mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 10:40:15 +02:00 
			
		
		
		
	mm/pagewalk: remove pgd_entry() and pud_entry()
Currently no user of page table walker sets ->pgd_entry() or ->pud_entry(), so checking their existence in each loop is just wasting CPU cycle. So let's remove it to reduce overhead. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
		
							parent
							
								
									05fbf357d9
								
							
						
					
					
						commit
						0b1fbfe500
					
				
					 2 changed files with 2 additions and 13 deletions
				
			
		| 
						 | 
					@ -1164,8 +1164,6 @@ void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
 | 
				
			||||||
 | 
					
 | 
				
			||||||
/**
 | 
					/**
 | 
				
			||||||
 * mm_walk - callbacks for walk_page_range
 | 
					 * mm_walk - callbacks for walk_page_range
 | 
				
			||||||
 * @pgd_entry: if set, called for each non-empty PGD (top-level) entry
 | 
					 | 
				
			||||||
 * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
 | 
					 | 
				
			||||||
 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
 | 
					 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
 | 
				
			||||||
 *	       this handler is required to be able to handle
 | 
					 *	       this handler is required to be able to handle
 | 
				
			||||||
 *	       pmd_trans_huge() pmds.  They may simply choose to
 | 
					 *	       pmd_trans_huge() pmds.  They may simply choose to
 | 
				
			||||||
| 
						 | 
					@ -1179,10 +1177,6 @@ void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
 | 
				
			||||||
 * (see walk_page_range for more details)
 | 
					 * (see walk_page_range for more details)
 | 
				
			||||||
 */
 | 
					 */
 | 
				
			||||||
struct mm_walk {
 | 
					struct mm_walk {
 | 
				
			||||||
	int (*pgd_entry)(pgd_t *pgd, unsigned long addr,
 | 
					 | 
				
			||||||
			 unsigned long next, struct mm_walk *walk);
 | 
					 | 
				
			||||||
	int (*pud_entry)(pud_t *pud, unsigned long addr,
 | 
					 | 
				
			||||||
	                 unsigned long next, struct mm_walk *walk);
 | 
					 | 
				
			||||||
	int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
 | 
						int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
 | 
				
			||||||
			 unsigned long next, struct mm_walk *walk);
 | 
								 unsigned long next, struct mm_walk *walk);
 | 
				
			||||||
	int (*pte_entry)(pte_t *pte, unsigned long addr,
 | 
						int (*pte_entry)(pte_t *pte, unsigned long addr,
 | 
				
			||||||
| 
						 | 
					
 | 
				
			||||||
| 
						 | 
					@ -86,9 +86,7 @@ static int walk_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 | 
				
			||||||
				break;
 | 
									break;
 | 
				
			||||||
			continue;
 | 
								continue;
 | 
				
			||||||
		}
 | 
							}
 | 
				
			||||||
		if (walk->pud_entry)
 | 
							if (walk->pmd_entry || walk->pte_entry)
 | 
				
			||||||
			err = walk->pud_entry(pud, addr, next, walk);
 | 
					 | 
				
			||||||
		if (!err && (walk->pmd_entry || walk->pte_entry))
 | 
					 | 
				
			||||||
			err = walk_pmd_range(pud, addr, next, walk);
 | 
								err = walk_pmd_range(pud, addr, next, walk);
 | 
				
			||||||
		if (err)
 | 
							if (err)
 | 
				
			||||||
			break;
 | 
								break;
 | 
				
			||||||
| 
						 | 
					@ -237,10 +235,7 @@ int walk_page_range(unsigned long addr, unsigned long end,
 | 
				
			||||||
			pgd++;
 | 
								pgd++;
 | 
				
			||||||
			continue;
 | 
								continue;
 | 
				
			||||||
		}
 | 
							}
 | 
				
			||||||
		if (walk->pgd_entry)
 | 
							if (walk->pmd_entry || walk->pte_entry)
 | 
				
			||||||
			err = walk->pgd_entry(pgd, addr, next, walk);
 | 
					 | 
				
			||||||
		if (!err &&
 | 
					 | 
				
			||||||
		    (walk->pud_entry || walk->pmd_entry || walk->pte_entry))
 | 
					 | 
				
			||||||
			err = walk_pud_range(pgd, addr, next, walk);
 | 
								err = walk_pud_range(pgd, addr, next, walk);
 | 
				
			||||||
		if (err)
 | 
							if (err)
 | 
				
			||||||
			break;
 | 
								break;
 | 
				
			||||||
| 
						 | 
					
 | 
				
			||||||
		Loading…
	
		Reference in a new issue