[Mesa-dev] [PATCH 03/65] glsl: Add initial functions to implement an on-disk cache
Timothy Arceri
timothy.arceri at collabora.com
Fri Apr 29 13:33:02 UTC 2016
From: Carl Worth <cworth at cworth.org>
This code provides for an on-disk cache of objects. Objects are stored
and retrieved via names that are arbitrary 20-byte sequences,
(intended to be SHA-1 hashes of something identifying for the
content). The directory used for the cache can be specified by means
of environment variables in the following priority order:
$MESA_GLSL_CACHE_DIR
$XDG_CACHE_HOME/mesa
<user-home-directory>/.cache/mesa
By default the cache will be limited to a maximum size of 1GB. The
environment variable:
$MESA_GLSL_CACHE_MAX_SIZE
can be set (at the time of GL context creation) to choose some other
size. This variable is a number that can optionally be followed by
'K', 'M', or 'G' to select a size in kilobytes, megabytes, or
gigabytes. By default, an unadorned value will be interpreted as
gigabytes.
The cache will be entirely disabled at runtime if the variable
MESA_GLSL_CACHE_DISABLE is set at the time of GL context creation.
This patch is intended to support a future implementation of a shader
cache. But for now, the only code using this cache is the unit tests
included here.
Many thanks to Kristian Høgsberg <krh at bitplanet.net> for the initial
implementation of code that led to this patch. In particular, the idea
of using an mmapped file, (indexed by a portion of the SHA-1), for the
efficent implementation of cache_has_key was entirely his
idea. Kristian also provided some very helpful advice in discussions
regarding various race conditions to be avoided in this code.
Signed-off-by: Timothy Arceri <timothy.arceri at collabora.com>
---
configure.ac | 3 +
docs/envvars.html | 11 +
src/compiler/Makefile.glsl.am | 10 +
src/compiler/Makefile.sources | 4 +
src/compiler/glsl/cache.c | 709 +++++++++++++++++++++++++++++++++++
src/compiler/glsl/cache.h | 172 +++++++++
src/compiler/glsl/tests/.gitignore | 1 +
src/compiler/glsl/tests/cache_test.c | 416 ++++++++++++++++++++
8 files changed, 1326 insertions(+)
create mode 100644 src/compiler/glsl/cache.c
create mode 100644 src/compiler/glsl/cache.h
create mode 100644 src/compiler/glsl/tests/cache_test.c
diff --git a/configure.ac b/configure.ac
index 5f75c60..e47d47f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1230,6 +1230,9 @@ if test "x$with_sha1" = "x"; then
fi
fi
AM_CONDITIONAL([ENABLE_SHADER_CACHE], [test x$enable_shader_cache = xyes])
+if test "x$enable_shader_cache" = "xyes"; then
+ AC_DEFINE([ENABLE_SHADER_CACHE], [1], [Enable shader cache])
+fi
case "$host_os" in
linux*)
diff --git a/docs/envvars.html b/docs/envvars.html
index 253aaf2..02ccfb9 100644
--- a/docs/envvars.html
+++ b/docs/envvars.html
@@ -103,6 +103,17 @@ glGetString(GL_VERSION) for OpenGL ES.
glGetString(GL_SHADING_LANGUAGE_VERSION). Valid values are integers, such as
"130". Mesa will not really implement all the features of the given language version
if it's higher than what's normally reported. (for developers only)
+<li>MESA_GLSL_CACHE_DISABLE - if set, disables the GLSL shader cache
+<li>MESA_GLSL_CACHE_MAX_SIZE - if set, determines the maximum size of
+the on-disk cache of compiled GLSL programs. Should be set to a number
+optionally followed by 'K', 'M', or 'G' to specify a size in
+kilobytes, megabytes, or gigabytes. By default, gigabytes will be
+assumed. And if unset, a maxium size of 1GB will be used.
+<li>MESA_GLSL_CACHE_DIR - if set, determines the directory to be used
+for the on-disk cache of compiled GLSL programs. If this variable is
+not set, then the cache will be stored in $XDG_CACHE_HOME/.mesa (if
+that variable is set), or else within .cache/mesa within the user's
+home directory.
<li>MESA_GLSL - <a href="shading.html#envvars">shading language compiler options</a>
<li>MESA_NO_MINMAX_CACHE - when set, the minmax index cache is globally disabled.
</ul>
diff --git a/src/compiler/Makefile.glsl.am b/src/compiler/Makefile.glsl.am
index daf98f6..045df01 100644
--- a/src/compiler/Makefile.glsl.am
+++ b/src/compiler/Makefile.glsl.am
@@ -32,6 +32,7 @@ EXTRA_DIST += glsl/tests glsl/glcpp/tests glsl/README \
TESTS += glsl/glcpp/tests/glcpp-test \
glsl/glcpp/tests/glcpp-test-cr-lf \
glsl/tests/blob-test \
+ glsl/tests/cache-test \
glsl/tests/general-ir-test \
glsl/tests/optimization-test \
glsl/tests/sampler-types-test \
@@ -45,6 +46,7 @@ check_PROGRAMS += \
glsl/glcpp/glcpp \
glsl/glsl_test \
glsl/tests/blob-test \
+ glsl/tests/cache-test \
glsl/tests/general-ir-test \
glsl/tests/sampler-types-test \
glsl/tests/uniform-initializer-test
@@ -56,6 +58,11 @@ glsl_tests_blob_test_SOURCES = \
glsl_tests_blob_test_LDADD = \
glsl/libglsl.la
+glsl_tests_cache_test_SOURCES = \
+ glsl/tests/cache_test.c
+glsl_tests_cache_test_LDADD = \
+ glsl/libglsl.la
+
glsl_tests_general_ir_test_SOURCES = \
glsl/standalone_scaffolding.cpp \
glsl/tests/builtin_variable_test.cpp \
@@ -120,6 +127,9 @@ glsl_libglsl_la_SOURCES = \
glsl/glsl_parser.h \
$(LIBGLSL_FILES)
+if ENABLE_SHADER_CACHE
+glsl_libglsl_la_SOURCES += $(LIBGLSL_SHADER_CACHE_FILES)
+endif
glsl_compiler_SOURCES = \
$(GLSL_COMPILER_CXX_FILES)
diff --git a/src/compiler/Makefile.sources b/src/compiler/Makefile.sources
index 8915943..3c1735f 100644
--- a/src/compiler/Makefile.sources
+++ b/src/compiler/Makefile.sources
@@ -133,6 +133,10 @@ LIBGLSL_FILES = \
glsl/s_expression.cpp \
glsl/s_expression.h
+LIBGLSL_SHADER_CACHE_FILES = \
+ glsl/cache.c \
+ glsl/cache.h
+
# glsl_compiler
GLSL_COMPILER_CXX_FILES = \
diff --git a/src/compiler/glsl/cache.c b/src/compiler/glsl/cache.c
new file mode 100644
index 0000000..c4c4fb7
--- /dev/null
+++ b/src/compiler/glsl/cache.c
@@ -0,0 +1,709 @@
+/*
+ * Copyright © 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.
+ */
+
+#include <ctype.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/file.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <pwd.h>
+#include <errno.h>
+#include <dirent.h>
+
+#include "util/u_atomic.h"
+#include "util/mesa-sha1.h"
+#include "util/ralloc.h"
+#include "main/errors.h"
+
+#include "cache.h"
+
+/* Number of bits to mask off from a cache key to get an index. */
+#define CACHE_INDEX_KEY_BITS 16
+
+/* Mask for computing an index from a key. */
+#define CACHE_INDEX_KEY_MASK ((1 << CACHE_INDEX_KEY_BITS) - 1)
+
+/* The number of keys that can be stored in the index. */
+#define CACHE_INDEX_MAX_KEYS (1 << CACHE_INDEX_KEY_BITS)
+
+struct program_cache {
+ /* The path to the cache directory. */
+ char *path;
+
+ /* A pointer to the mmapped index file within the cache directory. */
+ uint8_t *index_mmap;
+ size_t index_mmap_size;
+
+ /* Pointer to total size of all objects in cache (within index_mmap) */
+ uint64_t *size;
+
+ /* Pointer to stored keys, (within index_mmap). */
+ uint8_t *stored_keys;
+
+ /* Maximum size of all cached objects (in bytes). */
+ uint64_t max_size;
+};
+
+/* Create a directory named 'path' if it does not already exist.
+ *
+ * Returns: 0 if path already exists as a directory or if created.
+ * -1 in all other cases.
+ */
+static int
+mkdir_if_needed(char *path)
+{
+ struct stat sb;
+
+ /* If the path exists already, then our work is done if it's a
+ * directory, but it's an error if it is not.
+ */
+ if (stat(path, &sb) == 0) {
+ if (S_ISDIR(sb.st_mode)) {
+ return 0;
+ } else {
+ _mesa_warning(NULL,
+ "Cannot use %s for shader cache (not a directory)"
+ "---disabling.\n", path);
+ return -1;
+ }
+ }
+
+ if (mkdir(path, 0755) == 0)
+ return 0;
+
+ _mesa_warning(NULL,
+ "Failed to create %s for shader cache (%s)---disabling.\n",
+ path, strerror(errno));
+
+ return -1;
+}
+
+/* Concatenate an existing path and a new name to form a new path. If the new
+ * path does not exist as a directory, create it then return the resulting
+ * name of the new path (ralloc'ed off of 'ctx').
+ *
+ * Returns NULL on any error, such as:
+ *
+ * <path> does not exist or is not a directory
+ * <path>/<name> exists but is not a directory
+ * <path>/<name> cannot be created as a directory
+ */
+static char *
+concatenate_and_mkdir(void *ctx, char *path, char *name)
+{
+ char *new_path;
+ struct stat sb;
+
+ if (stat(path, &sb) != 0 || ! S_ISDIR(sb.st_mode))
+ return NULL;
+
+ new_path = ralloc_asprintf(ctx, "%s/%s", path, name);
+
+ if (mkdir_if_needed(new_path) == 0)
+ return new_path;
+ else
+ return NULL;
+}
+
+struct program_cache *
+cache_create(void)
+{
+ void *local;
+ struct program_cache *cache = NULL;
+ char *path, *max_size_str;
+ uint64_t max_size;
+ int fd = -1;
+ struct stat sb;
+ size_t size;
+
+ /* A ralloc context for transient data during this invocation. */
+ local = ralloc_context(NULL);
+ if (local == NULL)
+ goto fail;
+
+ /* At user request, disable shader cache entirely. */
+ if (getenv("MESA_GLSL_CACHE_DISABLE"))
+ goto fail;
+
+ /* Determine path for cache based on the first defined name as follows:
+ *
+ * $MESA_GLSL_CACHE_DIR
+ * $XDG_CACHE_HOME/mesa
+ * <pwd.pw_dir>/.cache/mesa
+ */
+ path = getenv("MESA_GLSL_CACHE_DIR");
+ if (path && mkdir_if_needed(path) == -1) {
+ goto fail;
+ }
+
+ if (path == NULL) {
+ char *xdg_cache_home = getenv("XDG_CACHE_HOME");
+
+ if (xdg_cache_home) {
+ if (mkdir_if_needed(xdg_cache_home) == -1)
+ goto fail;
+
+ path = concatenate_and_mkdir(local, xdg_cache_home, "mesa");
+ if (path == NULL)
+ goto fail;
+ }
+ }
+
+ if (path == NULL) {
+ char *buf;
+ size_t buf_size;
+ struct passwd pwd, *result;
+
+ buf_size = sysconf(_SC_GETPW_R_SIZE_MAX);
+ if (buf_size == -1)
+ buf_size = 512;
+
+ /* Loop until buf_size is large enough to query the directory */
+ while (1) {
+ buf = ralloc_size(local, buf_size);
+
+ getpwuid_r(getuid(), &pwd, buf, buf_size, &result);
+ if (result)
+ break;
+
+ if (errno == ERANGE) {
+ ralloc_free(buf);
+ buf = NULL;
+ buf_size *= 2;
+ } else {
+ goto fail;
+ }
+ }
+
+ path = concatenate_and_mkdir(local, pwd.pw_dir, ".cache");
+ if (path == NULL)
+ goto fail;
+
+ path = concatenate_and_mkdir(local, path, "mesa");
+ if (path == NULL)
+ goto fail;
+ }
+
+ cache = ralloc(NULL, struct program_cache);
+ if (cache == NULL)
+ goto fail;
+
+ cache->path = ralloc_strdup(cache, path);
+ if (cache->path == NULL)
+ goto fail;
+
+ path = ralloc_asprintf(local, "%s/index", cache->path);
+ if (path == NULL)
+ goto fail;
+
+ fd = open(path, O_RDWR | O_CREAT | O_CLOEXEC, 0644);
+ if (fd == -1)
+ goto fail;
+
+ if (fstat(fd, &sb) == -1)
+ goto fail;
+
+ /* Force the index file to be the expected size. */
+ size = sizeof(*cache->size) + CACHE_INDEX_MAX_KEYS * CACHE_KEY_SIZE;
+ if (sb.st_size != size) {
+ if (ftruncate(fd, size) == -1)
+ goto fail;
+ }
+
+ /* We map this shared so that other processes see updates that we
+ * make.
+ *
+ * Note: We do use atomic addition to ensure that multiple
+ * processes don't scramble the cache size recorded in the
+ * index. But we don't use any locking to prevent multiple
+ * processes from updating the same entry simultaneously. The idea
+ * is that if either result lands entirely in the index, then
+ * that's equivalent to a well-ordered write followed by an
+ * eviction and a write. On the other hand, if the simultaneous
+ * writes result in a corrupt entry, that's not really any
+ * different than both entries being evicted, (since within the
+ * guarantees of the cryptographic hash, a corrupt entry is
+ * unlikely to ever match a real cache key).
+ */
+ cache->index_mmap = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, 0);
+ if (cache->index_mmap == MAP_FAILED)
+ goto fail;
+ cache->index_mmap_size = size;
+
+ close(fd);
+
+ cache->size = (uint64_t *) cache->index_mmap;
+ cache->stored_keys = cache->index_mmap + sizeof(uint64_t);
+
+ max_size = 0;
+
+ max_size_str = getenv("MESA_GLSL_CACHE_MAX_SIZE");
+ if (max_size_str) {
+ char *end;
+ max_size = strtoul(max_size_str, &end, 10);
+ if (end == max_size_str) {
+ max_size = 0;
+ } else {
+ while (*end && isspace(*end))
+ end++;
+ switch (*end) {
+ case 'K':
+ case 'k':
+ max_size *= 1024;
+ break;
+ case 'M':
+ case 'm':
+ max_size *= 1024*1024;
+ break;
+ case '\0':
+ case 'G':
+ case 'g':
+ default:
+ max_size *= 1024*1024*1024;
+ break;
+ }
+ }
+ }
+
+ /* Default to 1GB for maximum cache size. */
+ if (max_size == 0)
+ max_size = 1024*1024*1024;
+
+ cache->max_size = max_size;
+
+ ralloc_free(local);
+
+ return cache;
+
+ fail:
+ if (fd != -1)
+ close(fd);
+ if (cache)
+ ralloc_free(cache);
+ ralloc_free(local);
+
+ return NULL;
+}
+
+void
+cache_destroy(struct program_cache *cache)
+{
+ munmap(cache->index_mmap, cache->index_mmap_size);
+
+ ralloc_free(cache);
+}
+
+/* Return a filename within the cache's directory corresponding to 'key'. The
+ * returned filename is ralloced with 'cache' as the parent context.
+ *
+ * Returns NULL if out of memory.
+ */
+static char *
+get_cache_file(struct program_cache *cache, cache_key key)
+{
+ char buf[41];
+
+ _mesa_sha1_format(buf, key);
+
+ return ralloc_asprintf(cache, "%s/%c%c/%s",
+ cache->path, buf[0], buf[1], buf + 2);
+}
+
+/* Create the directory that will be needed for the cache file for \key.
+ *
+ * Obviously, the implementation here must closely match
+ * _get_cache_file above.
+*/
+static void
+make_cache_file_directory(struct program_cache *cache, cache_key key)
+{
+ char *dir;
+ char buf[41];
+
+ _mesa_sha1_format(buf, key);
+
+ dir = ralloc_asprintf(cache, "%s/%c%c", cache->path, buf[0], buf[1]);
+
+ mkdir_if_needed(dir);
+
+ ralloc_free(dir);
+}
+
+/* Given a directory path and predicate function, count all entries in
+ * that directory for which the predicate returns true. Then choose a
+ * random entry from among those counted.
+ *
+ * Returns: A malloc'ed string for the path to the chosen file, (or
+ * NULL on any error). The caller should free the string when
+ * finished.
+ */
+static char *
+choose_random_file_matching(const char *dir_path,
+ bool (*predicate)(struct dirent *))
+{
+ DIR *dir;
+ struct dirent *entry;
+ unsigned int count, victim;
+ char *filename;
+
+ dir = opendir(dir_path);
+ if (dir == NULL)
+ return NULL;
+
+ count = 0;
+
+ while (1) {
+ entry = readdir(dir);
+ if (entry == NULL)
+ break;
+ if (! predicate(entry))
+ continue;
+
+ count++;
+ }
+
+ if (count == 0) {
+ closedir(dir);
+ return NULL;
+ }
+
+ victim = rand() % count;
+
+ rewinddir(dir);
+ count = 0;
+
+ while (1) {
+ entry = readdir(dir);
+ if (entry == NULL)
+ break;
+ if (! predicate(entry))
+ continue;
+ if (count == victim)
+ break;
+
+ count++;
+ }
+
+ if (entry == NULL) {
+ closedir(dir);
+ return NULL;
+ }
+
+ asprintf(&filename, "%s/%s", dir_path, entry->d_name);
+
+ closedir(dir);
+
+ return filename;
+}
+
+/* Is entry a regular file, and not having a name with a trailing
+ * ".tmp"
+ */
+static bool
+is_regular_non_tmp_file(struct dirent *entry)
+{
+ size_t len;
+
+ if (entry->d_type != DT_REG)
+ return false;
+
+ len = strlen (entry->d_name);
+ if (len >= 4 && strcmp(&entry->d_name[len-4], ".tmp") == 0)
+ return false;
+
+ return true;
+}
+
+/* Returns the size of the deleted file, (or 0 on any error). */
+static size_t
+unlink_random_file_from_directory(const char *path)
+{
+ struct stat sb;
+ char *filename;
+
+ filename = choose_random_file_matching(path, is_regular_non_tmp_file);
+ if (filename == NULL)
+ return 0;
+
+ if (stat(filename, &sb) == -1) {
+ free (filename);
+ return 0;
+ }
+
+ unlink(filename);
+
+ free (filename);
+
+ return sb.st_size;
+}
+
+/* Is entry a directory with a two-character name, (and not the
+ * special name of "..")
+ */
+static bool
+is_two_character_sub_directory(struct dirent *entry)
+{
+ if (entry->d_type != DT_DIR)
+ return false;
+
+ if (strlen(entry->d_name) != 2)
+ return false;
+
+ if (strcmp(entry->d_name, "..") == 0)
+ return false;
+
+ return true;
+}
+
+static void
+evict_random_item(struct program_cache *cache)
+{
+ const char hex[] = "0123456789abcde";
+ char *dir_path;
+ int a, b;
+ size_t size;
+
+ /* With a reasonably-sized, full cache, (and with keys generated
+ * from a cryptographic hash), we can choose two random hex digits
+ * and reasonably expect the directory to exist with a file in it.
+ */
+ a = rand() % 16;
+ b = rand() % 16;
+
+ asprintf (&dir_path, "%s/%c%c", cache->path, hex[a], hex[b]);
+ if (dir_path == NULL)
+ return;
+
+ size = unlink_random_file_from_directory(dir_path);
+
+ free(dir_path);
+
+ if (size) {
+ p_atomic_add(cache->size, - size);
+ return;
+ }
+
+ /* In the case where the random choice of directory didn't find
+ * something, we choose randomly from the existing directories.
+ *
+ * Really, the only reason this code exists is to allow the unit
+ * tests to work, (which use an artificially-small cache to be able
+ * to force a single cached item to be evicted).
+ */
+ dir_path = choose_random_file_matching(cache->path,
+ is_two_character_sub_directory);
+ if (dir_path == NULL)
+ return;
+
+ size = unlink_random_file_from_directory(dir_path);
+
+ free(dir_path);
+
+ if (size)
+ p_atomic_add(cache->size, - size);
+}
+
+void
+cache_put(struct program_cache *cache,
+ cache_key key,
+ const void *data,
+ size_t size)
+{
+ int fd = -1, fd_final = -1, err, ret;
+ size_t len;
+ char *filename = NULL, *filename_tmp = NULL;
+ const char *p = data;
+
+ filename = get_cache_file(cache, key);
+ if (filename == NULL)
+ goto done;
+
+ /* Write to a temporary file to allow for an atomic rename to the
+ * final destination filename, (to prevent any readers from seeing
+ * a partially written file).
+ */
+ filename_tmp = ralloc_asprintf(cache, "%s.tmp", filename);
+ if (filename_tmp == NULL)
+ goto done;
+
+ fd = open(filename_tmp, O_WRONLY | O_CLOEXEC | O_CREAT, 0644);
+
+ /* Make the two-character subdirectory within the cache as needed. */
+ if (fd == -1) {
+ if (errno != ENOENT)
+ goto done;
+
+ make_cache_file_directory(cache, key);
+
+ fd = open(filename_tmp, O_WRONLY | O_CLOEXEC | O_CREAT, 0644);
+ if (fd == -1)
+ goto done;
+ }
+
+ /* With the temporary file open, we take an exclusive flock on
+ * it. If the flock fails, then another process still has the file
+ * open with the flock held. So just let that file be responsible
+ * for writing the file.
+ */
+ err = flock(fd, LOCK_EX);
+ if (err == -1)
+ goto done;
+
+ /* Now that we have the lock on the open temporary file, we can
+ * check to see if the destination file already exists. If so,
+ * another process won the race between when we saw that the file
+ * didn't exist and now. In this case, we don't do anything more,
+ * (to ensure the size accounting of the cache doesn't get off).
+ */
+ fd_final = open(filename, O_RDONLY | O_CLOEXEC);
+ if (fd_final != -1)
+ goto done;
+
+ /* OK, we're now on the hook to write out a file that we know is
+ * not in the cache, and is also not being written out to the cache
+ * by some other process.
+ *
+ * Before we do that, if the cache is too large, evict something
+ * else first.
+ */
+ if (*cache->size + size > cache->max_size)
+ evict_random_item(cache);
+
+ /* Now, finally, write out the contents to the temporary file, then
+ * rename them atomically to the destination filename, and also
+ * perform an atomic increment of the total cache size.
+ */
+ for (len = 0; len < size; len += ret) {
+ ret = write(fd, p + len, size - len);
+ if (ret == -1) {
+ unlink(filename_tmp);
+ goto done;
+ }
+ }
+
+ rename(filename_tmp, filename);
+
+ p_atomic_add(cache->size, size);
+
+ /* This close finally releases the flock, (now that the final dile
+ * has been renamed into place and the size has been added).
+ */
+ close(fd);
+ fd = -1;
+
+ done:
+ if (filename_tmp)
+ ralloc_free(filename_tmp);
+ if (filename)
+ ralloc_free(filename);
+ if (fd != -1)
+ close(fd);
+}
+
+void *
+cache_get(struct program_cache *cache, cache_key key, size_t *size)
+{
+ int fd = -1, ret, len;
+ struct stat sb;
+ char *filename = NULL;
+ uint8_t *data = NULL;
+
+ if (size)
+ *size = 0;
+
+ filename = get_cache_file(cache, key);
+ if (filename == NULL)
+ goto fail;
+
+ fd = open(filename, O_RDONLY | O_CLOEXEC);
+ if (fd == -1)
+ goto fail;
+
+ if (fstat(fd, &sb) == -1)
+ goto fail;
+
+ data = malloc(sb.st_size);
+ if (data == NULL)
+ goto fail;
+
+ for (len = 0; len < sb.st_size; len += ret) {
+ ret = read(fd, data + len, sb.st_size - len);
+ if (ret == -1)
+ goto fail;
+ }
+
+ ralloc_free(filename);
+ close(fd);
+
+ if (size)
+ *size = sb.st_size;
+
+ return data;
+
+ fail:
+ if (data)
+ free(data);
+ if (filename)
+ ralloc_free(filename);
+ if (fd != -1)
+ close(fd);
+
+ return NULL;
+}
+
+void
+cache_put_key(struct program_cache *cache, cache_key key)
+{
+ uint32_t *key_chunk = (uint32_t *) key;
+ int i = *key_chunk & CACHE_INDEX_KEY_MASK;
+ unsigned char *entry;
+
+ entry = &cache->stored_keys[i + CACHE_KEY_SIZE];
+
+ memcpy(entry, key, CACHE_KEY_SIZE);
+}
+
+/* This function lets us test whether a given key was previously
+ * stored in the cache with cache_put_key(). The implement is
+ * efficient by not using syscalls or hitting the disk. It's not
+ * race-free, but the races are benign. If we race with someone else
+ * calling cache_put_key, then that's just an extra cache miss and an
+ * extra recompile.
+ */
+bool
+cache_has_key(struct program_cache *cache, cache_key key)
+{
+ uint32_t *key_chunk = (uint32_t *) key;
+ int i = *key_chunk & CACHE_INDEX_KEY_MASK;
+ unsigned char *entry;
+
+ entry = &cache->stored_keys[i + CACHE_KEY_SIZE];
+
+ return memcmp(entry, key, CACHE_KEY_SIZE) == 0;
+}
diff --git a/src/compiler/glsl/cache.h b/src/compiler/glsl/cache.h
new file mode 100644
index 0000000..78df32b
--- /dev/null
+++ b/src/compiler/glsl/cache.h
@@ -0,0 +1,172 @@
+/*
+ * Copyright © 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.
+ */
+
+#pragma once
+#ifndef CACHE_H
+#define CACHE_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/* Size of cache keys in bytes. */
+#define CACHE_KEY_SIZE 20
+
+typedef uint8_t cache_key[CACHE_KEY_SIZE];
+
+/* Provide inlined stub functions if the shader cache is disabled. */
+
+#ifdef ENABLE_SHADER_CACHE
+
+/**
+ * Create a new cache object.
+ *
+ * This function creates the handle necessary for all subsequent cache_*
+ * functions.
+ *
+ * This cache provides two distinct operations:
+ *
+ * o Storage and retrieval of arbitrary objects by cryptographic
+ * name (or "key"). This is provided via cache_put() and
+ * cache_get().
+ *
+ * o The ability to store a key alone and check later whether the
+ * key was previously stored. This is provided via cache_put_key()
+ * and cache_has_key().
+ *
+ * The put_key()/has_key() operations are conceptually identical to
+ * put()/get() with no data, but are provided separately to allow for
+ * a more efficient implementation.
+ *
+ * In all cases, the keys are sequences of 20 bytes. It is anticipated
+ * that callers will compute appropriate SHA-1 signatures for keys,
+ * (though nothing in this implementation directly relies on how the
+ * names are computed). See mesa-sha1.h and _mesa_sha1_compute for
+ * assistance in computing SHA-1 signatures.
+ */
+struct program_cache *
+cache_create(void);
+
+/**
+ * Destroy a cache object, (freeing all associated resources).
+ */
+void
+cache_destroy(struct program_cache *cache);
+
+/**
+ * Store an item in the cache under the name \key.
+ *
+ * The item can be retrieved later with cache_get(), (unless the item has
+ * been evicted in the interim).
+ *
+ * Any call to cache_put() may cause an existing, random item to be
+ * evicted from the cache.
+ */
+void
+cache_put(struct program_cache *cache, cache_key key,
+ const void *data, size_t size);
+
+/**
+ * Retrieve an item previously stored in the cache with the name <key>.
+ *
+ * The item must have been previously stored with a call to cache_put().
+ *
+ * If \size is non-NULL, then, on successful return, it will be set to the
+ * size of the object.
+ *
+ * \return A pointer to the stored object if found. NULL if the object
+ * is not found, or if any error occurs, (memory allocation failure,
+ * filesystem error, etc.). The returned data is malloc'ed so the
+ * caller should call free() it when finished.
+ */
+void *
+cache_get(struct program_cache *cache, cache_key key, size_t *size);
+
+/**
+ * Store the name \key within the cache, (without any associated data).
+ *
+ * Later this key can be checked with cache_has_key(), (unless the key
+ * has been evicted in the interim).
+ *
+ * Any call to cache_record() may cause an existing, random key to be
+ * evicted from the cache.
+ */
+void
+cache_put_key(struct program_cache *cache, cache_key key);
+
+/**
+ * Test whether the name \key was previously recorded in the cache.
+ *
+ * Return value: True if cache_put_key() was previously called with
+ * \key, (and the key was not evicted in the interim).
+ *
+ * Note: cache_has_key() will only return true for keys passed to
+ * cache_put_key(). Specifically, a call to cache_put() will not cause
+ * cache_has_key() to return true for the same key.
+ */
+bool
+cache_has_key(struct program_cache *cache, cache_key key);
+
+#else
+
+static inline struct program_cache *
+cache_create(void)
+{
+ return NULL;
+}
+
+static inline void
+cache_put(struct program_cache *cache, cache_key key,
+ const void *data, size_t size)
+{
+ return;
+}
+
+static inline uint8_t *
+cache_get(struct program_cache *cache, cache_key key, size_t *size)
+{
+ return NULL;
+}
+
+static inline void
+cache_put_key(struct program_cache *cache, cache_key key)
+{
+ return;
+}
+
+static inline bool
+cache_has_key(struct program_cache *cache, cache_key key)
+{
+ return false;
+}
+
+#endif /* ENABLE_SHADER_CACHE */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* CACHE_H */
diff --git a/src/compiler/glsl/tests/.gitignore b/src/compiler/glsl/tests/.gitignore
index 13dcdc4..1661ae7 100644
--- a/src/compiler/glsl/tests/.gitignore
+++ b/src/compiler/glsl/tests/.gitignore
@@ -1,4 +1,5 @@
blob-test
+cache-test
ralloc-test
uniform-initializer-test
sampler-types-test
diff --git a/src/compiler/glsl/tests/cache_test.c b/src/compiler/glsl/tests/cache_test.c
new file mode 100644
index 0000000..782bdf9
--- /dev/null
+++ b/src/compiler/glsl/tests/cache_test.c
@@ -0,0 +1,416 @@
+/*
+ * Copyright © 2015 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.
+ */
+
+/* A collection of unit tests for cache.c */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <ftw.h>
+#include <errno.h>
+#include <stdarg.h>
+
+#include "util/mesa-sha1.h"
+#include "cache.h"
+
+bool error = false;
+
+void
+_mesa_warning(void *ctx, const char *fmt, ...);
+
+void
+_mesa_warning(void *ctx, const char *fmt, ...)
+{
+ va_list vargs;
+ (void) ctx;
+
+ va_start(vargs, fmt);
+
+ /* This output is not thread-safe, but that's good enough for the
+ * standalone compiler.
+ */
+ fprintf(stderr, "Mesa warning: ");
+ vfprintf(stderr, fmt, vargs);
+ fprintf(stderr, "\n");
+
+ va_end(vargs);
+}
+
+static void
+expect_equal(uint64_t actual, uint64_t expected, const char *test)
+{
+ if (actual != expected) {
+ fprintf (stderr, "Error: Test '%s' failed: Expected=%ld, Actual=%ld\n",
+ test, expected, actual);
+ error = true;
+ }
+}
+
+static void
+expect_null(void *ptr, const char *test)
+{
+ if (ptr != NULL) {
+ fprintf (stderr, "Error: Test '%s' failed: Result=%p, but expected NULL.\n",
+ test, ptr);
+ error = true;
+ }
+}
+
+static void
+expect_non_null(void *ptr, const char *test)
+{
+ if (ptr == NULL) {
+ fprintf (stderr, "Error: Test '%s' failed: Result=NULL, but expected something else.\n",
+ test);
+ error = true;
+ }
+}
+
+static void
+expect_equal_str(const char *actual, const char *expected, const char *test)
+{
+ if (strcmp(actual, expected)) {
+ fprintf (stderr, "Error: Test '%s' failed:\n\t"
+ "Expected=\"%s\", Actual=\"%s\"\n",
+ test, expected, actual);
+ error = true;
+ }
+}
+
+/* Callback for nftw used in rmrf_local below.
+ */
+static int
+remove_entry(const char *path,
+ const struct stat *sb,
+ int typeflag,
+ struct FTW *ftwbuf)
+{
+ int err = remove(path);
+
+ if (err)
+ fprintf(stderr, "Error removing %s: %s\n", path, strerror(errno));
+
+ return err;
+}
+
+/* Recursively remove a directory.
+ *
+ * This is equivalent to "rm -rf <dir>" with one bit of protection
+ * that the directory name must begin with "." to ensure we don't
+ * wander around deleting more than intended.
+ *
+ * Returns 0 on success, -1 on any error.
+ */
+static int
+rmrf_local(const char *path)
+{
+ if (path == NULL || *path == '\0' || *path != '.')
+ return -1;
+
+ return nftw(path, remove_entry, 64, FTW_DEPTH | FTW_PHYS | FTW_MOUNT);
+}
+
+#define CACHE_TEST_TMP "./cache-test-tmp"
+
+static void
+test_cache_create(void)
+{
+ struct program_cache *cache;
+ int err;
+
+ /* Before doing anything else, ensure that with
+ * MESA_GLSL_CACHE_DISABLE set, that cache_create returns NULL.
+ */
+ setenv("MESA_GLSL_CACHE_DISABLE", "1", 1);
+ cache = cache_create();
+ expect_null(cache, "cache_create with MESA_GLSL_CACHE_DISABLE set");
+
+ unsetenv("MESA_GLSL_CACHE_DISABLE");
+
+ /* For the first real cache_create() clear these environment
+ * variables to test creation of cache in home directory.
+ */
+ unsetenv("MESA_GLSL_CACHE_DIR");
+ unsetenv("XDG_CACHE_HOME");
+
+ cache = cache_create();
+ expect_non_null(cache, "cache_create with no environment variables");
+
+ cache_destroy(cache);
+
+ /* Test with XDG_CACHE_HOME set */
+ setenv("XDG_CACHE_HOME", CACHE_TEST_TMP "/xdg-cache-home", 1);
+ cache = cache_create();
+ expect_null(cache, "cache_create with XDG_CACHE_HOME set with"
+ "a non-existing parent directory");
+
+ mkdir(CACHE_TEST_TMP, 0755);
+ cache = cache_create();
+ expect_non_null(cache, "cache_create with XDG_CACHE_HOME set");
+
+ cache_destroy(cache);
+
+ /* Test with MESA_GLSL_CACHE_DIR set */
+ err = rmrf_local(CACHE_TEST_TMP);
+ expect_equal(err, 0, "Removing " CACHE_TEST_TMP);
+
+ setenv("MESA_GLSL_CACHE_DIR", CACHE_TEST_TMP "/mesa-glsl-cache-dir", 1);
+ cache = cache_create();
+ expect_null(cache, "cache_create with MESA_GLSL_CACHE_DIR set with"
+ "a non-existing parent directory");
+
+ mkdir(CACHE_TEST_TMP, 0755);
+ cache = cache_create();
+ expect_non_null(cache, "cache_create with MESA_GLSL_CACHE_DIR set");
+
+ cache_destroy(cache);
+}
+
+static bool
+does_cache_contain(struct program_cache *cache, cache_key key)
+{
+ void *result;
+
+ result = cache_get(cache, key, NULL);
+
+ if (result) {
+ free (result);
+ return true;
+ }
+
+ return false;
+}
+
+static void
+test_put_and_get(void)
+{
+ struct program_cache *cache;
+ /* If the text of this blob is changed, then blob_key_byte_zero
+ * also needs to be updated.
+ */
+ char blob[] = "This is a blob of thirty-seven bytes";
+ uint8_t blob_key[20];
+ uint8_t blob_key_byte_zero = 0xca;
+ char string[] = "While this string has thirty-four";
+ uint8_t string_key[20];
+ char *result;
+ size_t size;
+ uint8_t *one_KB, *one_MB;
+ uint8_t one_KB_key[20], one_MB_key[20];
+ int count;
+
+ cache = cache_create();
+
+ _mesa_sha1_compute(blob, sizeof(blob), blob_key);
+
+ /* Ensure that cache_get returns nothing before anything is added. */
+ result = cache_get(cache, blob_key, &size);
+ expect_null(result, "cache_get with non-existent item (pointer)");
+ expect_equal(size, 0, "cache_get with non-existent item (size)");
+
+ /* Simple test of put and get. */
+ cache_put(cache, blob_key, blob, sizeof(blob));
+
+ result = cache_get(cache, blob_key, &size);
+ expect_equal_str(blob, result, "cache_get of existing item (pointer)");
+ expect_equal(size, sizeof(blob), "cache_get of existing item (size)");
+
+ free(result);
+
+ /* Test put and get of a second item. */
+ _mesa_sha1_compute(string, sizeof(string), string_key);
+ cache_put(cache, string_key, string, sizeof(string));
+
+ result = cache_get(cache, string_key, &size);
+ expect_equal_str(result, string, "2nd cache_get of existing item (pointer)");
+ expect_equal(size, sizeof(string), "2nd cache_get of existing item (size)");
+
+ free(result);
+
+ /* Set the cache size to 1KB and add a 1KB item to force an eviction. */
+ cache_destroy(cache);
+
+ setenv("MESA_GLSL_CACHE_MAX_SIZE", "1K", 1);
+ cache = cache_create();
+
+ one_KB = calloc(1, 1024);
+
+ /* Obviously the SHA-1 hash of 1024 zero bytes isn't particularly
+ * interesting. But we do have want to take some special care with
+ * the hash we use here. The issue is that in this artificial case,
+ * (with only three files in the cache), the probability is good
+ * that each of the three files will end up in their own
+ * directory. Then, if the directory containing the .tmp file for
+ * the new item being added for cache_put() is the chosen victim
+ * directory for eviction, then no suitable file will be found and
+ * nothing will be evicted.
+ *
+ * That's actually expected given how the eviction code is
+ * implemented, (which expects to only evict once things are more
+ * interestingly full than that).
+ *
+ * For this test, we force this signature to land in the same
+ * directory as the original blob first written to the cache.
+ */
+ _mesa_sha1_compute(one_KB, 1024, one_KB_key);
+ one_KB_key[0] = blob_key_byte_zero;
+
+ cache_put(cache, one_KB_key, one_KB, 1024);
+
+ free (one_KB);
+
+ result = cache_get(cache, one_KB_key, &size);
+ expect_non_null(result, "3rd cache_get of existing item (pointer)");
+ expect_equal(size, 1024, "3rd cache_get of existing item (size)");
+
+ free(result);
+
+ /* Ensure eviction happened by checking that only one of the two
+ * previously-added items can still be fetched.
+ */
+ count = 0;
+ if (does_cache_contain(cache, blob_key))
+ count++;
+
+ if (does_cache_contain(cache, string_key))
+ count++;
+
+ expect_equal(count, 1, "cache_put eviction with MAX_SIZE=1K");
+
+ /* Now increase the size to 1M, add back both items, and ensure all
+ * three that have been added are available via cache_get.
+ */
+ cache_destroy(cache);
+
+ setenv("MESA_GLSL_CACHE_MAX_SIZE", "1M", 1);
+ cache = cache_create();
+
+ cache_put(cache, blob_key, blob, sizeof(blob));
+ cache_put(cache, string_key, string, sizeof(string));
+
+ count = 0;
+ if (does_cache_contain(cache, blob_key))
+ count++;
+
+ if (does_cache_contain(cache, string_key))
+ count++;
+
+ if (does_cache_contain(cache, one_KB_key))
+ count++;
+
+ expect_equal(count, 3, "no eviction before overflow with MAX_SIZE=1M");
+
+ /* Finally, check eviction again after adding an object of size 1M. */
+ one_MB = calloc(1024, 1024);
+
+ _mesa_sha1_compute(one_MB, 1024 * 1024, one_MB_key);
+ one_MB_key[0] = blob_key_byte_zero;;
+
+ cache_put(cache, one_MB_key, one_MB, 1024 * 1024);
+
+ free (one_MB);
+
+ count = 0;
+ if (does_cache_contain(cache, blob_key))
+ count++;
+
+ if (does_cache_contain(cache, string_key))
+ count++;
+
+ if (does_cache_contain(cache, one_KB_key))
+ count++;
+
+ expect_equal(count, 2, "eviction after overflow with MAX_SIZE=1M");
+
+ cache_destroy(cache);
+}
+
+static void
+test_put_key_and_get_key(void)
+{
+ struct program_cache *cache;
+ bool result;
+
+ uint8_t key_a[20] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
+ uint8_t key_b[20] = { 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+ 30, 33, 32, 33, 34, 35, 36, 37, 38, 39};
+ uint8_t key_a_collide[20] =
+ { 0, 1, 42, 43, 44, 45, 46, 47, 48, 49,
+ 50, 55, 52, 53, 54, 55, 56, 57, 58, 59};
+
+ cache = cache_create();
+
+ /* First test that cache_has_key returns false before cache_put_key */
+ result = cache_has_key(cache, key_a);
+ expect_equal(result, 0, "cache_has_key before key added");
+
+ /* Then a couple of tests of cache_put_key followed by cache_has_key */
+ cache_put_key(cache, key_a);
+ result = cache_has_key(cache, key_a);
+ expect_equal(result, 1, "cache_has_key after key added");
+
+ cache_put_key(cache, key_b);
+ result = cache_has_key(cache, key_b);
+ expect_equal(result, 1, "2nd cache_has_key after key added");
+
+ /* Test that a key with the same two bytes as an existing key
+ * forces an eviction.
+ */
+ cache_put_key(cache, key_a_collide);
+ result = cache_has_key(cache, key_a_collide);
+ expect_equal(result, 1, "put_key of a colliding key lands in the cache");
+
+ result = cache_has_key(cache, key_a);
+ expect_equal(result, 0, "put_key of a colliding key evicts from the cache");
+
+ /* And finally test that we can re-add the original key to re-evict
+ * the colliding key.
+ */
+ cache_put_key(cache, key_a);
+ result = cache_has_key(cache, key_a);
+ expect_equal(result, 1, "put_key of original key lands again");
+
+ result = cache_has_key(cache, key_a_collide);
+ expect_equal(result, 0, "put_key of oiginal key evicts the colliding key");
+
+ cache_destroy(cache);
+}
+
+int
+main (void)
+{
+ int err;
+
+ test_cache_create();
+
+ test_put_and_get();
+
+ test_put_key_and_get_key();
+
+ err = rmrf_local(CACHE_TEST_TMP);
+ expect_equal(err, 0, "Removing " CACHE_TEST_TMP " again");
+
+ return error ? 1 : 0;
+}
--
2.5.5
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