Avoids the need to have per IRQ a thread that blocks synchronously for next
interrupt. Now a thread may wait for multiple IRQs as other signals
simultaneously.
In core no threads are required anymore for IRQs/MSI - the clients (either
the pci_drv or in case of MSI the driver) gets the IRQ delivered directly as
a ordinary Genode signal.
Useful since #1216 and #1487 is now available.
Commit applies feature of #1446 also to IRQ/MSIs.
On NOVA, a Genode thread currently cannot destroy itself by destroying its
own 'Thread' object, because in 'Thread_base::_deinit_platform_thread()'
it cannot call 'Cpu_session::kill_thread()' anymore after it has revoked
its own UTCB.
As solution, the revocation of the UTCB can be delayed until its location
in the context area is needed by a new thread.
Fixes#1505
On seL4, we need to convert untyped memory to page frames before being
able to use it as normal memory. There already exists the hook function
'_export_ds' that is principally suitable for such tasks. It is
currently solely used on Linux where we have to create a file for each
dataspace. To make the hook useful also for seL4, we need to call
_export_ds prior _clear_ds. Otherwise, we would try to clear memory that
is still untyped.
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
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
The linker scripts use to fill alignment gaps within the text section
with the magic value 0x90909090, which correponds to the opcodes of four
nop instructions on x86. This patch removes this value because it
apparently solves no problem. If, for some reason (e.g., due to a dangling
pointer) a thread executes instructions within alignment paddings, NOP
instructions are not any better than any other instruction. The program
will eventually execute the instructions after the padding, which is
most likely fatal. It would be more reasonable to fill the padding with
the opcode of an illegal instruction so that such an error can be
immediately detected. That said, I cannot remember a single instance,
where the fill value has helped us during debugging.
Even if the mechanism served a purpose on x86, it is still better to
remove it because it does not equally work on the other architectures
where the linker scripts are used. I.e., on ARM, the opcode 0x90909090
is not a NOP instruction.
The commit
- fixes the syscall bindings for using portal permissions
- revokes PT_CTRL permission after pager in core set local badge name
- revokes PT_CTRL permission after server entrypoint code set local badge name
Fixes#1335
If the debug branch of the nova kernel is used, following messages are printed
by the kernel during vCPU setup phase:
[0] overmap attempt OBJ - tree - ...
Fixes#1324
In the init configuration one can configure the donation of CPU time via
'resource' tags that have the attribute 'name' set to "CPU" and the
attribute 'quantum' set to the percentage of CPU quota that init shall
donate. The pattern is the same as when donating RAM quota.
! <start name="test">
! <resource name="CPU" quantum="75"/>
! </start>
This would cause init to try donating 75% of its CPU quota to the child
"test". Init and core do not preserve CPU quota for their own
requirements by default as it is done with RAM quota.
The CPU quota that a process owns can be applied through the thread
constructor. The constructor has been enhanced by an argument that
indicates the percentage of the programs CPU quota that shall be granted
to the new thread. So 'Thread(33, "test")' would cause the backing CPU
session to try to grant 33% of the programs CPU quota to the thread
"test". By now, the CPU quota of a thread can't be altered after
construction. Constructing a thread with CPU quota 0 doesn't mean the
thread gets never scheduled but that the thread has no guaranty to receive
CPU time. Such threads have to live with excess CPU time.
Threads that already existed in the official repositories of Genode were
adapted in the way that they receive a quota of 0.
This commit also provides a run test 'cpu_quota' in base-hw (the only
kernel that applies the CPU-quota scheme currently). The test basically
runs three threads with different physical CPU quota. The threads simply
count for 30 seconds each and the test then checks wether the counter
values relate to the CPU-quota distribution.
fix#1275
The memory barrier prevents the compiler from changing the program order
of memory accesses in such a way that accesses to the guarded resource
get outside the guarded stage. As cmpxchg() defines the start of the
guarded stage it also represents an effective memory barrier.
On x86, the architecture ensures to not reorder writes with older reads,
writes to memory with other writes (except in cases that are not
relevant for our locks), or read/write instructions with I/O
instructions, locked instructions, and serializing instructions.
However on ARM, the architectural memory model allows not only that
memory accesses take local effect in another order as their program
order but also that different observers (components that can access
memory like data-busses, TLBs and branch predictors) observe these
effects each in another order. Thus, a correct program order isn't
sufficient for a correct observation order. An additional architectural
preservation of the memory barrier is needed to achieve this.
Fixes#692
The weak implementation was added for quite special purposes years ago
and is no longer needed. On the other hand, the weak attribute does not
help if the implementation ends up in a shared library, which first
resolves symbols locally before asking ldso (that includes the acutal
thread library) *shiver*
When a page fault cannot be resolved, the GDB monitor can get a hint about
which thread faulted by evaluating the thread state object returned by
'Cpu_session::state()'. Unfortunately, with the current implementation,
the signal which informs GDB monitor about the page fault is sent before
the thread state object of the faulted thread has been updated, so it
can happen that the faulted thread cannot be determined immediately
after receiving the signal.
With this commit, the thread state gets updated before the signal is sent.
At least on base-nova it can also happen that the thread state is not
accessible yet after receiving the page fault notification. For this
reason, GDB monitor needs to retry its query until the state is
accessible.
Fixes#1206.
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082
