incubator-nuttx/mm/iob/Kconfig

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#
# For a description of the syntax of this configuration file,
# see the file kconfig-language.txt in the NuttX tools repository.
#
menu "Common I/O Buffer Support"
config MM_IOB
bool "Enable generic I/O buffer support"
default n
---help---
This setting will build the common I/O buffer (IOB) support
library.
if MM_IOB
config IOB_NBUFFERS
int "Number of pre-allocated I/O buffers"
default 24 if (NET_WRITE_BUFFERS && !NET_READAHEAD) || (!NET_WRITE_BUFFERS && NET_READAHEAD)
default 36 if NET_WRITE_BUFFERS && NET_READAHEAD
default 8 if !NET_WRITE_BUFFERS && !NET_READAHEAD
---help---
Each packet is represented by a series of small I/O buffers in a
chain. This setting determines the number of preallocated I/O
buffers available for packet data.
config IOB_BUFSIZE
int "Payload size of one I/O buffer"
default 196
---help---
Each packet is represented by a series of small I/O buffers in a
chain. This setting determines the data payload each preallocated
I/O buffer.
config IOB_NCHAINS
int "Number of pre-allocated I/O buffer chain heads"
default 0 if !NET_READAHEAD && !NET_UDP_READAHEAD
default 8 if NET_READAHEAD || NET_UDP_READAHEAD
---help---
These tiny nodes are used as "containers" to support queueing of
I/O buffer chains. This will limit the number of I/O transactions
that can be "in-flight" at any give time. The default value of
zero disables this features.
These generic I/O buffer chain containers are not currently used
by any logic in NuttX. That is because their other other specialized
I/O buffer chain containers that also carry a payload of usage
specific information.
config IOB_THROTTLE
int "I/O buffer throttle value"
default 0 if !NET_WRITE_BUFFERS || !NET_READAHEAD
default 8 if NET_WRITE_BUFFERS && NET_READAHEAD
---help---
TCP write buffering and read-ahead buffer use the same pool of free
I/O buffers. In order to prevent uncontrolled incoming TCP packets
from hogging all of the available, pre-allocated I/O buffers, a
throttling value is required. This throttle value assures that
I/O buffers will be denied to the read-ahead logic before TCP writes
are halted.
config IOB_DEBUG
bool "Force I/O buffer debug"
default n
depends on DEBUG_FEATURES && !SYSLOG_BUFFER
---help---
This option will force debug output from I/O buffer logic. This
is not normally something that would want to do but is convenient
if you are debugging the I/O buffer logic and do not want to get
overloaded with other un-related debug output.
NOTE that this selection is not available if IOBs are being used
to syslog buffering logic (CONFIG_SYSLOG_BUFFER=y)!
endif # MM_IOB
endmenu # Common I/O buffer support