From 50d4fb781287b47c4c2d455e3395783c1f06a3a5 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 24 Oct 2017 08:22:18 -0700 Subject: mm: Eliminate cond_resched_rcu_qs() in favor of cond_resched() Now that cond_resched() also provides RCU quiescent states when needed, it can be used in place of cond_resched_rcu_qs(). This commit therefore makes this change. Signed-off-by: Paul E. McKenney Cc: Andrew Morton Cc: "Kirill A. Shutemov" Cc: Vlastimil Babka --- mm/mlock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm') diff --git a/mm/mlock.c b/mm/mlock.c index 30472d438794..f7f54fd2e13f 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -779,7 +779,7 @@ static int apply_mlockall_flags(int flags) /* Ignore errors */ mlock_fixup(vma, &prev, vma->vm_start, vma->vm_end, newflags); - cond_resched_rcu_qs(); + cond_resched(); } out: return 0; -- cgit v1.2.3 From 08df477434754629303c9e2bfa8d67ecb44f9c20 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 9 Oct 2017 11:51:45 -0700 Subject: mm/ksm: Remove now-redundant smp_read_barrier_depends() Because READ_ONCE() now implies smp_read_barrier_depends(), the smp_read_barrier_depends() in get_ksm_page() is now redundant. This commit removes it and updates the comments. Signed-off-by: Paul E. McKenney Cc: Andrew Morton Cc: Andrea Arcangeli Cc: Minchan Kim Cc: Michal Hocko Cc: "Kirill A. Shutemov" Cc: Ingo Molnar Cc: "Aneesh Kumar K.V" Cc: Claudio Imbrenda Cc: --- mm/ksm.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) (limited to 'mm') diff --git a/mm/ksm.c b/mm/ksm.c index be8f4576f842..c406f75957ad 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -675,15 +675,8 @@ static struct page *get_ksm_page(struct stable_node *stable_node, bool lock_it) expected_mapping = (void *)((unsigned long)stable_node | PAGE_MAPPING_KSM); again: - kpfn = READ_ONCE(stable_node->kpfn); + kpfn = READ_ONCE(stable_node->kpfn); /* Address dependency. */ page = pfn_to_page(kpfn); - - /* - * page is computed from kpfn, so on most architectures reading - * page->mapping is naturally ordered after reading node->kpfn, - * but on Alpha we need to be more careful. - */ - smp_read_barrier_depends(); if (READ_ONCE(page->mapping) != expected_mapping) goto stale; -- cgit v1.2.3