diff options
| -rw-r--r-- | include/linux/rmap.h | 15 | ||||
| -rw-r--r-- | mm/ksm.c | 7 | ||||
| -rw-r--r-- | mm/rmap.c | 37 |
3 files changed, 51 insertions, 8 deletions
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 6a456ce6de20..616aa4d05f0a 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -235,10 +235,25 @@ struct anon_vma *page_lock_anon_vma_read(struct page *page); void page_unlock_anon_vma_read(struct anon_vma *anon_vma); int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma); +/* + * rmap_walk_control: To control rmap traversing for specific needs + * + * arg: passed to rmap_one() and invalid_vma() + * rmap_one: executed on each vma where page is mapped + * done: for checking traversing termination condition + * file_nonlinear: for handling file nonlinear mapping + * anon_lock: for getting anon_lock by optimized way rather than default + * invalid_vma: for skipping uninterested vma + */ struct rmap_walk_control { void *arg; int (*rmap_one)(struct page *page, struct vm_area_struct *vma, unsigned long addr, void *arg); + int (*done)(struct page *page); + int (*file_nonlinear)(struct page *, struct address_space *, + struct vm_area_struct *vma); + struct anon_vma *(*anon_lock)(struct page *page); + bool (*invalid_vma)(struct vm_area_struct *vma, void *arg); }; /* @@ -2032,12 +2032,19 @@ again: if ((rmap_item->mm == vma->vm_mm) == search_new_forks) continue; + if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) + continue; + ret = rwc->rmap_one(page, vma, rmap_item->address, rwc->arg); if (ret != SWAP_AGAIN) { anon_vma_unlock_read(anon_vma); goto out; } + if (rwc->done && rwc->done(page)) { + anon_vma_unlock_read(anon_vma); + goto out; + } } anon_vma_unlock_read(anon_vma); } diff --git a/mm/rmap.c b/mm/rmap.c index f8f10ad5d359..97bf8f0396f8 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1684,10 +1684,14 @@ void __put_anon_vma(struct anon_vma *anon_vma) } #ifdef CONFIG_MIGRATION -static struct anon_vma *rmap_walk_anon_lock(struct page *page) +static struct anon_vma *rmap_walk_anon_lock(struct page *page, + struct rmap_walk_control *rwc) { struct anon_vma *anon_vma; + if (rwc->anon_lock) + return rwc->anon_lock(page); + /* * Note: remove_migration_ptes() cannot use page_lock_anon_vma_read() * because that depends on page_mapped(); but not all its usages @@ -1713,16 +1717,22 @@ static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc) struct anon_vma_chain *avc; int ret = SWAP_AGAIN; - anon_vma = rmap_walk_anon_lock(page); + anon_vma = rmap_walk_anon_lock(page, rwc); if (!anon_vma) return ret; anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) { struct vm_area_struct *vma = avc->vma; unsigned long address = vma_address(page, vma); + + if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) + continue; + ret = rwc->rmap_one(page, vma, address, rwc->arg); if (ret != SWAP_AGAIN) break; + if (rwc->done && rwc->done(page)) + break; } anon_vma_unlock_read(anon_vma); return ret; @@ -1740,15 +1750,26 @@ static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc) mutex_lock(&mapping->i_mmap_mutex); vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { unsigned long address = vma_address(page, vma); + + if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) + continue; + ret = rwc->rmap_one(page, vma, address, rwc->arg); if (ret != SWAP_AGAIN) - break; + goto done; + if (rwc->done && rwc->done(page)) + goto done; } - /* - * No nonlinear handling: being always shared, nonlinear vmas - * never contain migration ptes. Decide what to do about this - * limitation to linear when we need rmap_walk() on nonlinear. - */ + + if (!rwc->file_nonlinear) + goto done; + + if (list_empty(&mapping->i_mmap_nonlinear)) + goto done; + + ret = rwc->file_nonlinear(page, mapping, vma); + +done: mutex_unlock(&mapping->i_mmap_mutex); return ret; } |