Additional arch specific interfaces to handle memory domain
destroy and single partition removal.
Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
Additional arch specific interfaces to handle memory domain
destroy and single partition removal.
Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
Currently this is defined as a k_thread_stack_t pointer.
However this isn't correct, stacks are defined as arrays. Extern
references to k_thread_stack_t doesn't work properly as the compiler
treats it as a pointer to the stack array and not the array itself.
Declaring as an unsized array of k_thread_stack_t doesn't work
well either. The least amount of confusion is to leave out the
pointer/array status completely, use pointers for function prototypes,
and define K_THREAD_STACK_EXTERN() to properly create an extern
reference.
The definitions for all functions and struct that use
k_thread_stack_t need to be updated, but code that uses them should
be unchanged.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Add the following application-facing memory domain APIs:
k_mem_domain_init() - to initialize a memory domain
k_mem_domain_destroy() - to destroy a memory domain
k_mem_domain_add_partition() - to add a partition into a domain
k_mem_domain_remove_partition() - to remove a partition from a domain
k_mem_domain_add_thread() - to add a thread into a domain
k_mem_domain_remove_thread() - to remove a thread from a domain
A memory domain would contain some number of memory partitions.
A memory partition is a memory region (might be RAM, peripheral
registers, flash...) with specific attributes (access permission,
e.g. privileged read/write, unprivileged read-only, execute never...).
Memory partitions would be defined by set of MPU regions or MMU tables
underneath.
A thread could only belong to a single memory domain any point in time
but a memory domain could contain multiple threads.
Threads in the same memory domain would have the same access permission
to the memory partitions belong to the memory domain.
The memory domain APIs are used by unprivileged threads to share data
to the threads in the same memory and protect sensitive data from
threads outside their domain. It is not only for improving the security
but also useful for debugging (unexpected access would cause exception).
Jira: ZEP-2281
Signed-off-by: Chunlin Han <chunlin.han@linaro.org>
* Instead of a common system call entry function, we instead create a
table mapping system call ids to handler skeleton functions which are
invoked directly by the architecture code which receives the system
call.
* system call handler prototype specified. All but the most trivial
system calls will implement one of these. They validate all the
arguments, including verifying kernel/device object pointers, ensuring
that the calling thread has appropriate access to any memory buffers
passed in, and performing other parameter checks that the base system
call implementation does not check, or only checks with __ASSERT().
It's only possible to install a system call implementation directly
inside this table if the implementation has a return value and requires
no validation of any of its arguments.
A sample handler implementation for k_mutex_unlock() might look like:
u32_t _syscall_k_mutex_unlock(u32_t mutex_arg, u32_t arg2, u32_t arg3,
u32_t arg4, u32_t arg5, void *ssf)
{
struct k_mutex *mutex = (struct k_mutex *)mutex_arg;
_SYSCALL_ARG1;
_SYSCALL_IS_OBJ(mutex, K_OBJ_MUTEX, 0, ssf);
_SYSCALL_VERIFY(mutex->lock_count > 0, ssf);
_SYSCALL_VERIFY(mutex->owner == _current, ssf);
k_mutex_unlock(mutex);
return 0;
}
* the x86 port modified to work with the system call table instead of
calling a common handler function. fixed an issue where registers being
changed could confuse the compiler has been fixed; all registers, even
ones used for parameters, must be preserved across the system call.
* a new arch API for producing a kernel oops when validating system call
arguments added. The debug information reported will be from the system
call site and not inside the handler function.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Based on work by Chunlin Han <chunlin.han@linaro.org>.
This defines the interfaces that architectures will need to implement in
order to support memory domains in either MMU or MPU hardware.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Now creating a thread will assign it a unique, monotonically increasing
id which is used to reference the permission bitfield in the kernel
object metadata.
Stub functions in userspace.c now implemented.
_new_thread is now wrapped in a common function with pre- and post-
architecture thread initialization tasks.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
This will be used by system call handlers to ensure that any memory
regions passed in from userspace are actually accessible by the calling
thread.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
In various places, a private _thread_entry_t, or the full prototype
were being used. Be consistent and use the same typedef everywhere.
Signen-off-by: Andrew Boie <andrew.p.boie@intel.com>
Historically, stacks were just character buffers and could be treated
as such if the user wanted to look inside the stack data, and also
declared as an array of the desired stack size.
This is no longer the case. Certain architectures will create a memory
region much larger to account for MPU/MMU guard pages. Unfortunately,
the kernel interfaces treat both the declared stack, and the valid
stack buffer within it as the same char * data type, even though these
absolutely cannot be used interchangeably.
We introduce an opaque k_thread_stack_t which gets instantiated by
K_THREAD_STACK_DECLARE(), this is no longer treated by the compiler
as a character pointer, even though it really is.
To access the real stack buffer within, the result of
K_THREAD_STACK_BUFFER() can be used, which will return a char * type.
This should catch a bunch of programming mistakes at build time:
- Declaring a character array outside of K_THREAD_STACK_DECLARE() and
passing it to K_THREAD_CREATE
- Directly examining the stack created by K_THREAD_STACK_DECLARE()
which is not actually the memory desired and may trigger a CPU
exception
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
One of the stack sentinel policies was to check the sentinel
any time a cooperative context switch is done (i.e, _Swap is
called).
This was done by adding a hook to _check_stack_sentinel in
every arch's __swap function.
This way is cleaner as we just have the hook in one inline
function rather than implemented in several different assembly
dialects.
The check upon interrupt is now made unconditionally rather
than checking if we are calling __swap, since the check now
is only called on cooperative _Swap(). The interrupt is always
serviced first.
Issue: ZEP-2244
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
The kernel tracks time slice usage with the _time_slice_elapsed global.
Every time the timer interrupt goes off and the timer driver calls
_nano_sys_clock_tick_announce() with the elapsed time, this is added to
_time_slice_elapsed. If it exceeds the total time slice, the thread is
moved to the back of the queue for that priority level and
_time_slice_elapsed is reset to zero.
In a non-tickless kernel, this is the only time _time_slice_elapsed is
reset. If a thread uses up a partial time slice, and then cooperatively
switches to another thread, the next thread will inherit the remaining
time slice, causing it not to be able to run as long as it ought to.
There does exist code to properly reset the elapsed count, but it was
only compiled in a tickless kernel. Now it is built any time
CONFIG_TIMESLICING is enabled.
Issue: ZEP-2107
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Fixes sparse warning:
CHECK <snip>/zephyr/kernel/thread.c
<snip>/zephyr/kernel/thread.c:184:20: error: symbol '_thread_entry' redeclared with different type (originally declared at <snip>/zephyr/kernel/include/nano_internal.h:43) - different modifiers
CC kernel/thread.o
Change-Id: I2223493cdf97c811c661773f8fd430e6c00cbaa0
Signed-off-by: Maciek Borzecki <maciek.borzecki@gmail.com>
Unline k_thread_spawn(), the struct k_thread can live anywhere and not
in the thread's stack region. This will be useful for memory protection
scenarios where private kernel structures for a thread are not
accessible by that thread, or we want to allow the thread to use all the
stack space we gave it.
This requires a change to the internal _new_thread() API as we need to
provide a separate pointer for the k_thread.
By default, we still create internal threads with the k_thread in stack
memory. Forthcoming patches will change this, but we first need to make
it easier to define k_thread memory of variable size depending on
whether we need to store coprocessor state or not.
Change-Id: I533bbcf317833ba67a771b356b6bbc6596bf60f5
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Adds event based scheduling logic to the kernel. Updates
management of timeouts, timers, idling etc. based on
time tracked at events rather than periodic ticks. Provides
interfaces for timers to announce and get next timer expiry
based on kernel scheduling decisions involving time slicing
of threads, timeouts and idling. Uses wall time units instead
of ticks in all scheduling activities.
The implementation involves changes in the following areas
1. Management of time in wall units like ms/us instead of ticks
The existing implementation already had an option to configure
number of ticks in a second. The new implementation builds on
top of that feature and provides option to set the size of the
scheduling granurality to mili seconds or micro seconds. This
allows most of the current implementation to be reused. Due to
this re-use and co-existence with tick based kernel, the names
of variables may contain the word "tick". However, in the
tickless kernel implementation, it represents the currently
configured time unit, which would be be mili seconds or
micro seconds. The APIs that take time as a parameter are not
impacted and they continue to pass time in mili seconds.
2. Timers would not be programmed in periodic mode
generating ticks. Instead they would be programmed in one
shot mode to generate events at the time the kernel scheduler
needs to gain control for its scheduling activities like
timers, timeouts, time slicing, idling etc.
3. The scheduler provides interfaces that the timer drivers
use to announce elapsed time and get the next time the scheduler
needs a timer event. It is possible that the scheduler may not
need another timer event, in which case the system would wait
for a non-timer event to wake it up if it is idling.
4. New APIs are defined to be implemented by timer drivers. Also
they need to handler timer events differently. These changes
have been done in the HPET timer driver. In future other timers
that support tickles kernel should implement these APIs as well.
These APIs are to re-program the timer, update and announce
elapsed time.
5. Philosopher and timer_api applications have been enabled to
test tickless kernel. Separate configuration files are created
which define the necessary CONFIG flags. Run these apps using
following command
make pristine && make BOARD=qemu_x86 CONF_FILE=prj_tickless.conf qemu
Jira: ZEP-339 ZEP-1946 ZEP-948
Change-Id: I7d950c31bf1ff929a9066fad42c2f0559a2e5983
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
Future tickless kernel patches would be inserting some
code before call to Swap. To enable this it will create
a mcro named as the current _Swap which would call first
the tickless kernel code and then call the real __swap()
Jira: ZEP-339
Change-Id: Id778bfcee4f88982c958fcf22d7f04deb4bd572f
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
Historically, space for struct k_thread was always carved out of the
thread's stack region. However, we want more control on where this data
will reside; in memory protection scenarios the stack may only be used
for actual stack data and nothing else.
On some platforms (particularly ARM), including kernel_arch_data.h from
the toplevel kernel.h exposes intractable circular dependency issues.
We create a new per-arch header "kernel_arch_thread.h" with very limited
scope; it only defines the three data structures necessary to instantiate
the arch-specific bits of a struct k_thread.
Change-Id: I3a55b4ed4270512e58cf671f327bb033ad7f4a4f
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
There are a few places that we used an naked unsigned type, lets be
explicit and make it 'unsigned int'.
Change-Id: I33fcbdec4a6a1c0b1a2defb9a5844d282d02d80e
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Replace the existing Apache 2.0 boilerplate header with an SPDX tag
throughout the zephyr code tree. This patch was generated via a
script run over the master branch.
Also updated doc/porting/application.rst that had a dependency on
line numbers in a literal include.
Manually updated subsys/logging/sys_log.c that had a malformed
header in the original file. Also cleanup several cases that already
had a SPDX tag and we either got a duplicate or missed updating.
Jira: ZEP-1457
Change-Id: I6131a1d4ee0e58f5b938300c2d2fc77d2e69572c
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Also remove mentions of unified kernel in various places in the kernel,
samples and documentation.
Change-Id: Ice43bc73badbe7e14bae40fd6f2a302f6528a77d
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
