On Sun, May 09, 2021 at 12:19:40AM +0100, Matthew Wilcox wrote: > On Sun, May 09, 2021 at 07:13:28AM +0900, Hyeonggon Yoo wrote: > > the return value of kmalloc_index is used as index of kmalloc_caches, > > it doesn't matter. every few weeks somebody posts a patch to "optimise" > kmalloc_index, failing to appreciate that it's only ever run at compile > time because it's all under __builtin_constant_p(). Oh thanks, I didn't know about __builtin_constant_p. But I was not optimizing kmalloc_index. isn't it confusing that kmalloc_caches alllows maximum size of 32MB, and kmalloc_index allows maximum size of 64MB? and even if the code I removed is never reached because 64MB is always bigger than KMALLOC_MAX_CACHE_SIZE, it will cause an error if reached.
