[sanitizer] Remove SpinMutexLock from stat function

[vitalybuka]

Summary

Mapped size is more appropriate for most users.

Depends on D111605.

[vitalybuka]

rebase

compiler-rt/lib/sanitizer_common/sanitizer_persistent_allocator.h

 #include "sanitizer_common.h"
 
 namespace __sanitizer {
 
 template <typename T>
 class PersistentAllocator {
  public:
   T *alloc(uptr count = 1);
-  uptr allocated() const {
-    SpinMutexLock l(&mtx);
-    return atomic_load_relaxed(&mapped_size) +
-           atomic_load_relaxed(&region_pos) - atomic_load_relaxed(&region_end);
-  }
+  uptr allocated() const { return atomic_load_relaxed(&mapped_size); }
 
  private:
   T *tryAlloc(uptr count);
   T *refillAndAlloc(uptr count);
   mutable StaticSpinMutex mtx;  // Protects alloc of new blocks.
   atomic_uintptr_t region_pos;  // Region allocator for Node's.
   atomic_uintptr_t region_end;
   atomic_uintptr_t mapped_size;

compiler-rt/lib/sanitizer_common/tests/sanitizer_chained_origin_depot_test.cpp

TEST(SanitizerCommon, ChainedOriginDepotStats) {
   EXPECT_EQ(stats1.n_uniq_ids, stats0.n_uniq_ids + 1);
   EXPECT_GT(stats1.allocated, stats0.allocated);
 
   EXPECT_FALSE(chainedOriginDepot.Put(33, 34, &new_id));
   StackDepotStats stats2 = chainedOriginDepot.GetStats();
   EXPECT_EQ(stats2.n_uniq_ids, stats1.n_uniq_ids);
   EXPECT_EQ(stats2.allocated, stats1.allocated);
 
-  EXPECT_TRUE(chainedOriginDepot.Put(35, 36, &new_id));
+  for (int i = 0; i < 100000; ++i) {
+    ASSERT_TRUE(chainedOriginDepot.Put(35, i, &new_id));
     StackDepotStats stats3 = chainedOriginDepot.GetStats();
-  EXPECT_EQ(stats3.n_uniq_ids, stats2.n_uniq_ids + 1);
-  EXPECT_GT(stats3.allocated, stats2.allocated);
+    ASSERT_EQ(stats3.n_uniq_ids, stats2.n_uniq_ids + 1 + i);
+  }
+  EXPECT_GT(chainedOriginDepot.GetStats().allocated, stats2.allocated);
 }
 
 }  // namespace __sanitizer