[lttv.git] / ltt / branches / poly / doc / developer / hook_prio.txt

Linux Trace Toolkit

Mathieu Desnoyers 18-05-2004


Seeing that a very precise hook call ordering is needed when processing events
(especially the order for calling state update hooks and event delivery hooks),
this document defines a new type and interface that permits to merge all kind of
hooks, eventually sorted by the priority associated to them.

- Type LttvHooks with priorities

This is a modification to the actual LttvHooks that associates a priority with
each hook. The container for this type would be a garray, just like hook.c, but
hooks would be added at the right position in the list, by priority. Hooks in a
hook list are ordered by priority : from highest priority (0) to
lowest (99). The default priority is 50 (defined as LTTV_PRIO_DEFAULT).

A new lttv_hooks_call_merge that will get the hooks from two hook lists in the
right order will deal with the multiple lists priority problem.
Commit	Line	Data
6ea2aecb	1	Linux Trace Toolkit
	2
	3	Mathieu Desnoyers 18-05-2004
	4
	5
	6	Seeing that a very precise hook call ordering is needed when processing events
	7	(especially the order for calling state update hooks and event delivery hooks),
	8	this document defines a new type and interface that permits to merge all kind of
	9	hooks, eventually sorted by the priority associated to them.
	10
b5e8b4a6	11	- Type LttvHooks with priorities
	12
	13	This is a modification to the actual LttvHooks that associates a priority with
	14	each hook. The container for this type would be a garray, just like hook.c, but
1413a5dd	15	hooks would be added at the right position in the list, by priority. Hooks in a
	16	hook list are ordered by priority : from highest priority (0) to
	17	lowest (99). The default priority is 50 (defined as LTTV_PRIO_DEFAULT).
b5e8b4a6	18
1413a5dd	19	A new lttv_hooks_call_merge that will get the hooks from two hook lists in the
1413a5dd	20	right order will deal with the multiple lists priority problem.
b5e8b4a6	21
b5e8b4a6	22
6ea2aecb	23
6ea2aecb	24