Commit Graph

85 Commits

Author SHA1 Message Date
Andy Ross 22642cf309 kernel: Clean up _unpend_thread() API
Almost everywhere this was called, it was immediately followed by
_abort_thread_timeout(), for obvious reasons.  The only exceptions
were in timeout and k_timer expiration (unifying these two would be
another good cleanup), which are peripheral parts of the scheduler and
can plausibly use a more "internal" API.

So make the common case the default, and expose the old behavior as
_unpend_thread_no_timeout().  (Along with identical changes for
_unpend_first_thread) Saves code bytes and simplifies scheduler
surface area for future synchronization work.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-04-24 03:57:20 +05:30
Andy Ross 15cb5d7293 kernel: Further unify _reschedule APIs
Now that other work has eliminated the two cases where we had to do a
reschedule "but yield even if we are cooperative", we can squash both
down to a single _reschedule() function which does almost exactly what
legacy _Swap() did, but wrapped as a proper scheduler API.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-04-24 03:57:20 +05:30
Andy Ross 8606fabf74 kernel: Scheduler refactoring: use _reschedule_*() always
There was a somewhat promiscuous pattern in the kernel where IPC
mechanisms would do something that might effect the current thread
choice, then check _must_switch_threads() (or occasionally
__must_switch_threads -- don't ask, the distinction is being replaced
by real English words), sometimes _is_in_isr() (but not always, even
in contexts where that looks like it would be a mistake), and then
call _Swap() if everything is OK, otherwise releasing the irq_lock().
Sometimes this was done directly, sometimes via the inverted test,
sometimes (poll, heh) by doing the test when the thread state was
modified and then needlessly passing the result up the call stack to
the point of the _Swap().

And some places were just calling _reschedule_threads(), which did all
this already.

Unify all this madness.  The old _reschedule_threads() function has
split into two variants: _reschedule_yield() and
_reschedule_noyield().  The latter is the "normal" one that respects
the cooperative priority of the current thread (i.e. it won't switch
out even if there is a higher priority thread ready -- the current
thread has to pend itself first), the former is used in the handful of
places where code was doing a swap unconditionally, just to preserve
precise behavior across the refactor.  I'm not at all convinced it
should exist...

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-04-24 03:57:20 +05:30
Leandro Pereira 541c3cb18b kernel: sched: Fix validation of priority levels
A priority value cannot be simultaneously higher than the maximum
possible value and smaller than the minimum value.  Rewrite the
_VALID_PRIO() macro as a function so that this if either of these
invariants are invalid, the priority is considered invalid.

Coverity-CID: 182584
Coverity-CID: 182585
Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
2018-04-21 08:39:42 -07:00
Kumar Gala 79d151f81d kernel: Fix building of k_thread_create
commit ec7ecf7900 moved some code around
such that the total_size variable is used regardless of how
CONFIG_MPU_REQUIRES_POWER_OF_TWO_ALIGNMENT is set.  So move the
decleration of total_size outside of the ifndef block so things build
properly.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2018-04-10 22:26:01 -04:00
Andrew Boie ec7ecf7900 kernel: restore stack size check
The handler for k_thread_create() wasn't verifying that the
provided stack size actually fits in the requested stack object
on systems that enforce power-of-two size/alignment for stacks.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2018-04-10 10:58:12 -04:00
Leandro Pereira 1ccd715577 kernel: thread: Consider stack pointer fuzz underflow
When randomizing the stack pointer on thread creation
(CONFIG_STACK_POINTER_RANDOM), the fuzz amount might exceed the stack
size, causing an underflow.

Ensure that this will never underflow by only adjusting the stack size
if there's enough space.

Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
2018-04-03 12:32:56 -07:00
Andy Ross 85bc0a3fe6 kernel: Cleanup, unify _add_thread_to_ready_q() and _ready_thread()
The scheduler exposed two APIs to do the same thing:
_add_thread_to_ready_q() was a low level primitive that in most cases
was wrapped by _ready_thread(), which also (1) checks that the thread
_is_ready() or exits, (2) flags the thread as "started" to handle the
case of a thread running for the first time out of a waitq timeout,
and (3) signals a logger event.

As it turns out, all existing usage was already checking case #1.
Case #2 can be better handled in the timeout resume path instead of on
every call.  And case #3 was probably wrong to have been skipping
anyway (there were paths that could make a thread runnable without
logging).

Now _add_thread_to_ready_q() is an internal scheduler API, as it
probably always should have been.

This also moves some asserts from the inline _ready_thread() wrapper
to the underlying true function for code size reasons, otherwise the
extra use of the inline added by this patch blows past code size
limits on Quark D2000.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-03-18 16:58:12 -04:00
Andrew Boie 83752c1cfe kernel: introduce initial stack randomization
This is a component of address space layout randomization that we can
implement even though we have a physical address space.

Support for upward-growing stacks omitted for now, it's not done
currently on any of our current or planned architectures.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2018-03-16 16:25:22 -07:00
Andy Ross 245b54ed56 kernel/include: Missed nano_internal.h -> kernel_internal.h spots
Update heading naming given recent rename

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Andy Ross 9c62cc677d kernel: Add kswap.h header to unbreak cycles
The xtensa-asm2 work included a patch that added nano_internal.h
includes in lots of places that needed to have _Swap defined, because
it had to break a cycle and this no longer got pulled in from the arch
headers.

Unfortunately those new includes created new and more amusing cycles
elsewhere which led to breakage on other platforms.

Break out the _Swap definition (only) into a separate header and use
that instead.  Cleaner.  Seems not to have any more hidden gotchas.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Andy Ross 32a444c54e kernel: Fix nano_internal.h inclusion
_Swap() is defined in nano_internal.h.  Everything calls _Swap().
Pretty much nothing that called _Swap() included nano_internal.h,
expecting it to be picked up automatically through other headers (as
it happened, from the kernel arch-specific include file).  A new
_Swap() is going to need some other symbols in the inline definition,
so I needed to break that cycle.  Now nothing sees _Swap() defined
anymore.  Put nano_internal.h everywhere it's needed.

Our kernel includes remain a big awful yucky mess.  This makes things
more correct but no less ugly.  Needs cleanup.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Ramakrishna Pallala 3f2f1223ac kernel: thread: Remove unused _k_thread_single_start()
Remove unused _k_thread_single_start() as this logic is
now moved to _impl_k_thread_start().

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
2018-02-13 17:26:21 -05:00
Andy Gross 1c047c9bef arm: userspace: Add ARM userspace infrastructure
This patch adds support for userspace on ARM architectures.  Arch
specific calls for transitioning threads to user mode, system calls,
and associated handlers.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-02-13 12:42:37 -08:00
Adithya Baglody 10db82bfed kernel: thread: Repeated thread abort crashes.
When CONFIG_THREAD_MONITOR is enabled, repeated thread abort
calls on a dead thread will cause the _thread_monitor_exit to
crash.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-01-24 18:18:53 +05:30
Anas Nashif 94d034dd5e kernel: support custom k_busy_wait()
Support architectures implementing their own k_busy_wait.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-27 14:16:08 -05:00
Anas Nashif fb4eecaf5f kernel: threads: remove thread groups
We have removed this features when we moved to the unified kernel. Those
functions existed to support migration from the old kernel and can go
now.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-09 08:48:51 -06:00
Andrew Boie a7fedb7073 _setup_new_thread: fix crash on ARM
On arches which have custom logic to do the initial swap into
the main thread, _current may be NULL. This happens when
instantiating the idle and main threads.

If this is the case, skip checks for memory domain and object
permission inheritance, in this case there is never anything to
inherit.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-13 16:25:40 -08:00
Andrew Boie 0bf9d33602 mem_domain: inherit from parent thread
New threads inherit any memory domain membership held by the
parent thread.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-08 09:14:52 -08:00
Andrew Boie 818a96d3af userspace: assign thread IDs at build time
Kernel object metadata had an extra data field added recently to
store bounds for stack objects. Use this data field to assign
IDs to thread objects at build time. This has numerous advantages:

* Threads can be granted permissions on kernel objects before the
  thread is initialized. Previously, it was necessary to call
  k_thread_create() with a K_FOREVER delay, assign permissions, then
  start the thread. Permissions are still completely cleared when
  a thread exits.

* No need for runtime logic to manage thread IDs

* Build error if CONFIG_MAX_THREAD_BYTES is set too low

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-03 11:29:23 -07:00
Ramakrishna Pallala 1777c57bec kernel: fix bit clearing logic in _k_thread_group_leave
Fix init_group bit clearing in _k_thread_group_leave()

Fix _k_object_uninit calling order. Though the order won't
make much difference in this case it is always good to destroy
or uninitialize in the reverse order of the object creation or
initialization.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
2017-10-27 10:56:58 -07:00
Andrew Boie e12857aabf kernel: add k_thread_access_grant()
This is a runtime counterpart to K_THREAD_ACCESS_GRANT().
This function takes a thread and a NULL-terminated list of kernel
objects and runs k_object_access_grant() on each of them.
This function doesn't require any special permissions and doesn't
need to become a system call.

__attribute__((sentinel)) added to warn users if they omit the
required NULL termination.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-10-18 07:37:38 -07:00
Andrew Boie 877f82e847 userspace: add K_THREAD_ACCCESS_GRANT()
It's possible to declare static threads that start up as K_USER,
but these threads can't do much since they start with permissions on
no kernel objects other than their own thread object.

Rather than do some run-time synchronization to have some other thread
grant the necessary permissions, we introduce macros
to conveniently assign object permissions to these threads when they
are brought up at boot by the kernel. The tables generated here
are constant and live in ROM when possible.

Example usage:

K_THREAD_DEFINE(my_thread, STACK_SIZE, my_thread_entry,
                NULL, NULL, NULL, 0, K_USER, K_NO_WAIT);

K_THREAD_ACCESS_GRANT(my_thread, &my_sem, &my_mutex, &my_pipe);

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-10-18 07:37:38 -07:00
Andrew Boie c5c104f91e kernel: fix k_thread_stack_t definition
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>
2017-10-17 08:24:29 -07:00
Andrew Boie 662c345cb6 kernel: implement k_thread_create() as a syscall
User threads can only create other nonessential user threads
of equal or lower priority and must have access to the entire
stack area.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-10-16 19:02:00 -07:00