small: improve real_size calculation in small_alloc_info
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This patch removes the following ancient declarations: - `size_t small_ptr_compress();` - `void *small_ptr_decompress();`
nshy
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Jul 11, 2025
locker
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Jul 11, 2025
Currently `real_size` is calculated as the size of a memory block that would be allocated for the requested number of bytes. However, this calculation is non-idempotent. For details see commit df7ba1f ("small: implement new allocator strategy"). This patch switches `small_alloc_info()` to `slab_from_ptr()` that returns the actual slab that contains the requested `ptr`, so now `real_size` is always correct. Needed for tarantool/tarantool#10217
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nshy
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Jul 11, 2025
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Currently
real_sizeis calculated as the size of a memory block that would be allocated for the requested number of bytes. However, this calculation is non-idempotent. For details see commit df7ba1f ("small: implement new allocator strategy").This patch switches
small_alloc_info()toslab_from_ptr()that returns the actual slab that contains the requestedptr, so nowreal_sizeis always correct.Needed for tarantool/tarantool#10217
Merge only together with tarantool/tarantool#11652