| Message ID | 20221208180209.50845-3-ryncsn@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Clean up and fixes for swap | expand |
Kairui Song <ryncsn@gmail.com> writes: > From: Kairui Song <kasong@tencent.com> > > Avoid a redundant pte map/unmap when swap readahead window is 1. > > Signed-off-by: Kairui Song <kasong@tencent.com> > --- > mm/swap_state.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) Good to reduce the line of code. Thanks! Reviewed-by: "Huang, Ying" <ying.huang@intel.com> > diff --git a/mm/swap_state.c b/mm/swap_state.c > index 438d0676c5be..60136bda78e3 100644 > --- a/mm/swap_state.c > +++ b/mm/swap_state.c > @@ -730,8 +730,6 @@ static void swap_ra_info(struct vm_fault *vmf, > } > > faddr = vmf->address; > - orig_pte = pte = pte_offset_map(vmf->pmd, faddr); > - > fpfn = PFN_DOWN(faddr); > ra_val = GET_SWAP_RA_VAL(vma); > pfn = PFN_DOWN(SWAP_RA_ADDR(ra_val)); > @@ -742,12 +740,11 @@ static void swap_ra_info(struct vm_fault *vmf, > atomic_long_set(&vma->swap_readahead_info, > SWAP_RA_VAL(faddr, win, 0)); > > - if (win == 1) { > - pte_unmap(orig_pte); > + if (win == 1) > return; > - } > > /* 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)
diff --git a/mm/swap_state.c b/mm/swap_state.c index 438d0676c5be..60136bda78e3 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -730,8 +730,6 @@ static void swap_ra_info(struct vm_fault *vmf, } faddr = vmf->address; - orig_pte = pte = pte_offset_map(vmf->pmd, faddr); - fpfn = PFN_DOWN(faddr); ra_val = GET_SWAP_RA_VAL(vma); pfn = PFN_DOWN(SWAP_RA_ADDR(ra_val)); @@ -742,12 +740,11 @@ static void swap_ra_info(struct vm_fault *vmf, atomic_long_set(&vma->swap_readahead_info, SWAP_RA_VAL(faddr, win, 0)); - if (win == 1) { - pte_unmap(orig_pte); + if (win == 1) return; - } /* 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)