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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: zcf6pmo1a7utkqgzxhszune1adr5brks X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: C512C1A0009 X-Rspam-User: X-HE-Tag: 1745908905-118110 X-HE-Meta: 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 pA5vrXc5 FzriktSe4aQ9+ePfyFPCiYnztKQQf24fz9CZx70DNNuB3eV8M0wEnzQ5TTPmoGFcnlqoYzx1buhZaGAt/yrlm/XFT8ZpRR/OBDefVQmC0cFwtJdmVSamHf8LRzI+T5d8lqhbO6+PZT6mJ9bGsM70eA1DoIlnc8GrfcLwnnnu0NFBFcXi5R9QXe3SqdhRZXgtmGNvywpJX8RZjobE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/29/25 10:53, Dev Jain wrote: > Reduce indentation in change_pte_range() by refactoring some of the code > into a new function. No functional change. > > Signed-off-by: Dev Jain > --- > mm/mprotect.c | 116 +++++++++++++++++++++++++++++--------------------- > 1 file changed, 68 insertions(+), 48 deletions(-) > > diff --git a/mm/mprotect.c b/mm/mprotect.c > index 88608d0dc2c2..70f59aa8c2a8 100644 > --- a/mm/mprotect.c > +++ b/mm/mprotect.c > @@ -83,6 +83,71 @@ bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr, > return pte_dirty(pte); > } > > + > + > +static bool prot_numa_skip(struct vm_area_struct *vma, struct folio *folio, > + int target_node) > +{ > + bool toptier; > + int nid; > + > + /* Also skip shared copy-on-write pages */ > + if (is_cow_mapping(vma->vm_flags) && > + (folio_maybe_dma_pinned(folio) || > + folio_maybe_mapped_shared(folio))) > + return true; > + > + /* > + * While migration can move some dirty pages, > + * it cannot move them all from MIGRATE_ASYNC > + * context. > + */ > + if (folio_is_file_lru(folio) && > + folio_test_dirty(folio)) > + return true; > + > + /* > + * Don't mess with PTEs if page is already on the node > + * a single-threaded process is running on. > + */ > + nid = folio_nid(folio); > + if (target_node == nid) > + return true; > + toptier = node_is_toptier(nid); > + > + /* > + * Skip scanning top tier node if normal numa > + * balancing is disabled > + */ > + if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_NORMAL) && > + toptier) > + return true; > + return false; > +} > + > +static bool prot_numa_avoid_fault(struct vm_area_struct *vma, > + unsigned long addr, pte_t oldpte, int target_node) > +{ > + struct folio *folio; > + int ret; > + > + /* Avoid TLB flush if possible */ > + if (pte_protnone(oldpte)) > + return true; > + > + folio = vm_normal_folio(vma, addr, oldpte); > + if (!folio || folio_is_zone_device(folio) || > + folio_test_ksm(folio)) > + return true; > + ret = prot_numa_skip(vma, folio, target_node); What purpose does it solve to create additional helper prot_numa_skip(). IOW - why cannot all of these be inside prot_numa_avoid_fault() itself. > + if (ret) > + return ret; > + if (folio_use_access_time(folio)) > + folio_xchg_access_time(folio, > + jiffies_to_msecs(jiffies)); > + return false; > +} > + > static long change_pte_range(struct mmu_gather *tlb, > struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, > unsigned long end, pgprot_t newprot, unsigned long cp_flags) > @@ -116,56 +181,11 @@ static long change_pte_range(struct mmu_gather *tlb, > * Avoid trapping faults against the zero or KSM > * pages. See similar comment in change_huge_pmd. > */ > - if (prot_numa) { > - struct folio *folio; > - int nid; > - bool toptier; > - > - /* Avoid TLB flush if possible */ > - if (pte_protnone(oldpte)) > - continue; > - > - folio = vm_normal_folio(vma, addr, oldpte); > - if (!folio || folio_is_zone_device(folio) || > - folio_test_ksm(folio)) > - continue; > - > - /* Also skip shared copy-on-write pages */ > - if (is_cow_mapping(vma->vm_flags) && > - (folio_maybe_dma_pinned(folio) || > - folio_maybe_mapped_shared(folio))) > - continue; > - > - /* > - * While migration can move some dirty pages, > - * it cannot move them all from MIGRATE_ASYNC > - * context. > - */ > - if (folio_is_file_lru(folio) && > - folio_test_dirty(folio)) > + if (prot_numa && > + prot_numa_avoid_fault(vma, addr, > + oldpte, target_node)) > continue; > > - /* > - * Don't mess with PTEs if page is already on the node > - * a single-threaded process is running on. > - */ > - nid = folio_nid(folio); > - if (target_node == nid) > - continue; > - toptier = node_is_toptier(nid); > - > - /* > - * Skip scanning top tier node if normal numa > - * balancing is disabled > - */ > - if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_NORMAL) && > - toptier) > - continue; > - if (folio_use_access_time(folio)) > - folio_xchg_access_time(folio, > - jiffies_to_msecs(jiffies)); > - } > - > oldpte = ptep_modify_prot_start(vma, addr, pte); > ptent = pte_modify(oldpte, newprot); >