add allocators build support and two allocator definitions

The allocators created by the file allocators/BA_allocators.py
are those used in my BA thesis available at: https://muhq.space/ba.html.

allocators/no_falsesharing.py builds patched versions of tcmalloc and
glibc without any allocator inroduced falsesharing.

1 files changed, 22 insertions, 0 deletions

diff --git a/allocators/glibc_2.28_no_passive_falsesharing.patch b/allocators/glibc_2.28_no_passive_falsesharing.patch
new file mode 100644
index 0000000..fcc695c
--- /dev/null
+++ b/allocators/glibc_2.28_no_passive_falsesharing.patch
@@ -0,0 +1,22 @@
+diff --git a/malloc/malloc.c b/malloc/malloc.c
+index 27cf6137c2..3aadaddd1d 100644
+--- a/malloc/malloc.c
++++ b/malloc/malloc.c
+@@ -4172,6 +4172,9 @@ _int_free (mstate av, mchunkptr p, int have_lock)
+ 
+ #if USE_TCACHE
+   {
++    /* Check if chunk is from our own arena.  */
++    if (av == thread_arena)
++      {
+     size_t tc_idx = csize2tidx (size);
+     if (tcache != NULL && tc_idx < mp_.tcache_bins)
+       {
+@@ -4201,6 +4204,7 @@ _int_free (mstate av, mchunkptr p, int have_lock)
+ 	    return;
+ 	  }
+       }
++      }
+   }
+ #endif
+