From 16ba391e9c6bc26e6f0c950f2117f57b8e542d71 Mon Sep 17 00:00:00 2001 From: Kairui Song Date: Tue, 20 Dec 2022 02:58:39 +0800 Subject: [PATCH] swap: fold swap_ra_clamp_pfn into swap_ra_info This makes the code cleaner. This helper is made of only two line of self explanational code and not reused anywhere else. And this actually make the compiled object smaller by a bit. bloat-o-meter results on x86_64 of mm/swap_state.o: add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-35 (-35) Function old new delta swap_ra_info.constprop 512 477 -35 Total: Before=8388, After=8353, chg -0.42% Link: https://lkml.kernel.org/r/20221219185840.25441-4-ryncsn@gmail.com Signed-off-by: Kairui Song Reviewed-by: "Huang, Ying" Cc: David Hildenbrand Cc: Hugh Dickins Cc: Matthew Wilcox (Oracle) Cc: Miaohe Lin Signed-off-by: Andrew Morton --- mm/swap_state.c | 44 +++++++++++++++++++------------------------- 1 file changed, 19 insertions(+), 25 deletions(-) diff --git a/mm/swap_state.c b/mm/swap_state.c index af8bc12..d8d1711 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -693,28 +693,15 @@ void exit_swap_address_space(unsigned int type) swapper_spaces[type] = NULL; } -static inline void swap_ra_clamp_pfn(struct vm_area_struct *vma, - unsigned long faddr, - unsigned long lpfn, - unsigned long rpfn, - unsigned long *start, - unsigned long *end) -{ - *start = max3(lpfn, PFN_DOWN(vma->vm_start), - PFN_DOWN(faddr & PMD_MASK)); - *end = min3(rpfn, PFN_DOWN(vma->vm_end), - PFN_DOWN((faddr & PMD_MASK) + PMD_SIZE)); -} - static void swap_ra_info(struct vm_fault *vmf, - struct vma_swap_readahead *ra_info) + struct vma_swap_readahead *ra_info) { struct vm_area_struct *vma = vmf->vma; unsigned long ra_val; - unsigned long faddr, pfn, fpfn; + unsigned long faddr, pfn, fpfn, lpfn, rpfn; unsigned long start, end; pte_t *pte, *orig_pte; - unsigned int max_win, hits, prev_win, win, left; + unsigned int max_win, hits, prev_win, win; #ifndef CONFIG_64BIT pte_t *tpte; #endif @@ -742,16 +729,23 @@ static void swap_ra_info(struct vm_fault *vmf, /* Copy the PTEs because the page table may be unmapped */ orig_pte = pte = pte_offset_map(vmf->pmd, faddr); - if (fpfn == pfn + 1) - swap_ra_clamp_pfn(vma, faddr, fpfn, fpfn + win, &start, &end); - else if (pfn == fpfn + 1) - swap_ra_clamp_pfn(vma, faddr, fpfn - win + 1, fpfn + 1, - &start, &end); - else { - left = (win - 1) / 2; - swap_ra_clamp_pfn(vma, faddr, fpfn - left, fpfn + win - left, - &start, &end); + if (fpfn == pfn + 1) { + lpfn = fpfn; + rpfn = fpfn + win; + } else if (pfn == fpfn + 1) { + lpfn = fpfn - win + 1; + rpfn = fpfn + 1; + } else { + unsigned int left = (win - 1) / 2; + + lpfn = fpfn - left; + rpfn = fpfn + win - left; } + start = max3(lpfn, PFN_DOWN(vma->vm_start), + PFN_DOWN(faddr & PMD_MASK)); + end = min3(rpfn, PFN_DOWN(vma->vm_end), + PFN_DOWN((faddr & PMD_MASK) + PMD_SIZE)); + ra_info->nr_pte = end - start; ra_info->offset = fpfn - start; pte -= ra_info->offset; -- 2.7.4