util: Add a randomized test for the virtual memory allocator

The test pseudo-randomly makes allocations and deallocations with
the virtual memory allocator and checks that the results are
consistent. Specifically, we test that:

 * no result from the allocator overlaps an already allocated range
 * allocated memory fulfills the stated alignment requirement
 * a failed result from the allocator could not have been fulfilled
 * memory freed to the allocator can later be allocated again

v2: - fix if() in test() to actually run fill()
v3: - add c++11 build flag (Jason)
    - test the full 64-bit range (Jason)

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

configure.ac

@@ -3123,6 +3123,7 @@ AC_CONFIG_FILES([Makefile
                  src/util/Makefile
                  src/util/tests/hash_table/Makefile
                  src/util/tests/string_buffer/Makefile
+                 src/util/tests/vma/Makefile
                  src/util/xmlpool/Makefile
                  src/vulkan/Makefile])
 

src/util/Makefile.am

@@ -22,7 +22,8 @@
 SUBDIRS = . \
 	xmlpool \
 	tests/hash_table \
-	tests/string_buffer
+	tests/string_buffer \
+	tests/vma
 
 include Makefile.sources
 

src/util/meson.build

@@ -159,4 +159,5 @@ if with_tests
 
   subdir('tests/hash_table')
   subdir('tests/string_buffer')
+  subdir('tests/vma')
 endif

src/util/tests/vma/Makefile.am

@@ -0,0 +1,39 @@
+# Copyright © 2018 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.
+
+AM_CPPFLAGS = \
+	-I$(top_srcdir)/include \
+	-I$(top_srcdir)/src/util \
+	$(DEFINES)
+
+TESTS = vma_random_test
+
+check_PROGRAMS = $(TESTS)
+
+vma_random_test_SOURCES = \
+	vma_random_test.cpp
+
+vma_random_test_LDADD = \
+	$(top_builddir)/src/util/libmesautil.la
+
+vma_random_test_CXXFLAGS = $(CXX11_CXXFLAGS)
+
+EXTRA_DIST = meson.build

src/util/tests/vma/meson.build

@@ -0,0 +1,29 @@
+# Copyright © 2018 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 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.
+
+test(
+  'vma_random',
+  executable(
+    'vma_random_test',
+    'vma_random_test.cpp',
+    include_directories : [inc_include, inc_util],
+    link_with : [libmesa_util],
+  )
+)

src/util/tests/vma/vma_random_test.cpp

@@ -0,0 +1,244 @@
+/*
+ * Copyright © 2018 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.
+ */
+
+/* it is a test after all */
+#undef NDEBUG
+
+#include <algorithm>
+#include <cassert>
+#include <climits>
+#include <cstdint>
+#include <cstdio>
+#include <cstdlib>
+#include <random>
+#include <set>
+#include <vector>
+
+#include <err.h>
+
+#include "vma.h"
+
+namespace {
+
+static const uint64_t PAGE_SIZE = 4096;
+
+struct allocation {
+   uint64_t start_page;
+   uint64_t num_pages;
+};
+
+struct allocation_less {
+   bool operator()(const allocation& lhs, const allocation& rhs) const
+   {
+      assert(lhs.start_page + lhs.num_pages > lhs.start_page);
+      return lhs.start_page + lhs.num_pages <= rhs.start_page;
+   }
+};
+
+constexpr uint64_t allocation_end_page(const allocation& a) {
+   return a.start_page + a.num_pages;
+}
+
+struct random_test {
+   static const uint64_t MEM_START_PAGE = 1;
+   static const uint64_t MEM_SIZE = 0xfffffffffffff000;
+   static const uint64_t MEM_PAGES = MEM_SIZE / PAGE_SIZE;
+
+   random_test(uint_fast32_t seed)
+      : heap_holes{allocation{MEM_START_PAGE, MEM_PAGES}}, rand{seed}
+   {
+      util_vma_heap_init(&heap, MEM_START_PAGE * PAGE_SIZE, MEM_SIZE);
+   }
+
+   void test(unsigned long count)
+   {
+      std::uniform_int_distribution<> one_to_thousand(1, 1000);
+      while (count-- > 0) {
+         int action = one_to_thousand(rand);
+         if (action == 1)          fill();
+         else if (action == 2)     empty();
+         else if (action < 374)    dealloc();
+         else                      alloc();
+      }
+   }
+
+   bool alloc(uint64_t size_order=52, uint64_t align_order=52)
+   {
+      std::geometric_distribution<> dist;
+
+      if (align_order > 51)
+         align_order = std::min(dist(rand), 51);
+      uint64_t align_pages = 1ULL << align_order;
+      uint64_t align = align_pages * PAGE_SIZE;
+
+      if (size_order > 51)
+         size_order = std::min(dist(rand), 51);
+      uint64_t size_pages = 1ULL << size_order;
+      uint64_t size = size_pages * PAGE_SIZE;
+
+      uint64_t addr = util_vma_heap_alloc(&heap, size, align);
+
+      if (addr == 0) {
+         /* assert no gaps are present in the tracker that could satisfy this
+          * allocation.
+          */
+         for (const auto& hole : heap_holes) {
+            uint64_t hole_alignment_pages =
+               (align_pages - (hole.start_page % align_pages)) % align_pages;
+            assert(hole.num_pages < size_pages + hole_alignment_pages);
+         }
+         return false;
+      } else {
+         assert(addr % align == 0);
+         uint64_t addr_page = addr / PAGE_SIZE;
+         allocation a{addr_page, size_pages};
+         auto i = heap_holes.find(a);
+         assert(i != end(heap_holes));
+         allocation hole = *i;
+
+         assert(hole.start_page <= addr_page);
+         assert(hole.num_pages >= size_pages + addr_page - hole.start_page);
+
+         heap_holes.erase(i);
+         if (hole.start_page < a.start_page) {
+            heap_holes.emplace(allocation{hole.start_page,
+                     a.start_page - hole.start_page});
+         }
+         if (allocation_end_page(hole) > allocation_end_page(a)) {
+            heap_holes.emplace(allocation{allocation_end_page(a),
+                     allocation_end_page(hole) - allocation_end_page(a)});
+         }
+
+         allocations.push_back(a);
+         return true;
+      }
+   }
+
+   void dealloc()
+   {
+      if (allocations.size() == 0)
+         return;
+
+      std::uniform_int_distribution<> dist(0, allocations.size() - 1);
+      int to_dealloc = dist(rand);
+
+      std::swap(allocations.at(to_dealloc), allocations.back());
+      allocation a = allocations.back();
+      allocations.pop_back();
+
+      util_vma_heap_free(&heap, a.start_page * PAGE_SIZE,
+                         a.num_pages * PAGE_SIZE);
+
+      assert(heap_holes.find(a) == end(heap_holes));
+      auto next = heap_holes.upper_bound(a);
+      if (next != end(heap_holes)) {
+         if (next->start_page == allocation_end_page(a)) {
+            allocation x {a.start_page, a.num_pages + next->num_pages};
+            next = heap_holes.erase(next);
+            next = heap_holes.insert(next, x);
+
+            if (next != begin(heap_holes)) {
+               auto prev = next;
+               prev--;
+               if (allocation_end_page(*prev) == next->start_page) {
+                  allocation x {prev->start_page,
+                        prev->num_pages + next->num_pages};
+
+                  heap_holes.erase(prev);
+                  next = heap_holes.erase(next);
+                  heap_holes.insert(next, x);
+               }
+            }
+
+            return;
+         }
+      }
+
+      if (next != begin(heap_holes)) {
+         auto prev = next;
+         prev--;
+         if (allocation_end_page(*prev) == a.start_page) {
+            allocation x {prev->start_page, prev->num_pages + a.num_pages};
+            next = heap_holes.erase(prev);
+            heap_holes.insert(next, x);
+
+            return;
+         }
+      }
+
+      heap_holes.emplace(a);
+   }
+
+   void fill()
+   {
+      for (int sz = 51; sz >= 0; sz--) {
+         while (alloc(sz, 0))
+            ;
+      }
+      assert(heap_holes.empty());
+   }
+
+   void empty()
+   {
+      while (allocations.size() != 0)
+         dealloc();
+      assert(heap_holes.size() == 1);
+      auto& hole = *begin(heap_holes);
+      assert(hole.start_page == MEM_START_PAGE && hole.num_pages == MEM_PAGES);
+   }
+
+   struct util_vma_heap heap;
+   std::set<allocation, allocation_less> heap_holes;
+   std::default_random_engine rand;
+   std::vector<allocation> allocations;
+};
+
+}
+
+int main(int argc, char **argv)
+{
+   unsigned long seed, count;
+   if (argc == 3) {
+      char *arg_end = NULL;
+      seed = strtoul(argv[1], &arg_end, 0);
+      if (!arg_end || *arg_end || seed == ULONG_MAX)
+         errx(1, "invalid seed \"%s\"", argv[1]);
+
+      arg_end = NULL;
+      count = strtoul(argv[2], &arg_end, 0);
+      if (!arg_end || *arg_end || count == ULONG_MAX)
+         errx(1, "invalid count \"%s\"", argv[2]);
+   } else if (argc == 1) {
+      /* importantly chosen prime numbers. */
+      seed = 8675309;
+      count = 2459;
+   } else {
+      errx(1, "USAGE: %s seed iter_count\n", argv[0]);
+   }
+
+   random_test r{seed};
+   r.test(count);
+
+   printf("ok\n");
+   return 0;
+}