Test the overhead of just calling a GL function. The Python script is

a helper to do multiple runs and compare the results.

2 files changed, 289 insertions, 0 deletions

diff --git a/progs/tests/api_speed.c b/progs/tests/api_speed.c
new file mode 100644
index 0000000000..f42c73dfc9
--- /dev/null
+++ b/progs/tests/api_speed.c
@@ -0,0 +1,146 @@
+/*
+ * (C) Copyright IBM Corporation 2002
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * on the rights to use, copy, modify, merge, publish, distribute, sub
+ * license, and/or sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
+ * VA LINUX SYSTEM, IBM AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * \file api_speed.c
+ * Simple test to measure the overhead of making GL calls.
+ * 
+ * The main purpose of this test is to measure the difference in calling
+ * overhead of different dispatch methods.  Since it uses asm/timex.h to
+ * access the Pentium's cycle counters, it will probably only compile on
+ * Linux (though most architectures have a get_cycles function in timex.h).
+ * That is why it isn't in the default Makefile.
+ * 
+ * \author Ian Romanick <idr@us.ibm.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#define GL_GLEXT_PROTOTYPES
+#include <GL/gl.h>
+#include <GL/glext.h>
+#include <GL/glut.h>
+
+#define inline __inline__
+#include <asm/timex.h>
+
+static float Width = 400;
+static float Height = 400;
+static unsigned count = 1000000;
+
+
+static void Idle( void )
+{
+   glutPostRedisplay();
+}
+
+#define DO_FUNC(f,p) \
+   do { \
+      t0 = get_cycles(); \
+      for ( i = 0 ; i < count ; i++ ) { \
+	 f p ; \
+      } \
+      t1 = get_cycles(); \
+      printf("%u calls to % 20s required %llu cycles.\n", count, # f, t1 - t0); \
+   } while( 0 )
+
+/**
+ * Main display function.  This is the place to add more API calls.
+ */
+static void Display( void )
+{
+   int i;
+   const float v[3] = { 1.0, 0.0, 0.0 };
+   cycles_t t0;
+   cycles_t t1;
+
+   glBegin(GL_TRIANGLE_STRIP);
+
+   DO_FUNC( glColor3fv, (v) );
+   DO_FUNC( glNormal3fv, (v) );
+   DO_FUNC( glTexCoord2fv, (v) );
+   DO_FUNC( glTexCoord3fv, (v) );
+   DO_FUNC( glMultiTexCoord2fv, (GL_TEXTURE0, v) );
+   DO_FUNC( glMultiTexCoord2f, (GL_TEXTURE0, 0.0, 0.0) );
+   DO_FUNC( glFogCoordfv, (v) );
+   DO_FUNC( glFogCoordf, (0.5) );
+
+   glEnd();
+
+   exit(0);
+}
+
+
+static void Reshape( int width, int height )
+{
+   Width = width;
+   Height = height;
+   glViewport( 0, 0, width, height );
+   glMatrixMode( GL_PROJECTION );
+   glLoadIdentity();
+   glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
+   glMatrixMode( GL_MODELVIEW );
+   glLoadIdentity();
+}
+
+
+static void Key( unsigned char key, int x, int y )
+{
+   (void) x;
+   (void) y;
+   switch (key) {
+      case 27:
+         exit(0);
+         break;
+   }
+   glutPostRedisplay();
+}
+
+
+int main( int argc, char *argv[] )
+{
+   glutInit( &argc, argv );
+   glutInitWindowSize( (int) Width, (int) Height );
+   glutInitWindowPosition( 0, 0 );
+
+   glutInitDisplayMode( GLUT_RGB );
+
+   glutCreateWindow( argv[0] );
+
+   if ( argc > 1 ) {
+      count = strtoul( argv[1], NULL, 0 );
+      if ( count == 0 ) {
+	 fprintf( stderr, "Usage: %s [iterations]\n", argv[0] );
+	 exit(1);
+      }
+   }
+
+   glutReshapeFunc( Reshape );
+   glutKeyboardFunc( Key );
+   glutDisplayFunc( Display );
+   glutIdleFunc( Idle );
+
+   glutMainLoop();
+   return 0;
+}
diff --git a/progs/tests/api_speed.py b/progs/tests/api_speed.py
new file mode 100755
index 0000000000..d209676261
--- /dev/null
+++ b/progs/tests/api_speed.py
@@ -0,0 +1,143 @@
+#!/usr/bin/env python2
+
+# (C) Copyright IBM Corporation 2004
+# All Rights Reserved.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# on the rights to use, copy, modify, merge, publish, distribute, sub
+# license, and/or sell copies of the Software, and to permit persons to whom
+# the Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice (including the next
+# paragraph) shall be included in all copies or substantial portions of the
+# Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
+# IBM AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+# IN THE SOFTWARE.
+#
+# Authors:
+#    Ian Romanick <idr@us.ibm.com>
+
+
+# This script is used to run api_speed against several different libGL
+# libraries and compare the results.  See the show_usage function for more
+# details on how to use it.
+
+
+import re, os, sys, getopt
+
+class results:
+	def process_file(self, f):
+		self.cycles = {}
+		self.iterations = -1
+
+		for line in f.readlines():
+			m = re.match("(\d+) calls to (.{20}) required (\d+) cycles.", line)
+
+			if self.iterations != -1 and int(m.group(1)) != self.iterations:
+				raise
+
+			# This could be done with lstrip, but the version of
+			# the Python library on my system doesn't have it.
+			# The installed version of Python is quite old. :(
+
+			temp = m.group(2)
+			function_name = None
+			for i in range(len(temp)):
+				if temp[i] != ' ':
+					function_name = temp[i:]
+					break
+
+			if function_name == None:
+				raise
+
+			self.cycles[ function_name ] = int(m.group(3))
+			self.iterations = int(m.group(1))
+
+
+	def show_results(self):
+		for name in self.cycles:
+			print "%s -> %f" % (name, float(self.cycles[name]) / self.iterations)
+
+
+	def compare_results(self, other):
+		for name in self.cycles:
+			if other.cycles.has_key(name):
+				a = float(self.cycles[name])  / self.iterations
+				b = float(other.cycles[name]) / other.iterations
+				p = (100.0 * b / a) - 100.0
+				print "%- 20s %7.2f - %7.2f = % -6.2f (%+.1f%%)" % (name, a, b, a - b, p)
+		return
+
+
+def make_execution_string(lib, iterations):
+	if lib == None:
+		return "./api_speed %u" % (iterations)
+	else:
+		return "LD_PRELOAD=%s ./api_speed %u" % (lib, iterations)
+
+
+def show_usage():
+	print """Usage: %s [-i iterations] {library ...}
+
+The full path to one or more libGL libraries (including the full name of the
+library) can be included on the command-line.  Each library will be tested,
+and the results compared.  The first library listed will be used as the
+"base line" for all comparisons.""" % (sys.argv[0])
+	sys.exit(1)
+
+
+if __name__ == '__main__':
+	try:
+		(args, trail) = getopt.getopt(sys.argv[1:], "i:")
+	except Exception,e:
+		show_usage()
+
+	iterations = 1000000
+	try:
+		for (arg,val) in args:
+			if arg == "-i":
+				iterations = int(val)
+	except Exception,e:
+		show_usage()
+
+
+	result_array = []
+	names = []
+
+
+	# If no libraries were specifically named, just run the test against
+	# the default system libGL.
+
+	if len(trail) == 0:
+		s = make_execution_string( None, iterations )
+		r = results()
+		r.process_file( os.popen(s) )
+		result_array.append(r)
+	else:
+		for lib in trail:
+			s = make_execution_string( lib, iterations )
+			r = results()
+			r.process_file( os.popen(s) )
+			names.append(lib)
+			result_array.append(r)
+
+
+	# If the test was only run against one library, just show the results
+	# of the test run.  Otherwise, compare each successive run against
+	# the first run.
+
+	if len( result_array ) == 1:
+		result_array[0].show_results()
+	else:
+		for i in range(1, len( result_array )):
+			print "%s vs. %s" % (names[0], names[i])
+			result_array[0].compare_results( result_array[i] )
+			print ""