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#
# 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
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