incubator-nuttx/drivers/note/Kconfig

#
# For a description of the syntax of this configuration file,
# see the file kconfig-language.txt in the NuttX tools repository.
#

menu "Note Driver Support"

config DRIVER_NOTE
	bool "Scheduler instrumentation driver"
	default n
	depends on !SCHED_INSTRUMENTATION_CSECTION && (!SCHED_INSTRUMENTATION_SPINLOCK || !SMP)
	---help---
		If this option is selected, then in-memory buffering logic is
		enabled to capture scheduler instrumentation data.  This has
		the advantage that (1) the platform logic does not have to provide
		the sched_note_* interfaces described for the previous settings.
		Instead, the buffering logic catches all of these.  It encodes
		timestamps the scheduler note and adds the note to an in-memory,
		circular buffer.  And (2) buffering the scheduler instrumentation
		data (versus performing some output operation) minimizes the impact
		of the instrumentation on the behavior of the system. If the in-memory
		buffer becomes full, then older notes are overwritten by newer notes.

		A character driver is provided which can be used by an application
		to read data from the in-memory, scheduler instrumentation "note"
		buffer.

		NOTE: This option is not available if critical sections are being
		monitor (nor if spinlocks are being monitored in SMP configuration)
		because there would be a logical error in the design in those cases.
		That error is that these interfaces call enter_ and leave_critical_section
		(and which us spinlocks in SMP mode).  That means that each call to
		sched_note_get() causes several additional entries to be added from
		the note buffer in order to remove one entry.

config SCHED_NOTE_BUFSIZE
	int "Instrumentation buffer size"
	depends on DRIVER_NOTE
	default 2048
	---help---
		The size of the in-memory, circular instrumentation buffer (in
		bytes).

endmenu