On 2022/9/10 3:44, Matthew Wilcox wrote: > On Fri, Sep 09, 2022 at 01:34:52PM +0200, David Hildenbrand wrote: >> On 09.09.22 11:24, Miaohe Lin wrote: >>> @@ -9055,7 +9055,7 @@ void *__init alloc_large_system_hash(const char *tablename, >>> /* It isn't necessary when PAGE_SIZE >= 1MB */ >> >> Huh, how could we ever have that. Smells like dead code. >> >>> if (PAGE_SHIFT < 20) >> >> What about adjusting that as well? The it exactly matches the comment >> >> if (PAGE_SIZE >= SZ_1M) Looks good. Will do it in next version. >> >>> - numentries = round_up(numentries, (1<<20)/PAGE_SIZE); >>> + numentries = round_up(numentries, SZ_1M / PAGE_SIZE); > > The git history provides some clues here. See a7e833182a92. > But we do have an architecture which has ... > > #ifdef CONFIG_PAGE_SIZE_1MB > #define PAGE_SHIFT 20 > #define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_1MB > #endif > > I don't think it's an especially common config. Maybe commit a7e833182a92 fixed a theoretical bug. But IMHO, it might be better to keep the code even if no architecture defines PAGE_SIZE >= 1MB. These codes would be eliminated at compiling time. And once there're architectures with PAGE_SIZE >= 1MB, we still work. Any thoughts? Thanks both. Thanks, Miaohe Lin
