On 2020/5/6 1:25, Matthew Wilcox wrote: > On Tue, May 05, 2020 at 07:55:41PM +0800, Zhen Lei wrote: >> +++ b/mm/swapfile.c >> @@ -177,8 +177,8 @@ static int discard_swap(struct swap_info_struct *si) >> >> /* Do not discard the swap header page! */ >> se = first_se(si); >> - start_block = (se->start_block + 1) << (PAGE_SHIFT - 9); >> - nr_blocks = ((sector_t)se->nr_pages - 1) << (PAGE_SHIFT - 9); >> + start_block = (se->start_block + 1) << SECTORS_PER_PAGE_SHIFT; >> + nr_blocks = ((sector_t)se->nr_pages - 1) << SECTORS_PER_PAGE_SHIFT; > > Thinking about this some more, wouldn't this look better? > > start_block = page_sectors(se->start_block + 1); > nr_block = page_sectors(se->nr_pages - 1); > OK，That's fine, it's clearer. And in this way, there won't be more than 80 columns. > > . >
