diff options
| -rw-r--r-- | unittests/KDAlloc/rusage.cpp | 43 |
1 files changed, 25 insertions, 18 deletions
diff --git a/unittests/KDAlloc/rusage.cpp b/unittests/KDAlloc/rusage.cpp index fa755b73..453c5e5d 100644 --- a/unittests/KDAlloc/rusage.cpp +++ b/unittests/KDAlloc/rusage.cpp @@ -11,7 +11,7 @@ #include "gtest/gtest.h" -#include <deque> +#include <vector> #include <sys/resource.h> @@ -20,7 +20,7 @@ #if !defined(__has_feature) || \ (!__has_feature(memory_sanitizer) && !__has_feature(address_sanitizer)) -std::size_t write_to_allocations(std::deque<void *> &allocations) { +std::size_t write_to_allocations(std::vector<void *> &allocations) { struct rusage ru; getrusage(RUSAGE_SELF, &ru); auto initial = ru.ru_minflt; @@ -41,26 +41,33 @@ TEST(KDAllocTest, Rusage) { 0); // 1 GB klee::kdalloc::Allocator allocator = factory.makeAllocator(); - std::deque<void *> allocations; + std::vector<void *> allocations; for (std::size_t i = 0; i < 1000; ++i) { - auto p = allocator.allocate(16); - allocations.emplace_back(p); + allocations.emplace_back(allocator.allocate(16)); } - auto pageFaults = write_to_allocations(allocations); - - ASSERT_GT(pageFaults, static_cast<std::size_t>(0)) - << "No page faults happened"; - ASSERT_EQ(pageFaults, allocations.size()) - << "Number of (minor) page faults and objects differs"; - - factory.getMapping().clear(); - - // try again: this should (again) trigger a minor page fault for every object - auto pageFaultsSecondTry = write_to_allocations(allocations); + // When writing to allocations we should have at least one page fault per + // object, but may have more due to unrelated behavior (e.g., swapping). In + // the hopes that such interference is relatively rare, we try a few times to + // encounter a perfect run, where the number of page faults matches the number + // of allocated objects exactly. + constexpr std::size_t tries = 100; + for (std::size_t i = 0; i < tries; ++i) { + auto pageFaults = write_to_allocations(allocations); + if (pageFaults == allocations.size()) { + // we have a perfect match + return; + } + + ASSERT_GE(pageFaults, allocations.size()) + << "There should be at least as many page faults as allocated objects"; + + factory.getMapping().clear(); + } - ASSERT_EQ(pageFaults, pageFaultsSecondTry) - << "Number of minor page faults in second try differs"; + FAIL() + << "No single try out of " << tries + << " yielded a perfect match between page faults and allocated objects"; } #endif |