`load` does not load (`read` and `compare_exchange` do) so give it a
different name. For the cases where `ptr` was previously the pointer we
were guarding, rename it to `raw`.
If the test happens as uintptr_t on CHERI, then we attempt to construct
a capability and use a capability-based test rather than an
integer-based one, and things go south.
posix_memalign requires that the alignment parameter be a multiple of
sizeof(uintptr_t), but the test begins with alignments as small as
sizeof(size_t). While those are very likely the same value out in the
wild right now, they're not on CHERI.
Begin the test loop at sizeof(uintptr_t) and add a test that a request
for a reasonable amount of memory but with an alignment of
sizeof(uintptr_t)/2 fails with EINVAL.
There are two things calling themselves pagemaps:
- the src/mem/pagemap.h objects of that name
- the SuperslabMap object gets called a PageMap inside the Allocator
Rename the latter to chunkmap, with appropriate case and snake,
everywhere, and pull it out to its own file (chunkmap.h).
The default implementation of a chunkmap is a purely static object, but
we nevertheless instantiate it per allocator, so that other
implementations can use stateful instances when interposing on the
mutation methods. Note that the "get" method, however, must remain
static to support the interface required by Allocator objects.
Used is now set to 1, when the slab is full. This means that the test
for
used - 1 == 0
can be used to detect leaving full, and entering empty, reducing fast
path deallocation branchs by 1.
We know that these are small objects and that they have already had
their cache friendly offsets applied, so jump in to the dealloc path
futher down, below the stats calls.
Split small_dealloc_offseted into a wrapper around the core to avoid
inlining too much into the debug function.
While here, move the handling of the Remote objects into its own block
so that `p` is out of scope thereafter.
Fixes https://github.com/microsoft/snmalloc/issues/98
Debug_check_empty now empties the free lists, and checks it empties all the
queues in the allocator. This does not require statistic tracking to
work anymore.
This additionally can check internal regression that cause leaks that
are not the clients fault.
If the first call to alloc uses the minimum size class, then we end up
leaking a whole page of allocations. We fill the small_fast_free_list,
in a call to build the message_queue. But this means the
small_fast_free_list[0] is not empty. But the code was staying on the
slow path, and overwriting it.
If we are using USE_MALLOC pass through, then ThreadAlloc::get() can
cause an allocation inside snmalloc still, as it builds the thread
local allocator, which allocs a single stub allocator, using
the underlying allocator. This means that ASAN would detect a
leak in a client, even though the client program has none.
This change stops us ever allocating allocators, if we are passing
through calls to an underlying allocator.
