random: Adjust the number of loops when initializing

When we are initializing using arch_get_random_long() we only need to
loop enough times to touch all the bytes in the buffer; using
poolwords for that does twice the number of operations necessary on a
64-bit machine, since in the random number generator code "word" means
32 bits.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Link: http://lkml.kernel.org/r/1324589281-31931-1-git-send-email-tytso@mit.edu

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 3079477..9a2156d 100644 (file)
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -975,7 +975,7 @@ static void init_std_data(struct entropy_store *r)
 
        now = ktime_get_real();
        mix_pool_bytes(r, &now, sizeof(now));
-       for (i = r->poolinfo->poolwords; i; i--) {
+       for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof flags) {
                if (!arch_get_random_long(&flags))
                        break;
                mix_pool_bytes(r, &flags, sizeof(flags));