[PATCH] fix weird logic in alloc_fdtable()

There's a fairly obvious infinite loop in there.

Also, use roundup_pow_of_two() rather than open-coding stuff.

Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/file.c b/fs/file.c
index 55f4e70225631b275f85215ee543b104507caacc..3f356086061d7076a379b76e265295a5fe3750fe 100644 (file)
--- a/fs/file.c
+++ b/fs/file.c
@@ -240,13 +240,9 @@ static struct fdtable *alloc_fdtable(int nr)
        if (!fdt)
                goto out;
 
-       nfds = 8 * L1_CACHE_BYTES;
-       /* Expand to the max in easy steps */
-       while (nfds <= nr) {
-               nfds = nfds * 2;
-               if (nfds > NR_OPEN)
-                       nfds = NR_OPEN;
-       }
+       nfds = max_t(int, 8 * L1_CACHE_BYTES, roundup_pow_of_two(nfds));
+       if (nfds > NR_OPEN)
+               nfds = NR_OPEN;
 
        new_openset = alloc_fdset(nfds);
        new_execset = alloc_fdset(nfds);