diff options
Diffstat (limited to 'compiler-rt/lib/sanitizer_common/sanitizer_linux.h')
| -rw-r--r-- | compiler-rt/lib/sanitizer_common/sanitizer_linux.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux.h b/compiler-rt/lib/sanitizer_common/sanitizer_linux.h index c309e33f81b..522eb092a6d 100644 --- a/compiler-rt/lib/sanitizer_common/sanitizer_linux.h +++ b/compiler-rt/lib/sanitizer_common/sanitizer_linux.h @@ -106,6 +106,17 @@ bool LibraryNameIs(const char *full_name, const char *base_name); // Call cb for each region mapped by map. void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)); +// Releases memory pages entirely within the [beg, end] address range. +// The pages no longer count toward RSS; reads are guaranteed to return 0. +// Requires (but does not verify!) that pages are MAP_PRIVATE. +INLINE void ReleaseMemoryPagesToOSAndZeroFill(uptr beg, uptr end) { + // man madvise on Linux promises zero-fill for anonymous private pages. + // Testing shows the same behaviour for private (but not anonymous) mappings + // of shm_open() files, as long as the underlying file is untouched. + CHECK(SANITIZER_LINUX); + ReleaseMemoryPagesToOS(beg, end); +} + #if SANITIZER_ANDROID #if defined(__aarch64__) |
