Tetsuo Handa wrote: > Can we manage with allocating only 26 elements when MAX_ORDER + PAGE_SHIFT > > 26 > (e.g. PAGE_SIZE == 256 * 1024) ? > > Can kmalloc_index()/kmalloc_size()/kmalloc_slab() etc. work correctly when > MAX_ORDER + PAGE_SHIFT > 26 (e.g. PAGE_SIZE == 256 * 1024) ? > Today I compared SLAB/SLUB code. If I understood correctly, the line
if (size <= 64 * 1024 * 1024) return 26; in kmalloc_index() is redundant (in fact, kmalloc_caches[26] is out of range) and conflicts with what the comment * The largest kmalloc size supported by the SLAB allocators is * 32 megabyte (2^25) or the maximum allocatable page order if that is * less than 32 MB. says, and 0 <= kmalloc_index() <= 25 is always true for SLAB and 0 <= kmalloc_index() <= PAGE_SHIFT+1 is always true for SLUB. Therefore, towards 3.10-rc1, > > - for (i = 1; i < PAGE_SHIFT + MAX_ORDER; i++) { > > + for (i = 1; i =< KMALLOC_SHIFT_HIGH; i++) { > -+ for (i = 1; i =< KMALLOC_SHIFT_HIGH; i++) { ++ for (i = 1; i <= KMALLOC_SHIFT_HIGH; i++) { would be the last fix for me. (I don't know why kmalloc_caches[0] is excluded.) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/