in policy of responding to
resource requests with handing out slack quota. Instead, resource
requests have to be answered by an update of the init configuration with
adjusted quota values.
Note that this patch may break run scripts that depend on init's
original policy. Those run scripts may be adjusted by increasing the
quota for the components that use to inflate their RAM usage during
runtime such that the specified quota suffices for the entire lifetime
of the component.
This patch destructs the environment sessions for the binary and the
dynamic linker along with the other environment sessions to avoid a
warning about reverting quota that occurs when attempting to close
these sessions too late.
This patch improves init's dynamic reconfigurability with respect to
adjustments of the RAM quota assigned to the children.
If the RAM quota is decreased, init withdraws as much quota from the
child's RAM session as possible. If the child's RAM session does not
have enough available quota, a resource-yield request is issued to
the child. Cooparative children may respond to such a request by
releasing memory.
If the RAM quota is increased, the child's RAM session is upgraded.
If the configuration exceeds init's available RAM, init re-attempts
the upgrade whenever new slack memory becomes available (e.g., by
disappearing other children).
Since init no longer provides public headers, we have to adjust the
existing users of this headers. The 'init/child_config.h' is used only
by GDB monitor. So the patch moves the header there as an interim fix.
The 'init/child_policy.h' is still used by a few components, so we have
to keep a trimmed-down version of it for now.
This patch enables init to apply changes of any server's <provides>
declarations in a differential way. Servers can in principle be extended
by new services without re-starting them. Of course, changes of the
<provides> declarations may affect clients or would-be clients as this
information is taken into account for the session routing.
This patch addresses the corner cases where an environment session
could not be routed, i.e., if an environment LOG log session is
routed to a non-existing child.
The optional 'version' attribute allows for the forced restart of a
child with an otherwise unmodified start node. The specified value is
also reflected in the state report.
This patch covers the resolution of the ROM route for child binaries
via the generic label-rewriting mechanics. Now, the <binary> node has
become merely sytactic sugar for a route like the following:
<start name="test"/>
<route>
<service name="ROM" unscoped_label="test">
<parent label="test-binary-name"/> </service>
...
</route>
...
</start>
A change of the binary name has an effect on the child's ROM route to
the binary and thereby implicitly triggers a child restart due to the
existing re-validation of the routing.
This patch extends the constructor of 'Local_connection' with an
optional 'label' argument, which was previously passed implicitly as
part of the 'args' argument. Keeping the label separate from 'args'
enables us to distinguish the client-specified label from a label that
resulted from a server-side label as it is used when rewriting a label
of an environment session (i.e., the binary name) in init's routing
policy. In principle, this patch eliminates the need for init's
explicite handling of the binary name via the '<binary>' node, or
at least allows us to simplity the binary-node handling.
With this check in place, one can safely construct an 'Xml_generator'
even if the report is disabled. This relieves the user of the reporter
from the need to distinguish enabled from disabled reports.
The initial ROMs (program and linker) are already attached to the region
map of a forked process and don't need to be obtained again from an
external ROM service when the 'Child' class asks for them. For the program
image, the local Noux ROM service already returned an invalid dataspace
capability, but not for the linker.
Instead of adding another 'magic' ROM name for the local ROM service,
this commit implements an 'empty' ROM service, which returns an
invalid dataspace for the initial ROMs.
Fixes#2272
The race may happen when element objects get destructed by another thread then
the thread handling the for_each loop. In this case it may happen that the
object is already destructed (left the ~Element destructor) but the thread
handling the loop touches the invalid memory afterwards (the Element lock).
detected during issue #2299Fixes#2320
Under certain timing conditions, the test would end up flushing the
input from the input filter in a nested way, which ultimately resulted
in lost input events of the outer nesting level. This patch eliminates
this corner case and thereby stabilizes the key-repeat test.
Transfer quota to the session local RAM session to react to the
Quota_exceeded exception properly.
The platform driver keeps a session local RAM session for each of its
clients that is used to allocate DMA memory. A client needs to transfer
some of its quota to the platform driver, which in return transfers this
quota to the session local RAM session. As it happens allocating memory
from a RAM session involves book keeping and in this case, where the
available quota in the session did not suffice and the request was only
a few KiB, the platform driver handled the exception wrongly and did not
transfer the quota.
This problem did not surface up to now because all drivers allocate DMA
memory in larger chunks and the book keeping overhead was of no
consequence as the initial quota transfer probably covered the overhead.
Fixes#2316.
Due to rounding in the timeout calculation it may happen that the timeout
stored in ms becomes 0, but actually some time (us or ns) are left to wait.
With threads on various priorities (vbox) this may end up in endless loops.
Fixes#2311
The file space demand for the object files when compiling core has grown.
Therefore, the ram_fs component runs out of memory and requests additional
memory from init. On OKL4, where the physical memory is limited by the
elfweaver bootstrap tool, there is no more slack memory after the donation
of 1G to noux.
* Increase test-thread count to trigger quota exceeding on all platforms
* Synchronize test-thread destruction, otherwise an half-destructed thread
object can lead to an error message of the thread to be destructed,
which causes a deadlock, when the destructed thread still holds the log lock
* Limit SMP settings for QEMU to x86 (Ref #2307)
The signal_1/2/3 objects (which are threads) are in destruction, but still
signals are send to them. When the signal arrive and the memory for the
signal_1/2/3 object is already invalid we operate on stale memory and all
the locking infrastructure of the Thread don't work anymore.
Be more robust, explicitly wait for the termination of the thread.
Issue #2284
Otherwise it may happend that the Guest tries to set the last stored
resolution from another run, which maybe is too large.
Up to now, everthing is fine, beside the fact that output changes are not
visible - which is odd and one things the VM came not up.
Issue #2306
that happened during early bootup.
The signal about input events may arrive before keyboard and mouse is set
(due wait_and_dispatch_one_signal called from a started pthread and ep still
not done with the initialisation)
Issue #2306
Previously we had configured the timer for the Panda ES with 700 MHz
CPU clock. But the Panda A6 that we use as reference now runs with
800 MHz.
Fixes#2308
Previously, on X86, the timer driver used the PIT with a maximum timeout
of 54 ms. Thus, the driver frequently interrupted the counters with
highest priority to update the timer. This is why we needed a higher
error tolerance as for ARM where the driver, once configured, can sleep
for the whole test timeout. Now, we use the kernel timer and the problem
seems to be exits no longer.
Ref #2304
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
By separating the plain MMIO access implementation from the generic bit
and offset logic of registers, we can now use the latter also with other
types of register access like I2C. The register and MMIO front-ends have
not changed due to the separation.
Ref #2196
* 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
The MIN_PSK_LENGTH constant was not adjusted to accommodate for the
semcantic change when switching from using the raw char array to using
the Genode::String class. The Genode::String::length() method includes
the terminating NUL byte while strlen() does not.
Fixes#2296.
With the commit "init: session-label rewriting", the stack usage
increased due to the handling of session-label strings as local
variables. The stack overrun occurred in the vmm scenario on
base-hw.
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
To select a different keyboard layout than the default 'en_us', override the
'language_chargen' function in your run script (after including
qt5_common.inc):
proc language_chargen { } { return "de" }
where "de" refers to the character map file
'repos/os/src/server/input_filter/de.chargen'
Issue #2264
This patch improves the accuracy of init's quota-saturation feature
(handing out all slack quota to a child by specifying an overly high RAM
quota for the child) and makes the RAM preserved by init configurable.
The preservation is specified as follows:
! <config>
! ...
! <resource name="RAM" preserve="1M"/>
! ...
! </config>
If not specified, init has a reasonable default of 160K (on 32 bit) and
320K (on 64 bit).
It seems that our buildbot has a problem with the TCL command 'string
cat'. In most cases it is not necessary anyway as we can use the ""
enclosure instead. It unfolds inline procedure calls and variables
automatically. We don't want to use "" only in cases where the literal
shall contain many " characters itself as it is the case for XML
configs. Then we use the 'append' command and a helper variable instead.
Ref #2193
It can happen that when Cpu_free_component is constructed the insertion
of the object through 'manage' succeeds for the EP put not for the pager
EP, which in turn raises an Out_of_meta_data exception. Because we are
within the constructor, the descstructor is not called, leading to a
dangling object pool entry for the EP.
issue #2289
This patch lets init apply configuration changes to a running scenario
in a differential way. Children are restarted if any of their session
routes change, new children can be added to a running scenario, or
children can deliberately be removed.
Furthermore, the new version of init is able to propagate configuration
changes (modifications of <config> nodes) to its children without
restarting them.
If 'close' does not call 'unlink' like 'shutdown', the Lxip_socket_dir
never gets destroyed and thus the socket server leaks resources like
RAM and ports.
Ref #2285
Our 'shutdown' implementation handles only the case that 'how' is 'RDWR'.
Thus, print an error and continue if a user calls it with another value.
Fixes#2285
If not dissolved in ~Entrypoint, the signal proxy is found within NOVA's
and FOC's object pool upon Rpc_entrypoint destruction. This leads to a
deadlock because the signal proxy is destructed before the RPC EP.
issue #2284
This patch ensures that the POLICY::release is called whenever the
session creation aborted with an exception. In the original version, an
exception like 'Quota_exceeded' caused a single-session root interface
to deny subsequent session requests.
If 'Libc::Kernel::resume:all()' is called from a non-main thread, send a
signal to unblock the main thread from 'wait_and_dispatch_one_signal()'.
Fixes#2283
Change metadata before submitting a packet. If the submitting thread is a
pthread, the metadata may be immediately change by the signal handler running
in the context of the entrypoint thread.
This patch enhances the 'Child' and 'Child_policy' with the ability to
separate the different steps of bootstrapping children. If the
'Child_policy::initiate_env_sessions()' returns false, the child's
environment sessions remain unrouted at construction time. This way,
child objects for many children can be initialized to a state that
allows the children to represent services for other children. Therefore,
session routing can be applied before any child executes.
At this stage, the environment RAM sessions of all children can be
created. Note that this step still has the limitation that RAM sessions
are generally expected to be provided by either the parent or a local
service.
Once all children are equipped with RAM, they can in principle receive
session-quota donations. Hence, all other environment sessions can now
be arbitrarily routed and initiated.
Once the environment of a child is complete, the child's process and
initial thread is created.
This patch improves the accounting for the backing store of
session-state meta data. Originally, the session state used to be
allocated by a child-local heap partition fed from the child's RAM
session. However, whereas this approach was somehow practical from a
runtime's (parent's) point of view, the child component could not count
on the quota in its own RAM session. I.e., if the Child::heap grew at
the parent side, the child's RAM session would magically diminish. This
caused two problems. First, it violates assumptions of components like
init that carefully manage their RAM resources (and giving most of them
away their children). Second, if a child transfers most of its RAM
session quota to another RAM session (like init does), the child's RAM
session may actually not allow the parent's heap to grow, which is a
very difficult error condition to deal with.
In the new version, there is no Child::heap anymore. Instead, session
states are allocated from the runtime's RAM session. In order to let
children pay for these costs, the parent withdraws the local session
costs from the session quota donated from the child when the child
initiates a new session. Hence, in principle, all components on the
route of the session request take a small bite from the session quota to
pay for their local book keeping
Consequently, the session quota that ends up at the server may become
depleted more or less, depending on the route. In the case where the
remaining quota is insufficient for the server, the server responds with
'QUOTA_EXCEEDED'. Since this behavior must generally be expected, this
patch equips the client-side 'Env::session' implementation with the
ability to re-issue session requests with successively growing quota
donations.
For several of core's services (ROM, IO_MEM, IRQ), the default session
quota has now increased by 2 KiB, which should suffice for session
requests to up to 3 hops as is the common case for most run scripts. For
longer routes, the retry mechanism as described above comes into effect.
For the time being, we give a warning whenever the server-side quota
check triggers the retry mechanism. The warning may eventually be
removed at a later stage.
This patch equips init with the ability to report its internal state in
the form of a "state" report. This feature can be enabled by placing a
'<report>' node in init's configuration.
The report node accepts the following arguments (with their default
values):
'delay_ms="100"': specifies the number of milliseconds to wait before
producing a new report. This way, many consecutive state changes -
like they occur during the startup - do not result in an overly
large number of reports but are merged into one final report.
'buffer="4K"': the maximum size of the report in bytes. The attribute
accepts the use of K/M/G as units.
'init_ram="no"': if enabled, the report will contain a '<ram>' node
with the memory stats of init.
'ids="no"': supplement the children in the report with unique IDs, which
may be used to infer the lifetime of children accross configuration
updates in the future;
'requested="no"': if enabled, the report will contain information about
all session requests initiated by the children.
'provided="no"': if enabled, the report will contain information about
all sessions provided by all servers.
'session_args="no"': level of detail of the session information
generated via 'requested' or 'provided'.
'child_ram="no"': if enabled, the report will contain a '<ram>' node
for each child based on the information obtained from the child's RAM
session.
Issue #2246
This method is a hook to enable a runtime to respond to state changes.
In particular, in init this hook is used to trigger the generation of a
new state report, if configured.
Furthermore, the patch introduces the 'generate_client_side_info' and
'generate_server_side_info' methods to the 'Session_state', which
generates an XML representation of the session states to appear in
reports produced by init.
Issue #2246
Normally, the platform driver helpers adapt the global run variables directly
via append. But the introduction of a more elegant run script style, that
incorporates dependent strings inline may be a good idea. Thus, we need the
backends of the helpers available as functions that return their string rather
than appending it.
The old interface still exists and uses the new interface as backend.
Ref #2193
The 'server_ip' and 'server_port' attributes for 'lxip/udp_client' and
'lwip/http_clnt' as well as the 'port' attribute for 'lxip/udp_echo' and
'lwip/http_srv_static' are not directly libc-related so they should not
live in the libc tag but in the config tag of the component.
Ref #2193
This patch enhances init with the support for rewriting session labels
in the target node of a matching session route. For example, a Noux
instance may have the following session route for the "home" file
system:
<route>
<service name="File_system" label="home">
<child name="rump_fs"/>
</service>
...
</route>
At the rump_fs file-system server, the label of the file-system session
will appear as "noux -> home". This information may be evaluated by
rump_fs's server-side policy. However, when renaming the noux instance,
we'd need to update this server-side policy.
With the new mechanism, the client's identity can be hidden from the
server. The label could instead represent the role of the client, or a
name of a physical resource. For example, the Noux route could be
changed to this:
<route>
<service name="File_system" label="home">
<child name="rump_fs" label="primary_user"/>
</service>
...
</route>
When the rump_fs receives the session request, it is presented with the
label "primary_user". The fact that the client is "noux" is not taken
into account for the server-side policy selection.
Issue #2248
The new return value of 'resolve_session_request' allows the child
policy to define the label used as the policy selector at the server.
Because this patch introduces the distinction of the child-provided
label from the label as presented to the server along with the session
request, the latter is now handled as a dedicated 'Session_state'
argument.
Issue #2248
This commit includes changes to the Nic::Session_component interface.
We now pass the entire env to the component instead of only ram, rm and
the ep because we need the env to open connections from within the
Session_component implemenation. So far only the cadence_gem driver
needs this, though.
Issue #2280.
Libc components cannot use regular calls to select() as this may suspend
their execution. In this case incoming RPCs will be deferred until
select() returns and the component returns to the entrypoint dispatch
loop. The Libc::Signal_handler solves this problem with a its select()
that either returns the currently ready file descriptors immediately or
calls the registered handler function during libc resume.
Now, the libc kernel supports to execute application code from all RPC
functions not only Component::construct(). This is enabled by the
Libc::with_libc() scope function.
This commit extends an easy-to-use mechanism to allow Genode component
code to enter/leave the libc application context. This is needed
whenever low-level component code (like signal handlers or RPC
functions) need to interact with potentially blocking libc I/O
functions.
Please note that this commit contains the API-level design only. The
actual context switching code 'execute_in_application_context' is
missing.
The socket file system can be configured in the "socket" attribute of
the libc config node like follows.
<vfs> <dir name="socket"> <fs/> </dir> </vfs>
<libc ... socket="/socket"/>
This configures the socket file system libc backend to access files in
"/socket" for socket operations.
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'.
This patch enhances init with the ability to route individual
environment sessions. Prior this patch, environment sessions could be
routed only by an all-encompassing '<service>' node that would match
both child-initiated and environment sessions.
In contrast to the existing 'label', 'label_prefix', and 'label_suffix'
attributes of '<service>' nodes, which are always scoped with ther name
of the corresponding child, the 'unscoped_label' allows the definition
of routing rules for all session requests, including init's requests for
the child's environment sessions. For example, to route the ROM session
requests for a child's dynamic linker, the following route would match:
<route>
<service name="ROM" unscoped_label="ld.lib.so"> ... </service>
</route>
Issue #2215
When a directory gets destructed it dissolves the handles of each contained file
but the acknowledgement might be still in-flight. If we finally receive it,
it leads to an Unknown_id exception on the Handles ID Space in 'handle_ack'.
Now we catch it, print a warning, and go on.
This patch adds the handling of 'CHARACTER' events as emitted by the
input-filter's character generator (<chargen>). To avoid interpreting
press/release events twice (at the input filter and by the terminal's
built-in scancode tracker), the terminal's scancode tracker can be
explicitly disabled via <config> <keyboard layout="none"/> </config>.
In the future, the terminal's built-in scancode tracker will be
removed.
The use of the terminal with the input filter is illustrated by the
'terminal_echo.run' script.
Issue #2264
The input_filter is the successor of the input_merger. In addition to
merging input streams, the component applies several forms of input
transformations such as the application of keyboard layouts.
Issue #2264
Character events are created via a dedicated 'Event' constructor that
takes an 'Event:Utf8' object as argument. Internally, the character is
kept in the '_code' member. The 'Utf8' value can by retrieved by the
recipient via the new 'utf8' method.
Issue #2264
A binary file may be a temporary Vim .swp file when examining contrib
sources. The commit prevents build errors like
.../repos/dde_linux/lib/mk/lxip_include.mk:29:
target '.../x86_64/var/libcache/lxip_include/include/include/include/Binary'
given more than once in the same rule
.../repos/dde_linux/lib/mk/lxip_include.mk:29:
target '.../x86_64/var/libcache/lxip_include/include/include/include/file'
given more than once in the same rule
...
A Signal_handler may schedule a hook function that is executed after the
signal handler returned. This can be used if the hook function may
trigger a (nested) signal handler by means of
wait_and_dispatch_one_signal(). Otherwise, an occurrence of the same
signal that triggered the original signal handler results in a dead lock
just before calling the nested handler (due to the Signal_context
destruction lock).
The read-ready packet informs the server that the client wants to be
notified if a handle becomes readable. When becoming readable, the
server acknowledges packet and the client may queue a read requests
accordingly.
The i.MX53 Framebuffer driver doesn't come up on on Fiasco.OC because the Platform
driver isn't allowed to access essential devises like the SRC or the Fuses. This is
most likely due to the kernel not configuring the CSU appropriately.
Ref #2268
broken due to changes of
libc: API transition
Issue #1987
For now provide a initial memory buffer for allocation of static
constructors and of malloc calls out of the libc during early
libc initialization until actual vbox code is executed having the Env
pointer.
This change introduces a Genode specific init function, which sets the
backend allocator used by jent_zalloc/zfree(). As consequence the
library can solely be used by native Genode components, direct libc
usage is not supported.
Fixes#2274.
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 hook allows the export of the allocator's state by a derrived
class. I.e., the final state of the allocator used for bootstrapping
core.
Ref #2092
This patch eliminates the need for a global allocator by passing the
parent-service registry as argument to the 'Slave::Policy' constructor.
Fixes#2269
The support has two parts. First, a VFS plugin now gets passed an
I/O-response handler callback on construction, which informs users of the
VFS that an I/O event occurred. This enables, for example, the libC to
check if blocking read can be completed. Further, the VFS file I/O
interface provides now functions for suspendable reads, i.e.,
queue_read() and complete_read().
Replacing the node lookup table with an Id_space removes the
limit on open handles per session and allows mutal associativity
between File_system handles and local VFS handles.
Fix#2221
The test now forks twice - the parent forks a child and the child itself
forks a grand child. Both, parent and child, wait for termination of
their forked process with waitpid(). Additionally, the run script now
checks for exit of the parent (not any noux process).
First, calls to manage and dissolve signal contexts now check if the
signal receiver was constructed. There is a small window during suspend
where it is destructed before reconstructed again.
Last, we ensure that processing of incoming signal was deblocked by the
suspend signal before entering the suspend operation. This way we ensure
already queued signal are handled.
The block file system wrongly modified the seek offset during a
read-modify-write operation that is required for sub-block-size
requests. This led to problems whenever such write requests spanned
multiple blocks and thereby were handled in multiple iterations.
Fixes#2262
This test reproduces an issue of the VFS block file system when the
underlying block device has a coarser granularity than the block
requests issued by the VFS client. I.e., if the underlying block device
has a block size of 4K, writing a sequence of (non-4K-aligned) 512 blocks
that crosss a 4K boundary corrupts the data on the block device.
Issue #2262
The new utility at 'os/static_parent_services.h' allows the creation of
a registry of parent services at compile time and thereby eliminates the need
for dynamic memory allocations whenever the set of services is known at
compile time as is the case for most uses of 'Slave::Policy'. The commit
showcases the utility in the bomb test.
This commit enables compile-time warnings displayed whenever a deprecated
API header is included, and adjusts the existing #include directives
accordingly.
Issue #1987
On Odroid XU the SD card driver comes up and finds a card but for card
access it seems that we would need a platform driver like on Arndale.
On imx_53, the first SDHCI MMIO access faults. This is likely due to the
AIPSTZ memory bridge. On HW, we initialize the AIPSTZ in the kernel, but
when I tried doing that in the platform driver instead, the first AIPSTZ
MMIO access faults ^^ So I gave up for now and removed support.
Fixes#2259
Parse ``<env key="..." value=".."/>`` nodes from the config ROM and
populate a list at the 'genode_envp' and 'environ' symbols.
Test script at run/libc_getenv.
Fix#2236
For all tests
* use Component::construct instead of main
* use new connection constructors with env argument
* use log instead of printf
For some tests
* replace signal receivers with signal handlers
* replace global static variables with Main class members
* remove unnecessary multithreading
* model test steps as classes that are independent from each other and managed
by Main as constructibles
* use references instead of pointers and exceptions instead of error codes
* use Attached_* helpers intead of doing attach/detach manually
* use helpers like String, Id_space, Registry instead of arrays and lists
* make the run script suitable for automated execution and conclusion
Ref #1987
In the past, the Genode::destroy, that is called by the RAM-FS-chunk destructors,
issued Allocator::free instead of the C++ delete. Therefore it was possible to
use the size argument of Allocator::free for the allocation tracker in the
RAM-FS-chunk test. Nowadays, we have to keep track of the allocation sizes
ourselves because delete doesn't hand over the size.
Ref #1987
The FB Block Adapter in os/src/test visualizes a block session via a
Framebuffer session. As far as I can see, it is not a test but rather
the base for a bump-in-the-wire component. However, for this role it
currently lacks a Block back-end. As it also would have to be updated to
use the new base API I removed it instead, leaving only its git
history as inspiration if someone needs such a component in the future.
Fixes#2245
Ref #1987
lesskey and lessecho missed the declaration of ${LIBS} on the compiler
command line, which ended up in unusable programs.
> file noux-pkg/less/lesskey.broken
noux-pkg/less/lesskey.broken: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter *empty*, not stripped
> file noux-pkg/less/lesskey
noux-pkg/less/lesskey: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter ld.lib.so, not stripped
The issue was identified because -O0 builds broke with
ld: lesskey: The first section in the PT_DYNAMIC segment is not the .dynamic section
Unfortunately, this simple fix renders both tools also dependent to libm
and ncurses which they don't use.
This streamlines the Genode-specific interface for both 32-bit and
64-bit architectures and fixes dynamic-linking issue with the rump
VFS due to differing size_t types.
This function returns the information whether the used platform relies
on USB HID for interactive scenarios by default as is the case for most
ARM platforms. In contrast, for x86 the USB driver can be omitted because
we can use the PS/2 driver (that is readily available in repos/os/).
If the detach address is not the beginning of the region, one gets:
"virtual void Genode::Allocator_avl_base::free(void*): given
address (0x180e0) is not the block start address (0x18000)"
Instead, print an explicit warning in front of the detach call.
Cleaning up LWIP when returning from the main function sporadically
leads to endless errors "Error: sys_arch_mbox_fetch: unknown exception
occured!". We let the client sleep forever at the end of its main function
to prevent tests from failing due to a flooded log.
Reg #2193
* get rid of printf
* use exceptions instead of error codes
* use Id_space instead of the individual block device registry
* use Cstring instead of char const*
* move method definitions > 1 line to .cc files
* rename Block Block_driver and Serial Serial_driver to avoid name clashes
with the Genode namespace and thereby simplify the code
* use lambdas for Block device lookup and apply
* switch to the Component framework
* don't use env(), config(), ... and hand over env to each connection
* use Attached_mmio and Attached_rom/ram_dataspace instead of manual
solutions
Fixes#2223
The init component used to create the CPU/RAM/PD/ROM sessions (the child
environment) for its children by issuing session requests to its parent,
which is typically core. This policy was hard-wired. This patch enables
the routing of the environment sessions of the children of init
according to the configured routing policy.
Because there is no hard-wired policy regarding the environment sessions
anymore, routes to respective services must be explicitly declared in
the init configuration. For this reason, the patch adjusts several run
scripts in this respect.
This patch removes the outdated '<if-args>' special handling of session
labels. The '<if-args>' feature will eventually be removed completely
(ref #2250)
Issue #2197
Issue #2215
Issue #2233
Issue #2250
This patch changes the 'Xml_node_label_score' to regard an empty
label_prefix or label_suffix as a match instead of a conflict. Until
now, there was no use case for an empty label_prefix. But with init's
new ability to route environment sessions, an empty prefix denotes any
child-initiated session (as oposed to an parent-initiated environment
session).
Issue #2215
Issue #2233
This patch fixes a problem that unsurfaced by the commit "menu_view: API
transition", which changed the class layout of the 'Png_image' so that
the 'Read_struct' pointer is no longer equal to the 'Png_image' pointer.
This commit addresses the situation where an environment session
outlives the session-providing service. In this case, the env session
got already invaidated at the destruction time of the server. However,
the underlying session-state structure continues to exist until the
client is destructed. During the eventual destruction of such a dangling
environment session, we have to be careful not to interact with the
no-longer existing service.
Ref #2197
This patch addresses the corner case of destructing a child that
provides an enviroment session to another child. Before this patch,
this situation could result in an infinite loop.
The problem was introduced as a side effect of issue #2197 "base: apply
routing policy to environment sessions".
This patch re-enables the launchpad to start multiple instances of the
same program. Without it, launchpad wrongly requests the binary ROM with
the child's unique name as label. The lookup of the first instance
solely succeeds because the unique name equals the binary name.
To better support non-blocking terminal components, let the
'Terminal::Session::write()' function return the number of bytes
actually written.
Fixes#2240
The session-control mechanism is based on the way how sessions are
labeled. In #2171, we changed the labeling to be more strict. In
particular, label-less sessions do no longer exist.
Unfortunately, nitpicker and the window manager still handled the former
weaker labeling, which ultimately led to a situation where any
session-control argument would mismatch. The behavior could be observed
in the launcher.run script where a click on the subsystem button would
not focus the clicked-on subsystem. With the patch, the scenario works
again as expected.
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 patch removes the dependency of the deprecated Genode API,
fixes the coding style, and removes the "random" file system
(superseded by the VFS plugin mechanism).
Ref #1987
Merge the platform-specific files and classes (they merely aggregated
themselves) so that each platform provides merely one class
Sd_card::Driver. Also, the Sd_card::Driver_base class is introduced for
the generic parts of Sd_card::Driver.
Ref #2206
Most implementations use a Signal_handler now to acknowledge the packet
instead of waiting for the transfer completion. The exceptions to that are
the non-DMA implementations for RPI and PL180
Ref #2206
In addition to that we now busy wait, i.e. poll, for interrupts
instead of using the IRQ session. That is fine because interrupts
were only used while configuring the HDMI over I2C and are not used
while normal operation.
Issue #1987.
Libc::Env is the Genode::Env interface extended to cover access
to the XML content of the 'config' ROM and a VFS instance. This
deduplicates the burden of components to attain and manage
these resources.
Fix#2217
Ref #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.
Ubuntu provides position independent shared objects for libraries, e.g.,
libsdl1.2-dev. To appropriatly link it to Genode, the linker flag
'-no-pie' has to be added to the make file.
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
On a 64-bit system, enabling the OpenSSL NIST 64-bit optimization should
result in considerable speed improvements when using curves: NIST-P224,
NIST-P256, and NIST-P521. Additionally it avoids that Tor complains
about having an OpenSSL that lacks this feature.
Ref #2193
These functions are marked as always inline through the 'SELF_RELOC' macro. This
became necessary because on riscv functions calls are performed through the
global offset table, which is not initialized at this point.
Fixes#2203
This patch makes the benefit of the recently introduced unified Genode
ABI available to developers by enabling the use of multiple kernels from
within a single build directory. The create_builddir tool has gained a
new set of kernel-agnostic platform arguments such as x86_32, or panda.
Most build targets within directories are in principle compatible with
all kernels that support the selected hardware platform. To execute a
scenario via the run tool, one has to select the kernel to use by
setting the 'KERNEL' argument in the build configuration
(etc/build.conf). Alternatively, the 'KERNEL' can be specified as
command-line argument of the Genode build system, e.g.:
make run/log KERNEL=nova
This allows us to easily switch from one kernel to another without
rebuilding any Genode component except for the very few kernel-specific
ones.
The new version of the 'create_builddir' tool is still compatible with
the old version. The old kernel-specific build directories can still be
created. However, those variants will eventually be removed.
Note that the commit removes the 'ports-foc' repository from the
generated 'build.conf' files. As this is only meaningful for 'foc',
I did not want to include it in the list of regular repositories (as
visible in a 'x86_32' build directory). Hence, the repository must
now be manually added in order to use L4Linux.
Issue #2190
This patch removes the manually maintained symbol map from the dynamic
linker. This way, the symbol map stays in sync with the ABI and - more
importantly - no longer uses wildcards. So the symbols exported by the
dynamic linker are strictly limited by the ABI.
Issue #2190
Previously, if a packet should be routed to a domain that had no interface
connected, the NIC router only printed "Unroutable packet". Technically,
this was wrong as an unavailable interface doesn't mean that the routing
failed. Now it gives an error "no interface connected to domain".
Ref #2193
The main window must be visible before avplay or a framebuffer filter
requests the framebuffer session which goes to Nitpicker, because the
parent view of the new Nitpicker view is part of the
QNitpickerPlatformWindow object, which is created when the main window
becomes visible. If this object does not exist yet, a page fault occurs.
Fixes#2187
This patch changes the child-construction procedure to allow the routing
of environment sessions to arbitrary servers, not only to the parent.
In particular, it restores the ability to route the LOG session of the
child to a LOG service provided by a child of init. In principle, it
becomes possible to also route the immediate child's PD, CPU, and RAM
environment sessions in arbitrary ways, which simplifies scenarios that
intercept those sessions, e.g., the CPU sampler.
Note that the latter ability should be used with great caution because
init needs to interact with these sessions to create/destruct the child.
Normally, the sessions are provided by the parent. So init is safe at
all times. If they are routed to a child however, init will naturally
become dependent on this particular child. For the LOG session, this is
actually not a problem because even though the parent creates the LOG
session as part of the child's environment, it never interacts with the
session directly.
Fixes#2197
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
The header is foc-specific. It used to shadow the generic one provided
by the base repository, which contradicts with the kernel-agnostic
Genode API. Hence, it had to be moved to a foc-specific location.
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
By not placing the sysio buffer (16 KiB) on the stack, we can call
'noux_syscall' from the initial thread. This is needed to issue fork
from the suspend callback, which is executed by the initial thread.
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 main thread does no longer execute application code. It is solely
responsible for the initialization of the component's entrypoint and for
retrieving asynchronous notifications. Since the stack usage is no
longer dependent on application-specific code, we can significantly
shrink it to reduce the memory footprint of components. In the worst
case - should the stack overrun - we would observe a page fault because
the stack is placed in the stack area, surrounded by guard pages.
This patch replaces the former machine-word-dependent default stack size
by the fixed value of 64 KiB which should suffice for components on both
32 and 64 bit. Previously, the default stack size on 64 bit was 128 KiB,
which is wasteful. If a component needs more stack than 64 KiB, it can
specify a custon stack size by implementing 'Component::stack_size'.
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.
