iw_cxgb4: handle draining an idle qp

[deliverable/linux.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index 4a0f5fa79dbd552dd2ccd34480f494483646e339..a8c69c8c0a90a1e50cfdc822ce2cbc3854e0c8e8 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -101,7 +101,7 @@
  *    ->tree_lock              (page_remove_rmap->set_page_dirty)
  *    bdi.wb->list_lock                (page_remove_rmap->set_page_dirty)
  *    ->inode->i_lock          (page_remove_rmap->set_page_dirty)
- *    ->memcg->move_lock       (page_remove_rmap->mem_cgroup_begin_page_stat)
+ *    ->memcg->move_lock       (page_remove_rmap->lock_page_memcg)
  *    bdi.wb->list_lock                (zap_pte_range->set_page_dirty)
  *    ->inode->i_lock          (zap_pte_range->set_page_dirty)
  *    ->private_lock           (zap_pte_range->__set_page_dirty_buffers)
@@ -176,11 +176,9 @@ static void page_cache_tree_delete(struct address_space *mapping,
 /*
  * Delete a page from the page cache and free it. Caller has to make
  * sure the page is locked and that nobody else uses it - or that usage
- * is safe.  The caller must hold the mapping's tree_lock and
- * mem_cgroup_begin_page_stat().
+ * is safe.  The caller must hold the mapping's tree_lock.
  */
-void __delete_from_page_cache(struct page *page, void *shadow,
-                             struct mem_cgroup *memcg)
+void __delete_from_page_cache(struct page *page, void *shadow)
 {
        struct address_space *mapping = page->mapping;
 
@@ -239,8 +237,7 @@ void __delete_from_page_cache(struct page *page, void *shadow,
         * anyway will be cleared before returning page into buddy allocator.
         */
        if (WARN_ON_ONCE(PageDirty(page)))
-               account_page_cleaned(page, mapping, memcg,
-                                    inode_to_wb(mapping->host));
+               account_page_cleaned(page, mapping, inode_to_wb(mapping->host));
 }
 
 /**
@@ -254,7 +251,6 @@ void __delete_from_page_cache(struct page *page, void *shadow,
 void delete_from_page_cache(struct page *page)
 {
        struct address_space *mapping = page->mapping;
-       struct mem_cgroup *memcg;
        unsigned long flags;
 
        void (*freepage)(struct page *);
@@ -263,11 +259,9 @@ void delete_from_page_cache(struct page *page)
 
        freepage = mapping->a_ops->freepage;
 
-       memcg = mem_cgroup_begin_page_stat(page);
        spin_lock_irqsave(&mapping->tree_lock, flags);
-       __delete_from_page_cache(page, NULL, memcg);
+       __delete_from_page_cache(page, NULL);
        spin_unlock_irqrestore(&mapping->tree_lock, flags);
-       mem_cgroup_end_page_stat(memcg);
 
        if (freepage)
                freepage(page);
@@ -551,7 +545,6 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
        if (!error) {
                struct address_space *mapping = old->mapping;
                void (*freepage)(struct page *);
-               struct mem_cgroup *memcg;
                unsigned long flags;
 
                pgoff_t offset = old->index;
@@ -561,9 +554,8 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
                new->mapping = mapping;
                new->index = offset;
 
-               memcg = mem_cgroup_begin_page_stat(old);
                spin_lock_irqsave(&mapping->tree_lock, flags);
-               __delete_from_page_cache(old, NULL, memcg);
+               __delete_from_page_cache(old, NULL);
                error = radix_tree_insert(&mapping->page_tree, offset, new);
                BUG_ON(error);
                mapping->nrpages++;
@@ -576,8 +568,7 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
                if (PageSwapBacked(new))
                        __inc_zone_page_state(new, NR_SHMEM);
                spin_unlock_irqrestore(&mapping->tree_lock, flags);
-               mem_cgroup_end_page_stat(memcg);
-               mem_cgroup_replace_page(old, new);
+               mem_cgroup_migrate(old, new);
                radix_tree_preload_end();
                if (freepage)
                        freepage(old);
@@ -595,7 +586,7 @@ static int page_cache_tree_insert(struct address_space *mapping,
        void **slot;
        int error;
 
-       error = __radix_tree_create(&mapping->page_tree, page->index,
+       error = __radix_tree_create(&mapping->page_tree, page->index, 0,
                                    &node, &slot);
        if (error)
                return error;
@@ -1264,7 +1255,6 @@ unsigned find_get_entries(struct address_space *mapping,
                return 0;
 
        rcu_read_lock();
-restart:
        radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) {
                struct page *page;
 repeat:
@@ -1272,8 +1262,10 @@ repeat:
                if (unlikely(!page))
                        continue;
                if (radix_tree_exception(page)) {
-                       if (radix_tree_deref_retry(page))
-                               goto restart;
+                       if (radix_tree_deref_retry(page)) {
+                               slot = radix_tree_iter_retry(&iter);
+                               continue;
+                       }
                        /*
                         * A shadow entry of a recently evicted page, a swap
                         * entry from shmem/tmpfs or a DAX entry.  Return it
@@ -1326,7 +1318,6 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start,
                return 0;
 
        rcu_read_lock();
-restart:
        radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) {
                struct page *page;
 repeat:
@@ -1336,13 +1327,8 @@ repeat:
 
                if (radix_tree_exception(page)) {
                        if (radix_tree_deref_retry(page)) {
-                               /*
-                                * Transient condition which can only trigger
-                                * when entry at index 0 moves out of or back
-                                * to root: none yet gotten, safe to restart.
-                                */
-                               WARN_ON(iter.index);
-                               goto restart;
+                               slot = radix_tree_iter_retry(&iter);
+                               continue;
                        }
                        /*
                         * A shadow entry of a recently evicted page,
@@ -1393,7 +1379,6 @@ unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index,
                return 0;
 
        rcu_read_lock();
-restart:
        radix_tree_for_each_contig(slot, &mapping->page_tree, &iter, index) {
                struct page *page;
 repeat:
@@ -1404,12 +1389,8 @@ repeat:
 
                if (radix_tree_exception(page)) {
                        if (radix_tree_deref_retry(page)) {
-                               /*
-                                * Transient condition which can only trigger
-                                * when entry at index 0 moves out of or back
-                                * to root: none yet gotten, safe to restart.
-                                */
-                               goto restart;
+                               slot = radix_tree_iter_retry(&iter);
+                               continue;
                        }
                        /*
                         * A shadow entry of a recently evicted page,
@@ -1469,7 +1450,6 @@ unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index,
                return 0;
 
        rcu_read_lock();
-restart:
        radix_tree_for_each_tagged(slot, &mapping->page_tree,
                                   &iter, *index, tag) {
                struct page *page;
@@ -1480,12 +1460,8 @@ repeat:
 
                if (radix_tree_exception(page)) {
                        if (radix_tree_deref_retry(page)) {
-                               /*
-                                * Transient condition which can only trigger
-                                * when entry at index 0 moves out of or back
-                                * to root: none yet gotten, safe to restart.
-                                */
-                               goto restart;
+                               slot = radix_tree_iter_retry(&iter);
+                               continue;
                        }
                        /*
                         * A shadow entry of a recently evicted page.
@@ -1548,7 +1524,6 @@ unsigned find_get_entries_tag(struct address_space *mapping, pgoff_t start,
                return 0;
 
        rcu_read_lock();
-restart:
        radix_tree_for_each_tagged(slot, &mapping->page_tree,
                                   &iter, start, tag) {
                struct page *page;
@@ -1558,12 +1533,8 @@ repeat:
                        continue;
                if (radix_tree_exception(page)) {
                        if (radix_tree_deref_retry(page)) {
-                               /*
-                                * Transient condition which can only trigger
-                                * when entry at index 0 moves out of or back
-                                * to root: none yet gotten, safe to restart.
-                                */
-                               goto restart;
+                               slot = radix_tree_iter_retry(&iter);
+                               continue;
                        }
 
                        /*
@@ -1869,15 +1840,16 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
        ssize_t retval = 0;
        loff_t *ppos = &iocb->ki_pos;
        loff_t pos = *ppos;
+       size_t count = iov_iter_count(iter);
+
+       if (!count)
+               goto out; /* skip atime */
 
        if (iocb->ki_flags & IOCB_DIRECT) {
                struct address_space *mapping = file->f_mapping;
                struct inode *inode = mapping->host;
-               size_t count = iov_iter_count(iter);
                loff_t size;
 
-               if (!count)
-                       goto out; /* skip atime */
                size = i_size_read(inode);
                retval = filemap_write_and_wait_range(mapping, pos,
                                        pos + count - 1);
@@ -2180,10 +2152,11 @@ repeat:
                if (unlikely(!page))
                        goto next;
                if (radix_tree_exception(page)) {
-                       if (radix_tree_deref_retry(page))
-                               break;
-                       else
-                               goto next;
+                       if (radix_tree_deref_retry(page)) {
+                               slot = radix_tree_iter_retry(&iter);
+                               continue;
+                       }
+                       goto next;
                }
 
                if (!page_cache_get_speculative(page))