add starpu_task_footprint function to return a task footprint

doc/chapters/advanced-api.texi

@@ -1034,6 +1034,10 @@ Check if the worker specified by workerid can execute the codelet. Schedulers ne
 Return the current date in µs
 @end deftypefun
 
+@deftypefun uint32_t starpu_task_footprint ({struct starpu_perfmodel *}@var{model}, {struct starpu_task *} @var{task}, {enum starpu_perf_archtype} @var{arch}, unsigned @var{nimpl})
+Returns the footprint for a given task
+@end deftypefun
+
 @deftypefun double starpu_task_expected_length ({struct starpu_task *}@var{task}, {enum starpu_perf_archtype} @var{arch}, unsigned @var{nimpl})
 Returns expected task duration in µs
 @end deftypefun

doc/chapters/advanced-examples.texi

@@ -430,11 +430,14 @@ a name which is different from the execution time performance model.
 
 The application can request time estimations from the StarPU performance
 models by filling a task structure as usual without actually submitting
-it. The data handles can be created by calling @code{starpu_data_register}
-functions with a @code{NULL} pointer (and need to be unregistered as usual)
-and the desired data sizes. The @code{starpu_task_expected_length} and
-@code{starpu_task_expected_power} functions can then be called to get an
-estimation of the task duration on a given arch. @code{starpu_task_destroy}
+it. The data handles can be created by calling @code{starpu_*_data_register}
+functions with a @code{NULL} pointer and @code{-1} node and the
+desired data sizes, and need to be unregistered as usual. The
+@code{starpu_task_expected_length} and @code{starpu_task_expected_power}
+functions can then be called to get an estimation of the task cost on a given
+arch. @code{starpu_task_footprint} can also be used to get the footprint used
+for indexing history-based performance models.
+@code{starpu_task_destroy}
 needs to be called to destroy the dummy task afterwards. See
 @code{tests/perfmodels/regression_based.c} for an example.
 

include/starpu_scheduler.h

@@ -1,6 +1,6 @@
 /* StarPU --- Runtime system for heterogeneous multicore architectures.
  *
- * Copyright (C) 2010-2012  Université de Bordeaux 1
+ * Copyright (C) 2010-2013  Université de Bordeaux 1
  * Copyright (C) 2011  Télécom-SudParis
  *
  * StarPU is free software; you can redistribute it and/or modify
@@ -183,6 +183,8 @@ int starpu_prefetch_task_input_on_node(struct starpu_task *task, unsigned node);
 
 /* Return the current date in us */
 double starpu_timing_now(void);
+/* Returns the perfmodel footprint for the task */
+uint32_t starpu_task_footprint(struct starpu_perfmodel *model, struct starpu_task *task, enum starpu_perf_archtype arch, unsigned nimpl);
 /* Returns expected task duration in us */
 double starpu_task_expected_length(struct starpu_task *task, enum starpu_perf_archtype arch, unsigned nimpl);
 /* Returns an estimated speedup factor relative to CPU speed */

src/datawizard/footprint.c

@@ -1,6 +1,6 @@
 /* StarPU --- Runtime system for heterogeneous multicore architectures.
  *
- * Copyright (C) 2009, 2010-2011  Université de Bordeaux 1
+ * Copyright (C) 2009, 2010-2011, 2013  Université de Bordeaux 1
  * Copyright (C) 2010, 2011, 2012, 2013  Centre National de la Recherche Scientifique
  *
  * StarPU is free software; you can redistribute it and/or modify
@@ -17,6 +17,7 @@
 
 #include <datawizard/footprint.h>
 #include <starpu_hash.h>
+#include <core/task.h>
 
 uint32_t _starpu_compute_buffers_footprint(struct starpu_perfmodel *model, enum starpu_perf_archtype arch, unsigned nimpl, struct _starpu_job *j)
 {
@@ -66,3 +67,9 @@ uint32_t _starpu_compute_data_footprint(starpu_data_handle_t handle)
 
 	return starpu_crc32_be(handle_footprint, interfaceid);
 }
+
+uint32_t starpu_task_footprint(struct starpu_perfmodel *model, struct starpu_task *task, enum starpu_perf_archtype arch, unsigned nimpl)
+{
+	struct _starpu_job *j = _starpu_get_job_associated_to_task(task);
+	return _starpu_compute_buffers_footprint(model, arch, nimpl, j);
+}