Commit Graph

1685 Commits

Author SHA1 Message Date
Sathish Kuttan a8aa235d9b kernel: msg_q: k_msgq_peek() implementation
Add implementation for k_msgq_peek() which is similar to k_msgq_get()
except the message is not deleted from the queue.

Signed-off-by: Sathish Kuttan <sathish.k.kuttan@intel.com>
2018-11-19 17:53:22 -05:00
Andrew Boie 42cfd4ff26 kernel: expose k_busy_wait() to user mode
If we just had the kernel's implementation, we could
just move this to lib/, but possible arch-specific
implementations dictate that we just make this a
syscall.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2018-11-15 16:20:36 -05:00
Andrew Boie f253d0779d k_mem_slab: track as a kernel object
We aren't going to allow any user mode access to the
k_mem_slab APIs, but in some cases (specifically in the
case of the I2S subsystem) we need to allow user mode
to assign a memory slab to a particular driver.

This will let us verfiy (in supervisor mode) that a provided
k_mem_slab pointer is really a k_mem_slab, and know its
initialization state, and have permissions assigned to it.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2018-11-15 16:20:36 -05:00
Ioannis Glaropoulos d8b51ea9cd kernel: mem_domain: optimize sane partition checking
This commit optimizes the process of checking that the
added partitions in a mem_domain are sane. It places the
sane_partition checking inside the loop of adding the
partitions in the mem_domain, so that the checkings are
not performed twice, and no partition is checked against
itself.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-11-15 08:18:59 -05:00
Ioannis Glaropoulos 3e390ed42d kernel: mem_domain: fix partition end address calculations
This commit fixes the calculations of the partition ending
addresses in two places in the code, according to:
<last> = <start> + <size> - 1. We also rename 'end' to 'last'
to stress that we calculate the last address in the partition.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-11-15 08:18:59 -05:00
Andrew Boie 9d14874db1 kernel: expose device_get_binding() to user mode
User mode may need to use this API to get a handle on
devices by name, expose as a system call. We impose
a maximum name length as the system call handler needs
to make a copy of the string passed in from user mode.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2018-11-13 19:06:05 -05:00
Andy Ross 1c3051459b kernel/sched: Fix race in k_sched_time_slice_set()
If this function is itself interrupted by a timeslice event, the
slicing state can be corrupted.  Just re-use the scheduler lock
instead of using a new spinlock; this is a low-latency function that
won't deadlock.  Found by inspection.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-11-13 17:10:07 -05:00
Andy Ross c0a184c067 drivers/timer: Select tickless via driver kconfig flag
Add a TICKLESS_CAPABLE kconfig variable which is used by the kernel to
select tickless mode's default automatically on drivers that support
it (rather than having to set the default per-board).  Select it from
the ARM SysTick and Intel HPET drivers.

Also remove the old qemu_cortex_m3 default settings which this
replaces.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-11-13 17:10:07 -05:00
Flavio Ceolin 22236c9d6d kernel: Make tag identifiers unique
Some places are using the same tag identifier with different types.
This is a MISRA-C violation and makes the code less readable.

MISRA-C rule 5.7

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-11-06 16:20:15 -05:00
Flavio Ceolin aecd4ecb8d kernel: Change k_poll_signal api
k_poll_signal was being used by both, struct and function. Besides
this being extremely error prone it is also a MISRA-C violation.
Changing the function to contain a verb, since it performs an action
and the struct will be a noun. This pattern must be formalized and
followed and across the project.

MISRA-C rules 5.7 and 5.9

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-11-04 11:37:24 -05:00
Flavio Ceolin dfbe03249d kernel: stack: Making if's body a compound statement
MISRA-C rule 15.6

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-11-04 11:37:24 -05:00
Flavio Ceolin a406b88fca kernel: Remove duplicated identifier
There was an struct and a variable called _kernel. This is error prone
and a MISRA-C violation. It is changing the struct to have a unique
identifier.

MISRA-C rule 5.8

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-11-04 11:37:24 -05:00
Flavio Ceolin ac14685211 kernel: Delimiting the scope of some variables
According with MISRA-C an object should be defined in a block scope if
it is used in a single function.

MISRA-C rule 8.9

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-11-04 11:37:24 -05:00
Flavio Ceolin 4369363f6c kernel: mutex: Change variable declaration
This is not violating any MISRA-C rule, though, it seems to be
triggering a false (rule 9.1) positive in some static analysis
tools. Nevertheless, it is more readable declare all variables in the
same scope together.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-11-04 11:37:24 -05:00
Flavio Ceolin a3dddedab6 kernel: Use distinct macro names
There is a struct and a macro called _ready_q, this is error
prone. Just removing it.

MISRA-C rule 5.4

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-10-31 19:43:47 -04:00
Adithya Baglody 87e592ebda kernel: mutex.c: MISRA C compliance.
This patch fixes few MISRA issues present in mutex.c.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-31 08:44:47 -04:00
Adithya Baglody fac6885e55 kernel: alert: Declare tracing variables only when needed.
The tracing variable in alert.c was declared by default. This
should have been declared only when CONFIG_OBJECT_TRACING is set.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-31 08:44:47 -04:00
Adithya Baglody 2a78b8d86f kernel: queue: MISRA C compliance.
This patch fixes few issues in queue.c. This patch also changes
the return type of k_queue_alloc_append and k_queue_alloc_prepend
from int to s32_t.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-31 08:44:47 -04:00
Adithya Baglody 8feda92abc kernel: device: MISRA C compliance.
This patch fixes few issues in device.c.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-31 08:44:47 -04:00
Piotr Zięcik 7700eb2a15 kernel: sched: Make k_sleep() similar to POSIX equivalent
This commit introduces k_sleep() return value, which provides
information about actual sleep time. If the returned value is
not-zero, the thread slept shorter than requested, which is
only possible if the thread has been woken up by k_wakeup() call.

Signed-off-by: Piotr Zięcik <piotr.ziecik@nordicsemi.no>
2018-10-30 18:27:31 +01:00
Marek Pieta e87193896a subsys: debug: tracing: Fix thread tracing
Change fixes issue with thread execution tracing.

Signed-off-by: Marek Pieta <Marek.Pieta@nordicsemi.no>
2018-10-29 22:09:12 -04:00
Ioannis Glaropoulos 3e02f38a38 kernel: mem_domain: minor typo fixes
Fixing a few minor typo fixes in kernel/mem_domain.c
and the respective documentation section.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-10-29 12:34:12 -04:00
Kumar Gala 0776392e4c kernel: msq_q: Fix compile warning
Fix a compile warning if we build using int types defined to match the
compiler.  We get the following warnings:

kernel/msg_q.c: In function ‘_impl_k_msgq_alloc_init’:
kernel/msg_q.c:75:9: warning: passing argument 3 of ‘__builtin_umul_overflow’ from incompatible pointer type [-Wincompatible-pointer-types]
         (u32_t *)&total_size)) {
         ^
kernel/msg_q.c:75:9: note: expected ‘unsigned int *’ but argument is of type ‘u32_t * {aka long unsigned int *}’

__builtin_umul_overflow expects to be passed unsigned int for all its
arguments, so cast to that instead of u32_t.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2018-10-29 10:52:00 -04:00
Spoorthi K b6cd192fa5 kernel: sched: Fix compiler warning
Ignore return value of _Swap() as it is not
used anywhere.

Signed-off-by: Spoorthi K <spoorthi.k@intel.com>
2018-10-24 09:48:17 +01:00
Paul Sokolovsky d91c11f5bf kernel: system_work_q: Set dedicated "sysworkq" name.
Previously, a generic "workqueue" name was used, but there're few
workqueues in a typical Zephyr setup, and it wasn't possible to
distinguish them.

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
2018-10-19 07:58:45 -04:00
Adithya Baglody 4b066212b6 kernel: sem: Fix few MISRA C violations.
This patch fixes few of the violations inside sem.c

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-17 12:17:58 -04:00
Adithya Baglody 6176692f4b kernel: ksched.h: Incorrect argument type in _pend_current_thread
In _pend_current_thread the argument key is always a unsigned
interger type and this function forces it to become a signed
interger. This is a dangerous behavior and cant be trusted to
work as expected.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-17 12:17:58 -04:00
Andy Ross 386894c2fb kernel/timeout: Fix build breakage due to stdio name collision
Duh: "remove()" is a POSIX symbol, and on at least some platforms
stdio.h can be included here out of platform headers causing a name
collision.

Fixes #10669's direct issue, though the broader issue of how to choose
names for statics remains controversial.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-17 12:15:44 -04:00
Paul Sokolovsky b779ea2d19 kernel: syscall_handler.h: Typo fix in docstring
Should be "fails" instead of "files".

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
2018-10-17 10:32:10 -04:00
Adithya Baglody 28080d3896 kernel: MISRA C: Fixes a few MISRA C issues.
MISRA C guideline compliance for various rules.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-17 07:59:51 -04:00
Adithya Baglody 1424561252 kernel: sched: Fixed incorrect argument type of _reschedule()
This API shouldn't take a int type but instead it should take
u32_t. This argument has to be similar to irq_lock() and
irq_unlock().

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-10-17 07:59:51 -04:00
Andy Ross 7a035c0dc7 kernel/sched: Fix timeslice accounting for already-elapsed ticks
In tickless mode, not all elapsed ticks may have been announced yet,
so future z_time_slice() calls will include "extra" ticks that we have
to account for when setting up the slice count.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 7617371ecc kernel/timeout: Clamp ticks argument to lower bound
Our funny convention holds that passing ticks==1 to _add_timeout()
means "at the next tick".  But that means that 1, 0, and all negative
numbers are expected to behave the same.  In ticked mode, that's fine
because it will, after all, expire at the next tick.

But in tickless, the next announcement may be for several ticks, and
that zero will appear to expire "before" the next tick in the
consumption loop.

Make sure all "next tick" expirations look the same.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 9ce9677888 kernel/timeout: Fix elapsed logic
When fetching the next timeout to expire, the value is relative to the
last announced tick, so you subtract the timer-provided elapsed time
to get the true delta from "now".  When adding a new timeout, you
*have* a value relative to now, so you compute the delta vs. the last
announced tick by adding the elapsed() time.  Duh.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 1cfff07480 kernel/timeout: Fix announcement tick logic
This was wrong in subtle ways.  In tickless mode it's possible to get
an announcement for multiple ticks at a time and have multiple
callbacks to execute that were technically scheduled at different
times.  We want to fix the current tick at the value represented by
the currently-executing callback's EXPIRATION (even if we missed it!),
so that any new timeouts it sets (c.f. a k_timer period) happen at the
right point, in phase with the expected series.  In single-tick mode
the code ends up the same always, so the bug wasn't visible.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross d8421adadd kernel/timeout: Fix synchronization in z_tick_get_32()
The previous comment correctly and carefully explained why the 64 bit
value in curr_tick doesn't require locking when reading only the low
32 bits.

It completely missed the fact that the calculation of elapsed time and
the read of curr_tick ABSOLUTELY DO require locking, because the
former is expressed in terms of the latter.  This was always bug, even
in the old code, but never witnessed because we ran so little software
in tickless mode.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 1129ea9394 kernel/sched: Fix timeslicing predicate
It's possible to interrupt a thread that has already scheduled a
timeout.  Really this is a race against the usage of
_add_thread_timeout() and needs some design work to provide proper
locking (which is a distinct requirement from the scheduler lock and
timeout lock!), as the users of that API are spread around the kernel.
But existing usage always schedules the timeouts first, so this is
safe.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 2dd9e2cad4 kernel/sched: Remove spurious locking
The timeout APIs are properly synchronized now.  This irq_lock() (and
the comment explaining it) isn't needed anymore.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 08397277fc kernel/kconfig: Move TICKLESS options out of power management tree
These options are rapidly becoming a default configuration, which is
complicated by having them be hidden inside of a SYS_POWER_MANAGEMENT
variable that has to be enabled first.  Put them at the top level of
the kernel config.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross cfe62038d2 kernel: Checkpatch fixups
I was pretty careful, but these snuck in.  Most of them are due to
overbroad string replacements in comments.  The pull request is very
large, and I'm too lazy to find exactly where to back-merge all of
these.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 987c0e5fc1 kernel: New timeout implementation
Now that the API has been fixed up, replace the existing timeout queue
with a much smaller version.  The basic algorithm is unchanged:
timeouts are stored in a sorted dlist with each node nolding a delta
time from the previous node in the list; the announce call just walks
this list pulling off the heads as needed.  Advantages:

* Properly spinlocked and SMP-aware.  The earlier timer implementation
  relied on only CPU 0 doing timeout work, and on an irq_lock() being
  taken before entry (something that was violated in a few spots).
  Now any CPU can wake up for an event (or all of them) and everything
  works correctly.

* The *_thread_timeout() API is now expressible as a clean wrapping
  (just one liners) around the lower-level interface based on function
  pointer callbacks.  As a result the timeout objects no longer need
  to store backpointers to the thread and wait_q and have shrunk by
  33%.

* MUCH smaller, to the tune of hundreds of lines of code removed.

* Future proof, in that all operations on the queue are now fronted by
  just two entry points (_add_timeout() and z_clock_announce()) which
  can easily be augmented with fancier data structures.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 52e444bc05 kernel: Move timeout_remaining API
_timeout_remaining_get() was a function on a struct _timeout, doing
iteration on the timeout list, but it was defined in timer.c (the
higher level abstraction).

Move it to where it belongs.  Also have it return ticks instead of ms
to conform to scheme in the rest of the timeout API.  And rename it to
a more standard zephyr name.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 96013b0375 system_timer.h: Change "now" uptime API to be simpler for drivers
The current z_clock_uptime() call (recently renamed from
_get_elapsed_program_time) requires the driver to track a full 64 bit
uptime value in ticks, which is entirely separate from the one the
kernel is already keeping.

Don't do that.  Just ask the drivers to track uptime since the last
call to z_clock_announce(), since that is going to map better to
built-in hardware capability.

Obviously existing drivers already have this feature, so they're
actually getting slightly larger in order to implement the new API in
terms of the old one.  But future drivers will thank us.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross fe82f1c2af kernel/timeout: Refactor API
Add the callback parameter to add_timeout(), and remove the thread
argument.  Now the "low level" timeout API can be expressed without
reference to threads.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 5d203523b6 kernel/timeout: Eliminate wait_q parameters from API
Now that this is known to be an unused value, remove it from the API.
Note that this caught a few spots where we were passing values (a
non-NULL wait_q with a NULL thread handle) that were always being
ignored before.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross d61b1f8ef8 kernel/timeout: Remove timeout wait_q field
Per previous patch, this is known to be identical with
thread->pended_on.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 15d520819d kernel/timeout: Prepare unification of timeout/thread wait_q fields
The existing timeout API wants to store a wait_q on which the thread
is waiting, but it only uses that value in one spot (and there only as
a boolean flag indicating "this thread is waiting on a wait_q).

As it happens threads can already store their own backpointers to a
wait_q (needed for the SCALABLE scheduler backend), so we should use
that instead.

This patch doesn't actually perform that unification yet.  It
reorgnizes things such that the pended_on field is always set at the
point of timeout interaction, and adds a bunch of asserts to make 100%
sure the logic is correct.  The next patch will modify the API.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 2ae8f50936 kernel/include: Move stubs for timeout functions to their declarations
The timeout_q.h scheme, where it declared real functions, but the
stubs for when there was no clock were in wait_q.h was senselessly
weird.  Put them in the same file.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 9098a45c84 kernel: New timeslicing implementation
Instead of checking every time we hit the low-level context switch
path to see if the new thread has a "partner" with which it needs to
share time, just run the slice timer always and reset it from the
scheduler at the points where it has already decided a switch needs to
happen.  In TICKLESS_KERNEL situations, we pay the cost of extra timer
interrupts at ~10Hz or whatever, which is low (note also that this
kind of regular wakeup architecture is required on SMP anyway so the
scheduler can "notice" threads scheduled by other CPUs).  Advantages:

1. Much simpler logic.  Significantly smaller code.  No variance or
   dependence on tickless modes or timer driver (beyond setting a
   simple timeout).

2. No arch-specific assembly integration with _Swap() needed

3. Better performance on many workloads, as the accounting now happens
   at most once per timer interrupt (~5 Hz) and true rescheduling and
   not on every unrelated context switch and interrupt return.

4. It's SMP-safe.  The previous scheme kept the slice ticks as a
   global variable, which was an unnoticed bug.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 8b54953e4b kernel/sys_clock: Fix build when !SYS_CLOCK_EXISTS
This got broken.  Add some #ifery to handle the case.  Not clean, will
clean up in a future pass once the API is final.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 25863549be kernel: Remove clock_always_on control from k_busy_wait()
This feature was a useless noop based on mistaken API understanding.

The idea seems to have been that k_busy_wait() included guards to
ensure "clock_always_on" was true duing the loop, presumably because
the original author was afraid that "turning the clock off" would
affect the operation of k_cycle_get_32().

Then later someone came around and "optimized" this for Quark SE,
where the cycle counter is the RTC and unrelated to the timer driver
used by the clock_always_on feature.  (Except even there it presumably
should have been done at the SoC level and not just in the C1000
devboard -- note that Arduino 101 never would have gotten this).

But it was all a mistake: "clock_always_on" has nothing to do with
en/disabling the system cycle timer (which never happens when the
system is active, that's a feature of idle), it's a control over the
delivery of timer interrupts.  And needless to say we don't care about
timer interrupts when we're spinning on a cycle counter.

Yank the whole mess.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 1b3149cea1 kernel/sys_clock.c: Add asserts to watch dueling "set time" APIs
The current API has an rather unfortuate collision between two APIs:
z_clock_announce(), which is called out of the timer interrupt to
inform the kernel of time passage (and which is responsible for
invoking timer callbacks), and z_tick_set(), which is ALSO used by the
timer drivers for... confusing and inconsistent purposes.

This is sort of a mess.  The tick_set API needs to go away, but before
that I'm adding some assertions to at least make sure the existing
drivers are using them consistently.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 1c08aefe56 kernel/timeoutq: Uninline the timeout methods
There was no good reason to have these rather large functions in a
header.  Put them into sys_clock.c for now, pending rework to the
system.

Now the API is clearly visible in a small header.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 7aae75bd1c idle: Fix tickless timeout behavior
If the idle code was detecting that it needed to sleep for less than
CONFIG_SYS_TICKLESS_IDLE_THRESH, then it would never call
z_clock_set_timeout() at all, which means that the system would never
wake up unless it already had a timeout scheduled!  Apparently we
lacked a test case to detect this condition.

Honestly this seems like a crazy feature to me.  There's no benefit in
delivering needless tick announcements.  If the system has the
capacity to enter deeper sleep for long timeouts, that's already
exposed via the PM APIs, the timer subsystem needn't be involved.
But... we actually have a test (tickless_concept) that looks at this,
so support it for now and consider deprecation later.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross d7b35c9bd6 idle: Remove needless "expired" logic in sys_power_save_idle()
This code (just refactored as part of the timer API work) turns out to
be needless.  It's trying to detect the case where we're being asked
to idle for zero time, but that's not possible with a properly
functioning timer driver: the call to z_clock_announce() must happen
out of an interrupt, and this is the idle thread, which must sit below
any possible interrupt priority.  The call to z_clock_uptime() must
not ever return "too late" until after the timer interrupt has fired,
at which point we'll be inspecting the next timeout (which itself is
guaranteed to be in the future for the same reason).

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 722a888ef7 timer: Clean up hairy tickless APIs
The tickless driver had a bunch of "hairy" APIs which forced the timer
drivers to do needless low-level accounting for the benefit of the
kernel, all of which then proceeded to implement them via cut and
paste.  Specifically the "program_time" calls forced the driver to
expose to the kernel exactly when the next interrupt was due and how
much time had elapsed, in a parallel API to the existing "what time is
it" and "announce a tick" interrupts that carry the same information.

Remove these from the kernel, replacing them with synthesized logic
written in terms of the simpler APIs.

In some cases there will be a performance impact due to the use of the
64 bit uptime call, but that will go away soon.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 1a1a9539ea include/system_timer.h: Timer API cleanup
Rename timer driver API functions to be consistent.  ADD DOCS TO THE
HEADER so implementations understand what the requirements are.
Remove some unused functions that don't need declarations here.

Also removes the per-platform #if's around the power control callback
in favor of a weak-linked noop function in the driver initialization
(adds a few bytes of code to default platforms -- we'll live, I
think).

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross ab488277bc drivers/timer: Unify timeout setting APIs
The existing API had two almost identical functions: _set_time() and
_timer_idle_enter().  Both simply instruct the timer driver to set the
next timer interrupt expiration appropriately so that the call to
z_clock_announce() will be made at the requested number of ticks.  On
most/all hardware, these should be implementable identically.

Unfortunately because they are specified differently, existing drivers
have implemented them in parallel.

Specify a new, unified, z_clock_set_timeout().  Document it clearly
for implementors.  And provide a shim layer for legacy drivers that
will continue to use the old functions.

Note that this patch fixes an existing bug found by inspection: the
old call to _set_time() out of z_clock_announce() failed to test for
the "wait forever" case in the situation where clock_always_on is
true, meaning that a system that reached this point and then never set
another timeout would freeze its uptime clock incorrectly.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross fa99ad66d0 sys_clock: Fix up tick announce API
There were three separate "announce ticks" entry points exposed for
use by drivers.  Unify them to just a single z_clock_announce()
function, making the "final" tick announcement the business of the
driver only, not the kernel.

Note the oddness with "_sys_idle_elapsed_ticks": this was a global
variable exposed by the kernel.  But it was never actually used by the
kernel.  It was updated and inspected only within the timer drivers,
and only so that it could be passed back to the kernel as the default
(actually hidden) argument to the announce function.  Break this false
dependency by putting this variable into each timer driver
individually.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 317178b88f sys_clock: Fix unsafe tick count usage
The system tick count is a 64 bit quantity that gets updated from
interrupt context, meaning that it's dangerously non-atomic and has to
be locked.  The core kernel clock code did this right.

But the value was also exposed to the rest of the universe as a global
variable, and virtually nothing else was doing this correctly.  Even
in the timer ISRs themselves, the interrupts may be themselves
preempted (most of our architectures support nested interrupts) by
code that wants to set timeouts and inspect system uptime.

Define a z_tick_{get,set}() API, eliminate the old variable, and make
sure everyone uses the right mechanism.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross b8ffd9acd6 sys_clock: Make clock_always_on true by default
This flag is an indication to the timer driver that the OS doesn't
care about rollover conditions of the tick count while idling, so the
system doesn't need to wake up once per counter flip[1].  Obviously in
that circumstance values returned from k_uptime_get_32() are going to
be wrong, so the implementation had an assert to check for misuse.

But no one understood that from the docs, so the only place these APIs
were used in practice were as "guards" around code that needed to call
k_uptime_get_32(), even though that's 100% wrong per docs!

Clarify the docs.  Remove the incorrect guards.  Change the flag to
initialize to true so that uptime isn't broken-by-default in tickless
mode.  Also move the implemenations of the functions out of the
header, as there's no good reason for these to need to be inlined.

[1] Which can be significant.  A 100MHz ARM using the 24 bit SysTick
    counter rolls over at about 6 Hz, and if it had to come out of
    idle at that rate it would be a significant power issue that would
    swamp the gains from tickless.  Obviously systems with slow
    counters like nRF or 64 bit ones like RISC-V or x86's TSC aren't
    as affected.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross b2e4283555 sys_clock: Make sys_clock_hw_cycles_per_tick() a proper API
This was another "global variable" API.  Give it function syntax too.
Also add a warning, because on nRF devices (at least) the cycle clock
runs in kHz and is too slow to give a precise answer here.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 393ec71ec3 clock: Remove CONFIG_TICKLESS_KERNEL_TIME_UNIT_IN_MICRO_SECS
This was only used in a few places just to indirect the already
perfectly valid SYS_CLOCK_TICKS_PER_SEC value.  There's no reason for
these to ever have been kconfig units, and in fact the distinction
appears to have introduced a hidden/untested bug in the power
subsystem (the two variables were used interchangably, but they were
defined in reciprocal units!).

Just use "ticks" as our time unit pervasively, and clarify the docs to
explain that.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Andy Ross 220d4f8347 sys_clock.h: Make "global variable" APIs into proper functions
The existing API defined sys_clock_{hw_cycles,ticks}_per_sec as simple
"variables" to be shared, except that they were only real storage in
certain modes (the HPET driver, basically) and everywhere else they
were a build constant.

Properly, these should be an API defined by the timer driver (who
controls those rates) and consumed by the clock subsystem.  So give
them function syntax as a stepping stone to get there.

Note that this also removes the deprecated variable
_sys_clock_us_per_tick rather than give it the same treatment.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-10-16 15:03:10 -04:00
Anas Nashif c77c043071 kernel: remove deprecated k_thread_cancel
Remove deprecated function k_thread_cancel. We now use k_thread_abort.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2018-10-09 13:58:01 -04:00
Anas Nashif 0a0c8c831f kernel: move to new logger
Use the new logger framework for kernel.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2018-10-08 17:49:12 -04:00
Flavio Ceolin 18af4c6299 kernel: Fix overflow test problem introduced in 92ea2f9
The builtin function __builtin_umul_overflow returns a boolean and
should not checked as an integer.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-10-04 05:20:29 -07:00
Flavio Ceolin 061a2c5b63 kernel: mempool: Remove unnecessary condition check
Removing an unnecessary check in k_mem_pool_alloc. The condition is
already being checked in the if.

MISRA-C rule 14.3

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 07:58:19 +05:30
Flavio Ceolin 3e97acc7f2 kernel: Sanitize if else statement according with MISRA-C
A final else statement must be provided when an if statement is
followed by one or more else if.

MISRA-C rule 15.7

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 07:58:19 +05:30
Flavio Ceolin 0b14866437 kernel: sys_clock: Remove unnecessary if
When delta_ticks_from_prev is not 0, the variable ticks will necessarily
be lesser or equal 0, so the if checking that is no necessary.

MISRA-C rule 15.7

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 07:58:19 +05:30
Flavio Ceolin 6fc84feaf2 kernel: syscalls: Change handlers namespace
According C99 the first 31 characters of an identifier must be unique.
Shortening the namespace of the generated objects to achieve it.

C99 - 5.2.4.1
MISRA-C rule 5.1

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 07:58:19 +05:30
Mark Ruvald Pedersen d67096da05 portability: Avoid void* arithmetics which is a GNU extension
Under GNU C, sizeof(void) = 1. This commit merely makes it explicit u8.

Pointer arithmetics over void types is:
 * A GNU C extension
 * Not supported by Clang
 * Illegal across all ISO C standards

See also: https://gcc.gnu.org/onlinedocs/gcc/Pointer-Arith.html

Signed-off-by: Mark Ruvald Pedersen <mped@oticon.com>
2018-09-28 07:57:28 +05:30
Flavio Ceolin ea716bf023 kernel: Explicitly comparing pointer with NULL
MISRA-C rule: 14.4

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 06:28:41 +05:30
Flavio Ceolin 92ea2f9189 kernel: Calling Z_SYSCALL_VERIFY_MSG with boolean expressions
Explicitly making a boolean expression when calling
Z_SYSCALL_VERIFY_MSG macro.

MISRA-C rule: 14.4

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 06:28:41 +05:30
Flavio Ceolin 02ed85bd82 kernel: sched: Change boolean APIs to return bool
Change APIs that essentially return a boolean expression  - 0 for
false and 1 for true - to return a bool.

MISRA-C rule 14.4

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 06:28:41 +05:30
Flavio Ceolin d8837c6888 kernel: Using boolean expression on ASSERT macros
ASSERT macro expects a boolean expression, making it
explicit.

MISRA-C rule 14.4

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 06:28:41 +05:30
Flavio Ceolin 6fdc56d286 kernel: Using boolean types for boolean constants
Make boolean expressions use boolean types.

MISRA-C rule 14.4

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-28 06:28:41 +05:30
Anas Nashif 57554055d2 kernel: add a new API for setting thread names
Added k_thread_name_set() and enable thread name setting when declaring
static threads. This is enabled only when THREAD_MONITOR is used. System
threads get a name by default.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2018-09-27 08:58:55 +05:30
Ioannis Glaropoulos 57b7c3ded9 kernel: improve help text of INIT_STACKS option
This commit improves the help text of INIT_STACKS
Kconfig option, so it indicates that the stack
initialization applies also to the interrupt stack.

Fixes #7196.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-09-26 18:26:03 -05:00
Sebastian Bøe c0287695fb kconfig: Remove remnants of unimplemented BUILD_TIMESTAMP feature
The Kconfig option CONFIG_BUILD_TIMESTAMP became unused when
BUILD_VERSION was introduced, but it's option and parts of it's
implementation was not completely cleaned from the repository.

Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>
2018-09-26 22:18:29 +05:30
Paul Sokolovsky 2df1829c55 kernel: thread: Typo fixes in comment
Typo fixes in comment to k_thread_foreach().

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
2018-09-26 17:46:23 +05:30
Daniel Leung 7228a60173 kernel: Fix compilation errors when CONFIG_TIMESLICING=n
Add ifdef guard to the z_reset_timeslice() to fix compilation
errors when CONFIG_TIMESLICING is disabled.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2018-09-25 12:54:58 +05:30
Ioannis Glaropoulos 66192618a7 arch: arm: Minor style and typo fixes in inline comments
Several style and typo fixes in inline comments of arm kernel
files and thread.c.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-09-24 04:56:34 -07:00
Findlay Feng 3c834bdf27 kernel: Fix list-node add again corruption case in timeout handling
The node of the timeout temporary list cannot be continued
to index the next node after being added again.

Signed-off-by: Findlay Feng <i@fengch.me>
2018-09-21 13:29:09 -04:00
Anas Nashif 0a73ea04fa kernel: remove deprecate k_call_stacks_analyze
This API was deperecated and is not being used in the tree anymore, so
remove it.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2018-09-21 10:33:05 -04:00
Flavio Ceolin 8f488ff32e kernel: stack: Fix k_stack_pop api
_pend_current_thread can return any arbitrary value set by
_set_thred_return_value(), it happens that most cases set 0. This
function can not rely on this behavior otherwise it may return an
invalid value and/or not set data's value.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-18 13:57:39 -04:00
Flavio Ceolin c806ac3d36 kernel: Compare pointers with NULL in while statements
Make while statement using pointers explicitly check whether
the value is NULL or not.

The C standard does not say that the null pointer is the same
as the pointer to memory address 0 and because of this is a good
practice always compare with the macro NULL.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-18 13:57:15 -04:00
Flavio Ceolin b3d9202704 kernel: Using boolean constants instead of 0 or 1
MISRA C requires that every controlling expression of and if or while
statement have a boolean type.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-18 13:57:15 -04:00
Flavio Ceolin 4218d5f8f0 kernel: Make If statement have essentially Boolean type
Make if statement using pointers explicitly check whether the value is
NULL or not.

The C standard does not say that the null pointer is the same as the
pointer to memory address 0 and because of this is a good practice
always compare with the macro NULL.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-18 13:57:15 -04:00
Sebastian Bøe 878a0f050e ld: Put 'sizeof(struct device)' in the generated offsets header
Rename _DEVICE_STRUCT_SIZE to _DEVICE_STRUCT_SIZEOF. This causes it to
be picked by the script 'gen_offset_header.py' and inserted into the
header file 'include/generated/offsets.h'.

Renaming from x_SIZE to x_SIZEOF will align it's name with the other
symbols that denote a sctruct's size, like K_THREAD_SIZEOF.

Furthermore, it will allow the symbol to be accessed through a header
file define, instead of only as an extern symbol. This is more
flexible, and more aligned with the other symbols in offsets.

Finally, if we are able to move all of offsets.c symbols into the
offsets.h header file we be able to remove offsets.o from the link and
thereby simplify the linking process.

Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>
2018-09-18 16:23:40 +02:00
Flavio Ceolin a7fffa9e00 headers: Fix headers guards
Any word started with underscore followed by and uppercase letter or a
second underscore is a reserved word according with C99.

With have *many* violations on Zephyr's code, this commit is tackling
only the violations caused by headers guards. It also takes the
opportunity to normalize them using the filename in uppercase and
replacing dot with underscore. e.g file.h -> FILE_H

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-17 15:49:26 -04:00
Flavio Ceolin 0a4478434e kernel; Checking functions return
Checking the return of some scattered functions across kernel.
MISRA-C requires that all non-void functions have their return value
checked, though, in some cases there is nothing to do. Just
acknowledging it.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin 65b5280e8f kernel: Check k_thread_create return value
k_thread_create is used only in k_word_q_start that has no error
handling, so the return of that function is not used.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin 8f72f245bd kernel: Explicitly check _abort_thread_timemout
A lot of times this API is called during some cleanup even if the
timeout was not set to make the code simpler. In these cases it's not
necessary checking the return. Adding a cast to acknowledge it.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin 98c64b6d92 kernel: Change _reschedule signature
_reschedule return's value is not used anywhere, except erroneously by
pthread_barrier_wait.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin 4d5397bb0a kernel: Ignore _abort_timeout return
Ignoring the return of _abort_timeout when there is nothing to
do. Either because the condition to return something different from 0
was prior checked or because it was called during come cleanup.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin 1663ca8590 kernel: Ignore _pend_current_thread return in some cases
There are some cases that there is nothing to do with
_pend_current_thread() return (that is _Swap return value).

As MISRA-C requires that all non-void functions have their
return value checked, we are explicitly ignoring it when there is
nothing to do.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin da49f2e440 coccicnelle: Ignore return of memset
The return of memset is never checked. This patch explicitly ignore
the return to avoid MISRA-C violations.

The only directory excluded directory was ext/* since it contains
only imported code.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin 5884c7f54b kernel: Explicitly ignoring _Swap return
Ignoring _Swap return where there is no treatment or nothing to do.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00
Flavio Ceolin 8a9ba10c2c kernel: swap: Fix __swap signature
__swap function was returning -EAGAIN in some case, though its return
value was declared as unsigned int.

This commit changes this function to return int since it can return a
negative value and its return was already been propagate as int.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2018-09-14 16:55:37 -04:00