Commit Graph

9 Commits

Author SHA1 Message Date
Maciek Borzecki
ed016fa9a0 kernel: make sure that _thread_entry() declaration matches with definition
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>
2017-05-18 12:41:56 -05:00
Andrew Boie
d26cf2dc33 kernel: add k_thread_create() API
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>
2017-05-11 20:24:22 -04:00
Ramesh Thomas
89ffd44dfb kernel: tickless: Add tickless kernel support
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>
2017-04-27 13:46:28 +00:00
Ramesh Thomas
62eea121b3 kernel: tickless: Rename _Swap to allow creation of macro
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>
2017-04-27 13:46:26 +00:00
Andrew Boie
73abd32a7d kernel: expose struct k_thread implementation
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>
2017-04-26 16:29:06 +00:00
Kumar Gala
5742a508a2 kernel: cleanup use of naked unsigned in _new_thread
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>
2017-04-21 20:34:41 +00:00
David B. Kinder
ac74d8b652 license: Replace Apache boilerplate with SPDX tag
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>
2017-01-19 03:50:58 +00:00
Anas Nashif
dc3d73bf58 kernel: fix all nanokernel usage in comments
Also include kernel.h instead of nanokernel.h

Change-Id: I65dc5e31b5409b809397296817e2d5e7adf28892
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2016-12-21 18:45:03 +00:00
Anas Nashif
d687a95611 kernel: move kernel code to kernel/ directly
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>
2016-12-19 14:59:35 -05:00