incubator-nuttx/syscall/Kconfig

#
# For a description of the syntax of this configuration file,
# see misc/tools/kconfig-language.txt.
#

if NUTTX_KERNEL

comment "System call configuration"

config SYS_RESERVED
	int "Number of reserved system calls"
	default 0
	---help---
		Kernel system calls may share the same software trapping mechanism
		as other functions used by architecture port.  Those software traps
		must be reserved for use exclusively by the architecture.  These
		value specifies the number of reserved software traps used by the
		architecture; number of the kernel system calls will begin with this
		number.

config SYS_NNEST
	int "Number of nested system calls"
	default 2
	---help---
		This is architecture dependent.  Most architectures allocate
		resources to manage a fixed, maximum number of nested system calls.
		A nested system call occurs in the following scenario:  (1) A non-
		privileged user thread executes a system call, (2) part of the
		system call processing cause a call back into the user space code,
		and (3) the user space code performs another system call.

		In the current design, this can happen only under one condition:
		When the kernel calls back into user space in order to allocate user
		space memory.  So it is expected that the maximum nesting level will
		be only 2.

endif