Commit Graph

10 Commits

Author SHA1 Message Date
Stefan Kalkowski c3d4802ac8 hw: re-implement lazy FPU context switch
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
2016-01-26 16:20:38 +01:00
Stefan Kalkowski 7aff1895bf hw: enable SMP for ARM Cortex A9
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 #1312
Fix #1807
2016-01-26 16:20:18 +01:00
Stefan Kalkowski e05d26567d hw: make 'smp' property an aspect (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.
2016-01-15 16:42:12 +01:00
Stefan Kalkowski e61a3db30d hw: separate function declaration/implementation
Move kernel object functions from its headers to compilation units,
thereby reducing the kernel's text section, cache, and TLB footprint.

Fix #1492
2015-05-06 10:55:23 +02:00
Martin Stein 955977b516 hw: syscall for changing a threads physical quota
This commit also extends the "cpu_scheduler" test to test the back-end of the
new syscall.

Ref #1464
2015-04-23 16:51:33 +02:00
Stefan Kalkowski 8e2b4d6f45 hw: extend kernel interrupt class
The generalization of interrupt objects in the kernel and the use of
C++ polymorphism instead of explicitely checking for special interrupts
within generic code (Cpu_job::_interrupt) enables the registration of
additional interrupts used by the kernel, which are needed for specific
aspects added to the kernel, like ARM hardware virtualization interrupts.

* Introduce generic base class for interrupt objects handled by the kernel
* Derive an interrupt class for those handled by the user-land
* Implement IPI-specific interrupt class
* Implement timer interrupts using the new generic base class

Ref #1405
2015-02-27 11:43:56 +01:00
Martin Stein 5dea0b40aa hw: don't use ARM CPU-state stuff in generic code
Fixes #1404
2015-02-16 13:40:36 +01:00
Martin Stein d704563453 hw: helping on IPC
On base-hw, each thread owns exactly one scheduling context for its
whole lifetime. However, introducing helping on IPC, a thread might get
executed on scheduling contexts that it doesn't own. Figuratively
spoken, the IPC-helping relation spans trees between threads. These
trees are identical to those of the IPC relation between threads. The
root of such a tree is executed on all scheduling contexts in the tree.
All other threads in the tree are not executed on any scheduling context
as long as they remain in this position. Consequently, the ready-state
of all scheduling contexts in an IPC-helping tree always equals the
state of the root context.

fix #1102
2014-12-19 13:58:47 +01:00
Martin Stein 8f9355b360 thread API & CPU session: accounting of CPU quota
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
2014-11-28 12:02:37 +01:00
Martin Stein b8ba3a7a22 hw: rename Kernel::Processor Kernel::Cpu
Kernel::Processor was a confusing remnant from the old scheme where we had a
Processor_driver (now Genode::Cpu) and a Processor (now Kernel::Cpu).
This commit also updates the in-code documentation and the variable and
function naming accordingly.

fix #1274
2014-11-28 12:02:35 +01:00