After commit 8a6b02b5bf ("lib/os/heap: some code simplification in
sys_heap_aligned_alloc()") it is no longer required to have a "big"
heap for aligned allocations to work on 32-bit targets. While the
natural alignment for returned memory has an offset of 4 within a chunk
unit due to the smaller header size, returning to a chunkid from a
memory pointer with an offset of 8 will fall back onto the proper chunk
number once the 4 is substracted and then divided by 8.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Many issues:
- heapmem[] is of type uint64_t meaning that it contains HEAP_SZ * 16
bytes but the heap is initialized with only 1/16 of that, making
this test's memory footprint way too large.
- The test to ensure the heap is empty uses an allocation size of
(heap_end - heap_start - 8) which is wrong as heap_end and heap_start
are uint64_t pointer types and therefore their difference will be 8x
smaller than intended. Furthermore, the 8 here is unnessary as the
chunk header size is already included in the location of heap_start.
- The heap start address misalignment bare no purpose as the misaligned
start of the free heap is already controlled by the variable prefix
allocation size.
- Alignment and sizes should rather be expressed in terms of size_t
rather than uintptr_t.
Fix those issues, and add a few more test angles:
- Make the prefix allocation itterate across the entire alignment range
to exercize all possible misalignments.
- Vary the aligned allocation size to better exercize the pre-alignment
allocation and suffix handling.
- Double the aligned allocation to add more variability in the heap
structure.
- Test the testing of emptiness by making sure that no more allocations
are possible when we think we allocated it all.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Test of the sys_heap_aligned_alloc() API. This is separate from the
existing heap test because aligned_alloc() requires a kconfig to
enable it that can change the heap block header format and will impact
code coverage of the "small" block variant.
It's a fairly simple whitebox test that instantiates a heap and then
enumerates all possible alignments within it, with and without
pre-allocated data, to verify that the resulting memory is correctly
aligned and the heap stays consistent.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
