random: consolidate wakeup logic

Signed-off-by: Matt Mackall <mpm@selenic.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 16 deletions

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 32118598a71b..46944088cf94 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -540,6 +540,10 @@ static void credit_entropy_store(struct entropy_store *r, int nbits)
                                   nbits, r->name);
         }
 
+        /* should we wake readers? */
+        if (r == &input_pool && r->entropy_count >= random_read_wakeup_thresh)
+                wake_up_interruptible(&random_read_wait);
+
         spin_unlock_irqrestore(&r->lock, flags);
 }
 
@@ -624,10 +628,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
                 credit_entropy_store(&input_pool,
                                      min_t(int, fls(delta>>1), 11));
         }
-
-        if (input_pool.entropy_count >= random_read_wakeup_thresh)
-                wake_up_interruptible(&random_read_wait);
-
 out:
         preempt_enable();
 }
@@ -1081,12 +1081,6 @@ static int random_ioctl(struct inode *inode, struct file *file,
                 if (get_user(ent_count, p))
                         return -EFAULT;
                 credit_entropy_store(&input_pool, ent_count);
-                /*
-                 * Wake up waiting processes if we have enough
-                 * entropy.
-                 */
-                if (input_pool.entropy_count >= random_read_wakeup_thresh)
-                        wake_up_interruptible(&random_read_wait);
                 return 0;
         case RNDADDENTROPY:
                 if (!capable(CAP_SYS_ADMIN))
@@ -1102,12 +1096,6 @@ static int random_ioctl(struct inode *inode, struct file *file,
                 if (retval < 0)
                         return retval;
                 credit_entropy_store(&input_pool, ent_count);
-                /*
-                 * Wake up waiting processes if we have enough
-                 * entropy.
-                 */
-                if (input_pool.entropy_count >= random_read_wakeup_thresh)
-                        wake_up_interruptible(&random_read_wait);
                 return 0;
         case RNDZAPENTCNT:
         case RNDCLEARPOOL: