kernel: update SCHED_CPU_MASK Kconfig doc

Fix reference to APIs and reformat kconfig help message.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
This commit is contained in:
Anas Nashif 2019-12-18 18:10:09 -05:00
commit 8d2675010a

View file

@ -126,20 +126,19 @@ config SCHED_CPU_MASK
bool "Enable CPU mask affinity/pinning API" bool "Enable CPU mask affinity/pinning API"
depends on SCHED_DUMB depends on SCHED_DUMB
help help
When true, the app will have access to the When true, the application will have access to the
z_thread_*_cpu_mask() APIs which control per-CPU affinity k_thread_cpu_mask_*() APIs which control per-CPU affinity masks in
masks in SMP mode, allowing apps to pin threads to specific SMP mode, allowing applications to pin threads to specific CPUs or
CPUs or disallow threads from running on given CPUs. Note disallow threads from running on given CPUs. Note that as currently
that as currently implemented, this involves an inherent implemented, this involves an inherent O(N) scaling in the number of
O(N) scaling in the number of idle-but-runnable threads, and idle-but-runnable threads, and thus works only with the DUMB
thus works only with the DUMB scheduler (as SCALABLE and scheduler (as SCALABLE and MULTIQ would see no benefit).
MULTIQ would see no benefit).
Note that this setting does not technically depend on SMP Note that this setting does not technically depend on SMP and is
and is implemented without it for testing purposes, but for implemented without it for testing purposes, but for obvious reasons
obvious reasons makes sense as an application API only where makes sense as an application API only where there is more than one
there is more than one CPU. With one CPU, it's just a CPU. With one CPU, it's just a higher overhead version of
higher overhead version of k_thread_start/stop(). k_thread_start/stop().
config MAIN_STACK_SIZE config MAIN_STACK_SIZE
int "Size of stack for initialization and main thread" int "Size of stack for initialization and main thread"