swapfile: swapon randomize if nonrot

[pandora-kernel.git] / mm / swapfile.c

diff --git a/mm/swapfile.c b/mm/swapfile.c
index ca75b9e..b0f5660 100644 (file)
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -16,6 +16,7 @@
 #include <linux/namei.h>
 #include <linux/shm.h>
 #include <linux/blkdev.h>
+#include <linux/random.h>
 #include <linux/writeback.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
@@ -1806,6 +1807,11 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
                goto bad_swap;
        }
 
+       if (blk_queue_nonrot(bdev_get_queue(p->bdev))) {
+               p->flags |= SWP_SOLIDSTATE;
+               srandom32((u32)get_seconds());
+               p->cluster_next = 1 + (random32() % p->highest_bit);
+       }
        if (discard_swap(p) == 0)
                p->flags |= SWP_DISCARDABLE;
 
@@ -1822,10 +1828,11 @@ asmlinkage long sys_swapon(const char __user * specialfile, int swap_flags)
        total_swap_pages += nr_good_pages;
 
        printk(KERN_INFO "Adding %uk swap on %s.  "
-                       "Priority:%d extents:%d across:%lluk%s\n",
+                       "Priority:%d extents:%d across:%lluk %s%s\n",
                nr_good_pages<<(PAGE_SHIFT-10), name, p->prio,
                nr_extents, (unsigned long long)span<<(PAGE_SHIFT-10),
-               (p->flags & SWP_DISCARDABLE) ? " D" : "");
+               (p->flags & SWP_SOLIDSTATE) ? "SS" : "",
+               (p->flags & SWP_DISCARDABLE) ? "D" : "");
 
        /* insert swap space into swap_list: */
        prev = -1;