tcp: suppress a division by zero warning

Andrew Morton reported following warning on one ARM build
with gcc-4.4 :

net/ipv4/inet_hashtables.c: In function 'inet_ehash_locks_alloc':
net/ipv4/inet_hashtables.c:617: warning: division by zero

Even guarded with a test on sizeof(spinlock_t), compiler does not
like current construct on a !CONFIG_SMP build.

Remove the warning by using a temporary variable.

Fixes: 095dc8e0c368 ("tcp: fix/cleanup inet_ehash_locks_alloc()")
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 5f9b063bbe8ab4f3755a5711ae19b816a3bc2026..0cb9165421d450ae8f6aff81b88ef4bf2839ff51 100644 (file)
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -624,22 +624,21 @@ EXPORT_SYMBOL_GPL(inet_hashinfo_init);
 
 int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
 {
+       unsigned int locksz = sizeof(spinlock_t);
        unsigned int i, nblocks = 1;
 
-       if (sizeof(spinlock_t) != 0) {
+       if (locksz != 0) {
                /* allocate 2 cache lines or at least one spinlock per cpu */
-               nblocks = max_t(unsigned int,
-                               2 * L1_CACHE_BYTES / sizeof(spinlock_t),
-                               1);
+               nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U);
                nblocks = roundup_pow_of_two(nblocks * num_possible_cpus());
 
                /* no more locks than number of hash buckets */
                nblocks = min(nblocks, hashinfo->ehash_mask + 1);
 
-               hashinfo->ehash_locks = kmalloc_array(nblocks, sizeof(spinlock_t),
+               hashinfo->ehash_locks = kmalloc_array(nblocks, locksz,
                                                      GFP_KERNEL | __GFP_NOWARN);
                if (!hashinfo->ehash_locks)
-                       hashinfo->ehash_locks = vmalloc(nblocks * sizeof(spinlock_t));
+                       hashinfo->ehash_locks = vmalloc(nblocks * locksz);
 
                if (!hashinfo->ehash_locks)
                        return -ENOMEM;