Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 44 insertions, 26 deletions

diff --git a/mm/rmap.c b/mm/rmap.c
index c8454e0..5b5ad58 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -120,6 +120,21 @@ static void anon_vma_chain_free(struct anon_vma_chain *anon_vma_chain)
 	kmem_cache_free(anon_vma_chain_cachep, anon_vma_chain);
 }
 
+static void anon_vma_chain_link(struct vm_area_struct *vma,
+				struct anon_vma_chain *avc,
+				struct anon_vma *anon_vma)
+{
+	avc->vma = vma;
+	avc->anon_vma = anon_vma;
+	list_add(&avc->same_vma, &vma->anon_vma_chain);
+
+	/*
+	 * It's critical to add new vmas to the tail of the anon_vma,
+	 * see comment in huge_memory.c:__split_huge_page().
+	 */
+	list_add_tail(&avc->same_anon_vma, &anon_vma->head);
+}
+
 /**
  * anon_vma_prepare - attach an anon_vma to a memory region
  * @vma: the memory region in question
@@ -175,10 +190,7 @@ int anon_vma_prepare(struct vm_area_struct *vma)
 		spin_lock(&mm->page_table_lock);
 		if (likely(!vma->anon_vma)) {
 			vma->anon_vma = anon_vma;
-			avc->anon_vma = anon_vma;
-			avc->vma = vma;
-			list_add(&avc->same_vma, &vma->anon_vma_chain);
-			list_add_tail(&avc->same_anon_vma, &anon_vma->head);
+			anon_vma_chain_link(vma, avc, anon_vma);
 			allocated = NULL;
 			avc = NULL;
 		}
@@ -224,21 +236,6 @@ static inline void unlock_anon_vma_root(struct anon_vma *root)
 		mutex_unlock(&root->mutex);
 }
 
-static void anon_vma_chain_link(struct vm_area_struct *vma,
-				struct anon_vma_chain *avc,
-				struct anon_vma *anon_vma)
-{
-	avc->vma = vma;
-	avc->anon_vma = anon_vma;
-	list_add(&avc->same_vma, &vma->anon_vma_chain);
-
-	/*
-	 * It's critical to add new vmas to the tail of the anon_vma,
-	 * see comment in huge_memory.c:__split_huge_page().
-	 */
-	list_add_tail(&avc->same_anon_vma, &anon_vma->head);
-}
-
 /*
  * Attach the anon_vmas from src to dst.
  * Returns 0 on success, -ENOMEM on failure.
@@ -1151,10 +1148,15 @@ void page_add_new_anon_rmap(struct page *page,
  */
 void page_add_file_rmap(struct page *page)
 {
+	bool locked;
+	unsigned long flags;
+
+	mem_cgroup_begin_update_page_stat(page, &locked, &flags);
 	if (atomic_inc_and_test(&page->_mapcount)) {
 		__inc_zone_page_state(page, NR_FILE_MAPPED);
 		mem_cgroup_inc_page_stat(page, MEMCG_NR_FILE_MAPPED);
 	}
+	mem_cgroup_end_update_page_stat(page, &locked, &flags);
 }
 
 /**
@@ -1165,9 +1167,21 @@ void page_add_file_rmap(struct page *page)
  */
 void page_remove_rmap(struct page *page)
 {
+	bool anon = PageAnon(page);
+	bool locked;
+	unsigned long flags;
+
+	/*
+	 * The anon case has no mem_cgroup page_stat to update; but may
+	 * uncharge_page() below, where the lock ordering can deadlock if
+	 * we hold the lock against page_stat move: so avoid it on anon.
+	 */
+	if (!anon)
+		mem_cgroup_begin_update_page_stat(page, &locked, &flags);
+
 	/* page still mapped by someone else? */
 	if (!atomic_add_negative(-1, &page->_mapcount))
-		return;
+		goto out;
 
 	/*
 	 * Now that the last pte has gone, s390 must transfer dirty
@@ -1176,7 +1190,7 @@ void page_remove_rmap(struct page *page)
 	 * not if it's in swapcache - there might be another pte slot
 	 * containing the swap entry, but page not yet written to swap.
 	 */
-	if ((!PageAnon(page) || PageSwapCache(page)) &&
+	if ((!anon || PageSwapCache(page)) &&
 	    page_test_and_clear_dirty(page_to_pfn(page), 1))
 		set_page_dirty(page);
 	/*
@@ -1184,8 +1198,8 @@ void page_remove_rmap(struct page *page)
 	 * and not charged by memcg for now.
 	 */
 	if (unlikely(PageHuge(page)))
-		return;
-	if (PageAnon(page)) {
+		goto out;
+	if (anon) {
 		mem_cgroup_uncharge_page(page);
 		if (!PageTransHuge(page))
 			__dec_zone_page_state(page, NR_ANON_PAGES);
@@ -1205,6 +1219,9 @@ void page_remove_rmap(struct page *page)
 	 * Leaving it set also helps swapoff to reinstate ptes
 	 * faster for those pages still in swapcache.
 	 */
+out:
+	if (!anon)
+		mem_cgroup_end_update_page_stat(page, &locked, &flags);
 }
 
 /*
@@ -1282,7 +1299,7 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 			}
 			dec_mm_counter(mm, MM_ANONPAGES);
 			inc_mm_counter(mm, MM_SWAPENTS);
-		} else if (PAGE_MIGRATION) {
+		} else if (IS_ENABLED(CONFIG_MIGRATION)) {
 			/*
 			 * Store the pfn of the page in a special migration
 			 * pte. do_swap_page() will wait until the migration
@@ -1293,7 +1310,8 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 		}
 		set_pte_at(mm, address, pte, swp_entry_to_pte(entry));
 		BUG_ON(pte_file(*pte));
-	} else if (PAGE_MIGRATION && (TTU_ACTION(flags) == TTU_MIGRATION)) {
+	} else if (IS_ENABLED(CONFIG_MIGRATION) &&
+		   (TTU_ACTION(flags) == TTU_MIGRATION)) {
 		/* Establish migration entry for a file page */
 		swp_entry_t entry;
 		entry = make_migration_entry(page, pte_write(pteval));
@@ -1499,7 +1517,7 @@ static int try_to_unmap_anon(struct page *page, enum ttu_flags flags)
 		 * locking requirements of exec(), migration skips
 		 * temporary VMAs until after exec() completes.
 		 */
-		if (PAGE_MIGRATION && (flags & TTU_MIGRATION) &&
+		if (IS_ENABLED(CONFIG_MIGRATION) && (flags & TTU_MIGRATION) &&
 				is_vma_temporary_stack(vma))
 			continue;