(2013/11/29 12:02), Atsushi Kumagai wrote: > On 2013/11/28 16:50:21, kexec <kexec-bounces at lists.infradead.org> wrote: >>>> ping, in case you overlooked this... >>> >>> Sorry for the delayed response, I prioritize the release of v1.5.5 now. >>> >>> Thanks for your advice, check_cyclic_buffer_overrun() should be fixed >>> as you said. In addition, I'm considering other way to address such case, >>> that is to bring the number of "overflowed pages" to the next cycle and >>> exclude them at the top of __exclude_unnecessary_pages() like below: >>> >>> /* >>> * The pages which should be excluded still remain. >>> */ >>> if (remainder >= 1) { >>> int i; >>> unsigned long tmp; >>> for (i = 0; i < remainder; ++i) { >>> if (clear_bit_on_2nd_bitmap_for_kernel(pfn + i)) { >>> pfn_user++; >>> tmp++; >>> } >>> } >>> pfn += tmp; >>> remainder -= tmp; >>> mem_map += (tmp - 1) * SIZE(page); >>> continue; >>> } >>> >>> If this way works well, then aligning info->buf_size_cyclic will be >>> unnecessary. >>> >> >> I selected the current implementation of changing cyclic buffer size becuase >> I thought it was simpler than carrying over remaining filtered pages to next cycle >> in that there was no need to add extra code in filtering processing. >> >> I guess the reason why you think this is better now is how to detect maximum order of >> huge page is hard in some way, right? > > The maximum order will be gotten from HUGETLB_PAGE_ORDER or HPAGE_PMD_ORDER, > so I don't say it's hard. However, the carrying over method doesn't depend on > such kernel symbols, so I think it's robuster. > Then, it's better to remove check_cyclic_buffer_overrun() and rewrite part of free page filtering in __exclude_unnecessary_pages(). Could you do that too? -- Thanks. HATAYAMA, Daisuke