2 files changed, 13 insertions, 6 deletions

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 61d63379e956..9c4ae6f14eea 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -400,16 +400,17 @@ extern struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
                                            struct vm_fault *vmf,
                                            struct vma_swap_readahead *swap_ra);
 
-static inline bool swap_use_vma_readahead(void)
-{
-        return READ_ONCE(swap_vma_readahead);
-}
-
 /* linux/mm/swapfile.c */
 extern atomic_long_t nr_swap_pages;
 extern long total_swap_pages;
+extern atomic_t nr_rotate_swap;
 extern bool has_usable_swap(void);
 
+static inline bool swap_use_vma_readahead(void)
+{
+        return READ_ONCE(swap_vma_readahead) && !atomic_read(&nr_rotate_swap);
+}
+
 /* Swap 50% full? Release swapcache more aggressively.. */
 static inline bool vm_swap_full(void)
 {
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 42eff9e4e972..4f8b3e08a547 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -96,6 +96,8 @@ static DECLARE_WAIT_QUEUE_HEAD(proc_poll_wait);
 /* Activity counter to indicate that a swapon or swapoff has occurred */
 static atomic_t proc_poll_event = ATOMIC_INIT(0);
 
+atomic_t nr_rotate_swap = ATOMIC_INIT(0);
+
 static inline unsigned char swap_count(unsigned char ent)
 {
         return ent & ~SWAP_HAS_CACHE;   /* may include SWAP_HAS_CONT flag */
@@ -2569,6 +2571,9 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
         if (p->flags & SWP_CONTINUED)
                 free_swap_count_continuations(p);
 
+        if (!p->bdev || !blk_queue_nonrot(bdev_get_queue(p->bdev)))
+                atomic_dec(&nr_rotate_swap);
+
         mutex_lock(&swapon_mutex);
         spin_lock(&swap_lock);
         spin_lock(&p->lock);
@@ -3145,7 +3150,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
                         cluster = per_cpu_ptr(p->percpu_cluster, cpu);
                         cluster_set_null(&cluster->index);
                 }
-        }
+        } else
+                atomic_inc(&nr_rotate_swap);
 
         error = swap_cgroup_swapon(p->type, maxpages);
         if (error)