[all-commits] [llvm/llvm-project] 93b470: [compiler-rt][fuchsia] Preallocate a vmar for sani...

[PiJoules via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 93b47053c6bce5862ba4a5f7d9f6d5cbaa8cbf41
      https://github.com/llvm/llvm-project/commit/93b47053c6bce5862ba4a5f7d9f6d5cbaa8cbf41
  Author: PiJoules <6019989+PiJoules at users.noreply.github.com>
  Date:   2024-01-11 (Thu, 11 Jan 2024)

  Changed paths:
    M compiler-rt/lib/sanitizer_common/sanitizer_fuchsia.cpp

  Log Message:
  -----------
  [compiler-rt][fuchsia] Preallocate a vmar for sanitizer internals (#75256)

In an effort to reduce more mmap fragmentation, allocate a large enough
vmar where we can map sanitizer internals via DoAnonymousMmap. Objects
being mapped here include asan's FakeStack, LowLevelAllocator mappings,
the primary allocator's TwoLevelMap, InternalMmapVector, StackStore, and
asan's thread internals. The vmar is large enough to hold the total size
of these objects seen in a "typical" process lifetime. If the vmar is
full, it will fallback to mapping in the root vmar.