From: compudj Date: Thu, 3 Jun 2004 18:35:48 +0000 (+0000) Subject: events req servicing v2, with background computation X-Git-Tag: v0.12.20~2915 X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=8646cedbd1cba7443c2be4c0225102ab3c3dc8cb;p=lttv.git events req servicing v2, with background computation git-svn-id: http://ltt.polymtl.ca/svn@574 04897980-b3bd-0310-b5e0-8ef037075253 --- diff --git a/ltt/branches/poly/doc/developer/lttvwindow_events_delivery.txt b/ltt/branches/poly/doc/developer/lttvwindow_events_delivery.txt index bbcd8bf3..a3586c0a 100644 --- a/ltt/branches/poly/doc/developer/lttvwindow_events_delivery.txt +++ b/ltt/branches/poly/doc/developer/lttvwindow_events_delivery.txt @@ -144,171 +144,81 @@ void lttvwindow_events_request ( MainWindow *main_win, EventsRequest *events_request); +void lttvwindow_events_request +( MainWindow *main_win, + EventsRequest events_request); -Internal functions : - -- lttvwindow_process_pending_requests - - - -Implementation - - -- Type LttvHooks - -see hook_prio.txt - -The viewers will just have to pass hooks to the main window through this type, -using the hook.h interface to manipulate it. Then, the main window will add -them and remove them from the context to deliver exactly the events requested by -each viewer through process traceset. - - -- lttvwindow_events_request - -It adds the an EventsRequest struct to the array of time requests -pending and registers a pending request for the next g_idle if none is -registered. The viewer can access this structure during the read as its -hook_data. Only the stop_flag can be changed by the viewer through the -event hooks. +void lttvwindow_events_request_remove_all +( MainWindow *main_win, + gpointer viewer); -typedef struct _EventsRequest { - gpointer viewer_data; - LttTime start_time, /* Unset : { 0, 0 } */ - LttvTracesetContextPosition start_position, /* Unset : num_traces = 0 */ - gboolean stop_flag, /* Continue:TRUE Stop:FALSE */ - LttTime end_time, /* Unset : { 0, 0 } */ - guint num_events, /* Unset : G_MAXUINT */ - LttvTracesetContextPosition end_position, /* Unset : num_traces = 0 */ - LttvHooks *before_traceset, /* Unset : NULL */ - LttvHooks *before_trace, /* Unset : NULL */ - LttvHooks *before_tracefile, /* Unset : NULL */ - LttvHooks *event, /* Unset : NULL */ - LttvHooksById *event_by_id, /* Unset : NULL */ - LttvHooks *after_tracefile, /* Unset : NULL */ - LttvHooks *after_trace, /* Unset : NULL */ - LttvHooks *after_traceset /* Unset : NULL */ -} EventsRequest; +Internal functions : - lttvwindow_process_pending_requests -This internal function gets called by g_idle, taking care of the pending -requests. It is responsible for concatenation of time intervals and position -requests. It does it with the following algorithm organizing process traceset -calls. Here is the detailed description of the way it works : +Events Requests Removal -- Events Requests Servicing Algorithm +A new API function will be necessary to let viewers remove all event requests +they have made previously. By allowing this, no more out of bound requests will +be serviced : a viewer that sees its time interval changed before the first +servicing is completed can clear its previous events requests and make a new +one for the new interval needed, considering the finished chunks as completed +area. -Data structures necessary : +It is also very useful for dealing with the viewer destruction case : the viewer +just has to remove its events requests from the main window before it gets +destroyed. -List of requests added to context : list_in -List of requests not added to context : list_out -Initial state : +Permitted GTK Events Between Chunks -list_in : empty -list_out : many events requests +All GTK Events will be enabled between chunks. This is due to the fact that the +background processing and a high priority request are seen as the same case. +While a background processing is in progress, the whole graphical interface must +be enabled. +We needed to deal with the coherence of background processing and diverse GTK +events anyway. This algorithm provides a generalized way to deal with any type +of request and any GTK events. -While list_in !empty and list_out !empty - 1. If list_in is empty (need a seek) - 1.1 Add requests to list_in - 1.1.1 Find all time requests with the lowest start time in list_out - (ltime) - 1.1.2 Find all position requests with the lowest position in list_out - (lpos) - 1.1.3 If lpos.start time < ltime - - Add lpos to list_in, remove them from list_out - 1.1.4 Else, (lpos.start time >= ltime) - - Add ltime to list_in, remove them from list_out - 1.2 Seek - 1.2.1 If first request in list_in is a time request - 1.2.1.1 Seek to that time - 1.2.2 Else, the first request in list_in is a position request - 1.2.2.1 Seek to that position - 1.3 Call begin for all list_in members - (1.3.1 begin hooks called) - (1.3.2 middle hooks added) - 2. Else, list_in is not empty, we continue a read - 2.1 For each req of list_out - - if req.start time == current context time - - Add to list_in, remove from list_out - - Call begin - - if req.start position == current position - - Add to list_in, remove from list_out - - Call begin - 3. Find end criterions - 3.1 End time - 3.1.1 Find lowest end time in list_in - 3.1.2 Find lowest start time in list_out - 3.1.3 Use lowest of both as end time - 3.2 Number of events - 3.2.1 Find lowest number of events in list_in - 3.3 End position - 3.3.1 Find lowest end position in list_in - 3.3.2 Find lowest start position in list_out - 3.3.3 Use lowest of both as end position +Background Computation Request - 4. Call process traceset middle - 4.1 Call process traceset middle (Use end criterion found in 3) - * note : end criterion can also be viewer's hook returning TRUE - 5. After process traceset middle - - if current context time > traceset.end time - - For each req in list_in - - Call end for req - - remove req from list_in - 5.1 For each req in list_in - - req.num -= count - - if req.num == 0 - - Call end for req - - remove req from list_in - - if current context time > req.end time - - Call end for req - - remove req from list_in - - if req.end pos == current pos - - Call end for req - - remove req from list_in - - if req.stop_flag == TRUE - - Call end for req - - remove req from list_in - - - -Notes : -End criterions for process traceset middle : -If the criterion is reached, event is out of boundaries and we return. -Current time >= End time -Event count > Number of events -Current position >= End position -Last hook list called returned TRUE +The types of background computation that can be requested by a viewer : state +computation (main window scope) or viewer specific background computation. -The >= for position is necessary to make ensure consistency between start time -requests and positions requests that happens to be at the exact same start time -and position. +A background computation request is asked via lttvwindow_events_request, with a +priority field set with a low priority. +If a lttvwindow_events_request_remove_all is done on the viewer pointer, it will +not affect the state computation as no viewer pointer will have been passed in +the initial request. This is the expected result. For the background processings +that call viewer's hooks, they will be removed. -Weaknesses -- None (nearly?) :) - - -Strengths +Implementation -- Removes the need for filtering of information supplied to the viewers. -- Viewers have a better control on their data input. +- Type LttvHooks -- Solves all the weaknesses idenfied in the actual boundaryless traceset -reading. +see hook_prio.txt +The viewers will just have to pass hooks to the main window through this type, +using the hook.h interface to manipulate it. Then, the main window will add +them and remove them from the context to deliver exactly the events requested by +each viewer through process traceset. +- lttvwindow_events_request -- Revised Events Requests Servicing Algorithm (v2) +It adds the an EventsRequest struct to the array of time requests +pending and registers a pending request for the next g_idle if none is +registered. The viewer can access this structure during the read as its +hook_data. Only the stop_flag can be changed by the viewer through the +event hooks. typedef LttvEventsRequestPrio guint; @@ -335,6 +245,26 @@ typedef struct _EventsRequest { } EventsRequest; + +- lttvwindow_events_request_remove_all + +It removes all the events requests from the pool that has their "viewer" field +maching the viewer pointer given in argument. + +It calls the traceset/trace/tracefile end hooks for each request removed. + + +- lttvwindow_process_pending_requests + +This internal function gets called by g_idle, taking care of the pending +requests. It is responsible for concatenation of time intervals and position +requests. It does it with the following algorithm organizing process traceset +calls. Here is the detailed description of the way it works : + + + +- Revised Events Requests Servicing Algorithm (v2) + The reads are splitted in chunks. After a chunk is over, we want to check if there is a GTK Event pending and execute it. It can add or remove events requests from the event requests list. If it happens, we want to start over @@ -487,3 +417,23 @@ low priority will loose its state and will have to seek back. It should not occur often. The solution to it would be to save one state per priority. + + + + +Weaknesses + +- None (nearly?) :) + + +Strengths + +- Removes the need for filtering of information supplied to the viewers. + +- Viewers have a better control on their data input. + +- Solves all the weaknesses idenfied in the actual boundaryless traceset +reading. + +- Background processing available. +