Update the lock to i_mmap_rwsem throughout the kernel. All changes are in comments and documentation. Signed-off-by: Davidlohr Bueso <davidlohr.bueso@xxxxxx> --- Documentation/lockstat.txt | 2 +- Documentation/vm/locking | 2 +- arch/x86/mm/hugetlbpage.c | 2 +- include/linux/mmu_notifier.h | 2 +- kernel/events/uprobes.c | 2 +- mm/filemap.c | 10 +++++----- mm/hugetlb.c | 8 ++++---- mm/mmap.c | 6 +++--- mm/mremap.c | 2 +- mm/rmap.c | 8 ++++---- 10 files changed, 22 insertions(+), 22 deletions(-) diff --git a/Documentation/lockstat.txt b/Documentation/lockstat.txt index dd2f7b2..96b8233 100644 --- a/Documentation/lockstat.txt +++ b/Documentation/lockstat.txt @@ -168,7 +168,7 @@ View the top contending locks: dcache_lock: 1037 1161 0.38 45.32 774.51 6611 243371 0.15 306.48 77387.24 &inode->i_mutex: 161 286 18446744073709 62882.54 1244614.55 3653 20598 18446744073709 62318.60 1693822.74 &zone->lru_lock: 94 94 0.53 7.33 92.10 4366 32690 0.29 59.81 16350.06 - &inode->i_data.i_mmap_mutex: 79 79 0.40 3.77 53.03 11779 87755 0.28 116.93 29898.44 + &inode->i_data.i_mmap_rwsem: 79 79 0.40 3.77 53.03 11779 87755 0.28 116.93 29898.44 &q->__queue_lock: 48 50 0.52 31.62 86.31 774 13131 0.17 113.08 12277.52 &rq->rq_lock_key: 43 47 0.74 68.50 170.63 3706 33929 0.22 107.99 17460.62 &rq->rq_lock_key#2: 39 46 0.75 6.68 49.03 2979 32292 0.17 125.17 17137.63 diff --git a/Documentation/vm/locking b/Documentation/vm/locking index f61228b..fb64028 100644 --- a/Documentation/vm/locking +++ b/Documentation/vm/locking @@ -66,7 +66,7 @@ in some cases it is not really needed. Eg, vm_start is modified by expand_stack(), it is hard to come up with a destructive scenario without having the vmlist protection in this case. -The page_table_lock nests with the inode i_mmap_mutex and the kmem cache +The page_table_lock nests with the inode i_mmap_rwsem and the kmem cache c_spinlock spinlocks. This is okay, since the kmem code asks for pages after dropping c_spinlock. The page_table_lock also nests with pagecache_lock and pagemap_lru_lock spinlocks, and no code asks for memory with these locks diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index 9c61a1e..df68d13 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -60,7 +60,7 @@ static int vma_shareable(struct vm_area_struct *vma, unsigned long addr) * and returns the corresponding pte. While this is not necessary for the * !shared pmd case because we can allocate the pmd later as well, it makes the * code much cleaner. pmd allocation is essential for the shared case because - * pud has to be populated inside the same i_mmap_mutex section - otherwise + * pud has to be populated inside the same i_mmap_rwsem section - otherwise * racing tasks could either miss the sharing (see huge_pte_offset) or select a * bad pmd for sharing. */ diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h index deca874..f9c11ab 100644 --- a/include/linux/mmu_notifier.h +++ b/include/linux/mmu_notifier.h @@ -151,7 +151,7 @@ struct mmu_notifier_ops { * Therefore notifier chains can only be traversed when either * * 1. mmap_sem is held. - * 2. One of the reverse map locks is held (i_mmap_mutex or anon_vma->rwsem). + * 2. One of the reverse map locks is held (i_mmap_rwsem or anon_vma->rwsem). * 3. No other concurrent thread can access the list (release) */ struct mmu_notifier { diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index c7b9f45..4ca146e 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -700,7 +700,7 @@ build_map_info(struct address_space *mapping, loff_t offset, bool is_register) if (!prev && !more) { /* - * Needs GFP_NOWAIT to avoid i_mmap_mutex recursion through + * Needs GFP_NOWAIT to avoid i_mmap_rwsem recursion through * reclaim. This is optimistic, no harm done if it fails. */ prev = kmalloc(sizeof(struct map_info), diff --git a/mm/filemap.c b/mm/filemap.c index 7905fe7..5d3ae93 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -60,16 +60,16 @@ /* * Lock ordering: * - * ->i_mmap_mutex (truncate_pagecache) + * ->i_mmap_rwsem (truncate_pagecache) * ->private_lock (__free_pte->__set_page_dirty_buffers) * ->swap_lock (exclusive_swap_page, others) * ->mapping->tree_lock * * ->i_mutex - * ->i_mmap_mutex (truncate->unmap_mapping_range) + * ->i_mmap_rwsem (truncate->unmap_mapping_range) * * ->mmap_sem - * ->i_mmap_mutex + * ->i_mmap_rwsem * ->page_table_lock or pte_lock (various, mainly in memory.c) * ->mapping->tree_lock (arch-dependent flush_dcache_mmap_lock) * @@ -83,7 +83,7 @@ * sb_lock (fs/fs-writeback.c) * ->mapping->tree_lock (__sync_single_inode) * - * ->i_mmap_mutex + * ->i_mmap_rwsem * ->anon_vma.lock (vma_adjust) * * ->anon_vma.lock @@ -103,7 +103,7 @@ * ->inode->i_lock (zap_pte_range->set_page_dirty) * ->private_lock (zap_pte_range->__set_page_dirty_buffers) * - * ->i_mmap_mutex + * ->i_mmap_rwsem * ->tasklist_lock (memory_failure, collect_procs_ao) */ diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 1becd0a..041f58f 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2458,9 +2458,9 @@ void __unmap_hugepage_range_final(struct mmu_gather *tlb, * on its way out. We're lucky that the flag has such an appropriate * name, and can in fact be safely cleared here. We could clear it * before the __unmap_hugepage_range above, but all that's necessary - * is to clear it before releasing the i_mmap_mutex. This works + * is to clear it before releasing the i_mmap_rwsem. This works * because in the context this is called, the VMA is about to be - * destroyed and the i_mmap_mutex is held. + * destroyed and the i_mmap_rwsem is held. */ vma->vm_flags &= ~VM_MAYSHARE; } @@ -3067,9 +3067,9 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, } spin_unlock(&mm->page_table_lock); /* - * Must flush TLB before releasing i_mmap_mutex: x86's huge_pmd_unshare + * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare * may have cleared our pud entry and done put_page on the page table: - * once we release i_mmap_mutex, another task can do the final put_page + * once we release i_mmap_rwsem, another task can do the final put_page * and that page table be reused and filled with junk. */ flush_tlb_range(vma, start, end); diff --git a/mm/mmap.c b/mm/mmap.c index b4e142a..b4ca52a 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -205,7 +205,7 @@ error: } /* - * Requires inode->i_mapping->i_mmap_mutex + * Requires inode->i_mapping->i_mmap_rwsem */ static void __remove_shared_vm_struct(struct vm_area_struct *vma, struct file *file, struct address_space *mapping) @@ -2759,7 +2759,7 @@ void exit_mmap(struct mm_struct *mm) /* Insert vm structure into process list sorted by address * and into the inode's i_mmap tree. If vm_file is non-NULL - * then i_mmap_mutex is taken here. + * then i_mmap_rwsem is taken here. */ int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma) { @@ -3043,7 +3043,7 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping) * vma in this mm is backed by the same anon_vma or address_space. * * We can take all the locks in random order because the VM code - * taking i_mmap_mutex or anon_vma->rwsem outside the mmap_sem never + * taking i_mmap_rwsem or anon_vma->rwsem outside the mmap_sem never * takes more than one of them in a row. Secondly we're protected * against a concurrent mm_take_all_locks() by the mm_all_locks_mutex. * diff --git a/mm/mremap.c b/mm/mremap.c index 02fc5df..742fe28 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -81,7 +81,7 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd, spinlock_t *old_ptl, *new_ptl; /* - * When need_rmap_locks is true, we take the i_mmap_mutex and anon_vma + * When need_rmap_locks is true, we take the i_mmap_rwsem and anon_vma * locks to ensure that rmap will always observe either the old or the * new ptes. This is the easiest way to avoid races with * truncate_pagecache(), page migration, etc... diff --git a/mm/rmap.c b/mm/rmap.c index 98b986d..1bfde51 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -23,7 +23,7 @@ * inode->i_mutex (while writing or truncating, not reading or faulting) * mm->mmap_sem * page->flags PG_locked (lock_page) - * mapping->i_mmap_mutex + * mapping->i_mmap_rwsem * anon_vma->rwsem * mm->page_table_lock or pte_lock * zone->lru_lock (in mark_page_accessed, isolate_lru_page) @@ -804,14 +804,14 @@ static int page_referenced_file(struct page *page, * The page lock not only makes sure that page->mapping cannot * suddenly be NULLified by truncation, it makes sure that the * structure at mapping cannot be freed and reused yet, - * so we can safely take mapping->i_mmap_mutex. + * so we can safely take mapping->i_mmap_rwsem. */ BUG_ON(!PageLocked(page)); i_mmap_lock_read(mapping); /* - * i_mmap_mutex does not stabilize mapcount at all, but mapcount + * i_mmap_rwsem does not stabilize mapcount at all, but mapcount * is more likely to be accurate if we note it after spinning. */ mapcount = page_mapcount(page); @@ -1291,7 +1291,7 @@ out_mlock: /* * We need mmap_sem locking, Otherwise VM_LOCKED check makes * unstable result and race. Plus, We can't wait here because - * we now hold anon_vma->rwsem or mapping->i_mmap_mutex. + * we now hold anon_vma->rwsem or mapping->i_mmap_rwsem. * if trylock failed, the page remain in evictable lru and later * vmscan could retry to move the page to unevictable lru if the * page is actually mlocked. -- 1.7.11.7 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>