random: forget lock in lockless accounting
The only mutable data accessed here is ->entropy_count, but since
10b3a32d2 ("random: fix accounting race condition") we use cmpxchg to
protect our accesses to ->entropy_count here. Drop the use of the
lock.
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Price <price@mit.edu>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 9675821..694510af 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -970,9 +970,6 @@
int entropy_count, orig;
size_t ibytes;
- /* Hold lock while accounting */
- spin_lock_irqsave(&r->lock, flags);
-
BUG_ON(r->entropy_count > r->poolinfo->poolfracbits);
/* Can we pull enough? */
@@ -995,7 +992,6 @@
< random_write_wakeup_thresh)
wakeup_write = 1;
}
- spin_unlock_irqrestore(&r->lock, flags);
trace_debit_entropy(r->name, 8 * ibytes);
if (wakeup_write) {