| layout | title | parent |
|---|---|---|
post |
3.3 Kconfig |
Lesson 3: Threads |
Threads are always included in the system configuration, therefore no additional configs need to be set.
However optionally the following configuration options can be set:
| Kconfig | Description |
|---|---|
| CONFIG_MAIN_THREAD_PRIORITY | Priority of initialization/main thread |
| CONFIG_MAIN_STACK_SIZE | Size of stack for initialization and main thread |
| CONFIG_IDLE_STACK_SIZE | Size of stack for idle thread |
| CONFIG_THREAD_CUSTOM_DATA | This option allows each thread to store 32 bits of custom data, which can be accessed using the k_thread_custom_data_xxx() APIs. |
| CONFIG_NUM_COOP_PRIORITIES | Number of cooperative priorities configured in the system |
| CONFIG_NUM_PREEMPT_PRIORITIES | Number of preemptible priorities available in the system |
| CONFIG_TIMESLICING | This option enables time slicing between preemptible threads of equal priority. |
| CONFIG_TIMESLICE_SIZE | This option specifies the maximum amount of time a thread can execute before other threads of equal priority are given an opportunity to run. A time slice size of zero means "no limit" (i.e. an infinitely large time slice). |
| CONFIG_TIMESLICE_PRIORITY | This option specifies the thread priority level at which time slicing takes effect; threads having a higher priority than this ceiling are not subject to time slicing. |
| CONFIG_USERSPACE | When enabled, threads may be created or dropped down to user mode, which has significantly restricted permissions and must interact with the kernel via system calls. |