[Piglit] [PATCH v2 06/24] arb_shader_image_load_store: Import atomicity image built-in tests.
Francisco Jerez
currojerez at riseup.net
Thu Dec 4 04:21:55 PST 2014
Import a number of tests intended to check if the read-modify-write
built-in functions defined by the spec are carried out atomically.
---
tests/all.py | 1 +
.../arb_shader_image_load_store/CMakeLists.gl.txt | 2 +
tests/spec/arb_shader_image_load_store/atomicity.c | 326 +++++++++++++++++++++
3 files changed, 329 insertions(+)
create mode 100644 tests/spec/arb_shader_image_load_store/atomicity.c
diff --git a/tests/all.py b/tests/all.py
index f1f588b..502739b 100644
--- a/tests/all.py
+++ b/tests/all.py
@@ -4299,6 +4299,7 @@ spec['ARB_shader_image_load_store'] = arb_shader_image_load_store
import_glsl_parser_tests(spec['ARB_shader_image_load_store'],
os.path.join(testsDir, 'spec', 'arb_shader_image_load_store'),
[''])
+arb_shader_image_load_store['atomicity'] = PiglitGLTest('arb_shader_image_load_store-atomicity', run_concurrent=True)
profile.tests['hiz'] = hiz
profile.tests['fast_color_clear'] = fast_color_clear
diff --git a/tests/spec/arb_shader_image_load_store/CMakeLists.gl.txt b/tests/spec/arb_shader_image_load_store/CMakeLists.gl.txt
index cc5586d..8c67bb6 100644
--- a/tests/spec/arb_shader_image_load_store/CMakeLists.gl.txt
+++ b/tests/spec/arb_shader_image_load_store/CMakeLists.gl.txt
@@ -12,4 +12,6 @@ link_libraries (
set(depends image.c grid.c common.c)
+piglit_add_executable(arb_shader_image_load_store-atomicity atomicity.c ${depends})
+
# vim: ft=cmake:
diff --git a/tests/spec/arb_shader_image_load_store/atomicity.c b/tests/spec/arb_shader_image_load_store/atomicity.c
new file mode 100644
index 0000000..67f4f39
--- /dev/null
+++ b/tests/spec/arb_shader_image_load_store/atomicity.c
@@ -0,0 +1,326 @@
+/*
+ * Copyright (C) 2014 Intel Corporation
+ *
+ * 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
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * 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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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 atomicity.c
+ *
+ * Test the atomicity of the read-modify-write image operations
+ * defined by the spec. The subtests can be classified in two groups:
+ *
+ * The ones that test bitwise operations (imageAtomicAnd(),
+ * imageAtomicOr(), imageAtomicXor()) work by using an image as bitmap
+ * which is written to by a large number of shader invocations in
+ * parallel, each of them will use a bitwise built-in to flip an
+ * individual bit on the image. If the read-modify-write operation is
+ * implemented atomically no write will overwrite any concurrent write
+ * supposed to flip a different bit in the same dword, so the whole
+ * bitmap will be inverted when the rendering completes.
+ *
+ * The remaining subtests (imageAtomicAdd(), imageAtomicMin(),
+ * imageAtomicMax(), imageAtomicExchange(), imageAtomicCompSwap())
+ * operate on a single 32-bit location of the image which is accessed
+ * concurrently from all shader invocations. In each case a function
+ * written in terms of one of the built-ins is guaranteed to return a
+ * unique 32-bit value for each concurrent invocation as long as the
+ * read-modify-write operation is implemented atomically. The way in
+ * which this is achieved differs for each built-in and is described
+ * in more detail below.
+ */
+
+#include "common.h"
+
+/** Window width. */
+#define W 16
+
+/** Window height. */
+#define H 96
+
+/** Total number of pixels in the window and image. */
+#define N (W * H)
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+config.supports_gl_core_version = 32;
+
+config.window_width = W;
+config.window_height = H;
+config.window_visual = PIGLIT_GL_VISUAL_DOUBLE | PIGLIT_GL_VISUAL_RGBA;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+static bool
+init_image(const struct image_info img, uint32_t v)
+{
+ uint32_t pixels[N];
+
+ return init_pixels(img, pixels, v, 0, 0, 0) &&
+ upload_image(img, 0, pixels);
+}
+
+static bool
+check_fb_unique(const struct grid_info grid)
+{
+ uint32_t pixels[H][W];
+ int frequency[N] = { 0 };
+ int i, j;
+
+ if (!download_result(grid, pixels[0]))
+ return false;
+
+ for (i = 0; i < W; ++i) {
+ for (j = 0; j < H; ++j) {
+ if (frequency[pixels[j][i] % N]++) {
+ printf("Probe value at (%d, %d)\n", i, j);
+ printf(" Observed: 0x%08x\n", pixels[j][i]);
+ printf(" Value not unique.\n");
+ return false;
+ }
+ }
+ }
+
+ return true;
+}
+
+static bool
+check_image_const(const struct image_info img, unsigned n, uint32_t v)
+{
+ uint32_t pixels[N];
+
+ return download_image(img, 0, pixels) &&
+ check_pixels(set_image_size(img, n, 1, 1, 1),
+ pixels, v, 0, 0, 0);
+}
+
+/**
+ * Test skeleton: Init image to \a init_value, run the provided shader
+ * \a op, check that the first \a check_sz pixels of the image equal
+ * \a check_value and optionally check that the resulting fragment
+ * values on the framebuffer are unique.
+ */
+static bool
+run_test(uint32_t init_value, unsigned check_sz, uint32_t check_value,
+ bool check_unique, const char *op)
+{
+ const struct grid_info grid =
+ grid_info(GL_FRAGMENT_SHADER, GL_R32UI, W, H);
+ const struct image_info img =
+ image_info(GL_TEXTURE_1D, GL_R32UI, W, H);
+ GLuint prog = generate_program(
+ grid, GL_FRAGMENT_SHADER,
+ concat(image_hunk(img, ""),
+ hunk("volatile uniform IMAGE_T img;\n"),
+ hunk(op), NULL));
+ bool ret = prog &&
+ init_fb(grid) &&
+ init_image(img, init_value) &&
+ set_uniform_int(prog, "img", 0) &&
+ draw_grid(grid, prog) &&
+ check_image_const(img, check_sz, check_value) &&
+ (!check_unique || check_fb_unique(grid));
+
+ glDeleteProgram(prog);
+ return ret;
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+ enum piglit_result status = PIGLIT_PASS;
+
+ piglit_require_extension("GL_ARB_shader_image_load_store");
+
+ /*
+ * If imageAtomicAdd() is atomic the return values obtained
+ * from each call are guaranteed to be unique.
+ */
+ subtest(&status, true,
+ run_test(0, 1, N, true,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " return GRID_T("
+ " imageAtomicAdd(img, IMAGE_ADDR(ivec2(0)), 1u),"
+ " 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicAdd");
+
+ /*
+ * Call imageAtomicMin() on a fixed location from within a
+ * loop passing the most recent guess of the counter value
+ * decremented by one.
+ *
+ * If no race occurs the counter will be decremented by one
+ * and we're done, if another thread updates the counter in
+ * parallel imageAtomicMin() has no effect since
+ * min(x-n, x-1) = x-n for n >= 1, so we update our guess and
+ * repeat. In the end we obtain a unique counter value for
+ * each fragment if the read-modify-write operation is atomic.
+ */
+ subtest(&status, true,
+ run_test(0xffffffff, 1, 0xffffffff - N, true,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " uint old, v = 0xffffffffu;"
+ "\n"
+ " do {\n"
+ " old = v;\n"
+ " v = imageAtomicMin(img, IMAGE_ADDR(ivec2(0)),"
+ " v - 1u);\n"
+ " } while (v != old);\n"
+ "\n"
+ " return GRID_T(v, 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicMin");
+
+ /*
+ * Use imageAtomicMax() on a fixed location to increment a
+ * counter as explained above for imageAtomicMin(). The
+ * atomicity of the built-in guarantees that the obtained
+ * values will be unique for each fragment.
+ */
+ subtest(&status, true,
+ run_test(0, 1, N, true,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " uint old, v = 0u;"
+ "\n"
+ " do {\n"
+ " old = v;\n"
+ " v = imageAtomicMax(img, IMAGE_ADDR(ivec2(0)),"
+ " v + 1u);\n"
+ " } while (v != old);\n"
+ "\n"
+ " return GRID_T(v, 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicMax");
+
+ /*
+ * Use imageAtomicAnd() to flip individual bits of a bitmap
+ * atomically. The atomicity of the built-in guarantees that
+ * all bits will be clear on termination.
+ */
+ subtest(&status, true,
+ run_test(0xffffffff, N / 32, 0, false,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " int i = IMAGE_ADDR(idx);\n"
+ " uint m = ~(1u << (i % 32));\n"
+ "\n"
+ " imageAtomicAnd(img, i / 32, m);\n"
+ "\n"
+ " return GRID_T(0, 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicAnd");
+
+ /*
+ * Use imageAtomicOr() to flip individual bits of a bitmap
+ * atomically. The atomicity of the built-in guarantees that
+ * all bits will be set on termination.
+ */
+ subtest(&status, true,
+ run_test(0, N / 32, 0xffffffff, false,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " int i = IMAGE_ADDR(idx);\n"
+ " uint m = (1u << (i % 32));\n"
+ "\n"
+ " imageAtomicOr(img, i / 32, m);\n"
+ "\n"
+ " return GRID_T(0, 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicOr");
+
+ /*
+ * Use imageAtomicXor() to flip individual bits of a bitmap
+ * atomically. The atomicity of the built-in guarantees that
+ * all bits will have been inverted on termination.
+ */
+ subtest(&status, true,
+ run_test(0x55555555, N / 32, 0xaaaaaaaa, false,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " int i = IMAGE_ADDR(idx);\n"
+ " uint m = (1u << (i % 32));\n"
+ "\n"
+ " imageAtomicXor(img, i / 32, m);\n"
+ "\n"
+ " return GRID_T(0, 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicXor");
+
+ /*
+ * Use imageAtomicExchange() on a fixed location to increment
+ * a counter, implementing a sort of spin-lock.
+ *
+ * The counter has two states: locked (0xffffffff) and
+ * unlocked (any other value). While locked a single thread
+ * owns the value of the counter, increments its value and
+ * puts it back to the fixed location, atomically releasing
+ * the counter. The atomicity of the built-in guarantees that
+ * the obtained values will be unique for each fragment.
+ *
+ * Unlike the classic spin-lock implementation, we use the
+ * same built-in call to perform either a lock or an unlock
+ * operation depending on the current thread state. This is
+ * critical to avoid a dead-lock situation on machines where
+ * neighboring threads have limited parallelism (e.g. share
+ * the same instruction pointer).
+ */
+ subtest(&status, true,
+ run_test(0, 1, N, true,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " uint p = 0xffffffffu, v = 0xffffffffu;\n"
+ "\n"
+ " do {\n"
+ " if (p != 0xffffffffu)\n"
+ " v = p++;\n"
+ " p = imageAtomicExchange("
+ " img, IMAGE_ADDR(ivec2(0)), p);\n"
+ " } while (v == 0xffffffffu);\n"
+ "\n"
+ " return GRID_T(v, 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicExchange");
+
+ /*
+ * Use imageAtomicCompSwap() on a fixed location from within a
+ * loop passing the most recent guess of the counter value as
+ * comparison value and the same value incremented by one as
+ * argument. The atomicity of the built-in guarantees that
+ * the obtained values will be unique for each fragment.
+ */
+ subtest(&status, true,
+ run_test(0, 1, N, true,
+ "GRID_T op(ivec2 idx, GRID_T x) {\n"
+ " uint old, v = 0u;"
+ "\n"
+ " do {\n"
+ " old = v;\n"
+ " v = imageAtomicCompSwap("
+ " img, IMAGE_ADDR(ivec2(0)), v, v + 1u);\n"
+ " } while (v != old);\n"
+ "\n"
+ " return GRID_T(v, 0, 0, 1);\n"
+ "}\n"),
+ "imageAtomicCompSwap");
+
+ piglit_report_result(status);
+}
+
+enum piglit_result
+piglit_display(void)
+{
+ return PIGLIT_FAIL;
+}
--
2.1.3
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