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    SubjectRe: [PATCH] slob: add size header to all allocations
    On Sun, Oct 17, 2021 at 08:38:41PM -0700, Rustam Kovhaev wrote:
    > Let's prepend all allocations of (PAGE_SIZE - align_offset) and less
    > with the size header. This way kmem_cache_alloc() memory can be freed
    > with kfree() and the other way around, as long as they are less than
    > (PAGE_SIZE - align_offset).

    Hello Rustam, I measured its impact on memory usage on
    tiny kernel configuration as SLOB is used in very small machine.

    on x86 32 bit + tinyconfig:
    Before:
    Slab: 668 kB

    After:
    Slab: 688~692 kB

    it adds 20~24kB.

    >
    > The main reason for this change is to simplify SLOB a little bit, make
    > it a bit easier to debug whenever something goes wrong.
    >

    It seems acceptable But I wonder it is worth to increase memory usage
    to allow freeing kmem_cache_alloc-ed objects by kfree()?

    Thanks,
    Hyeonggon

    > meminfo right after the system boot, without the patch:
    > Slab: 35500 kB
    >
    > the same, with the patch:
    > Slab: 36396 kB
    >

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