libceph: do crc calculations outside loop

Move blocks of code out of loops in read_partial_message_section()
and read_partial_message().  They were only was getting called at
the end of the last iteration of the loop anyway.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 7ec6a228b6676ff9dd28922209f0a83551a64da3..575511a29eb7f68d7526d8d74119680caaa61751 100644 (file)
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -1544,10 +1544,9 @@ static int read_partial_message_section(struct ceph_connection *con,
                if (ret <= 0)
                        return ret;
                section->iov_len += ret;
-               if (section->iov_len == sec_len)
-                       *crc = crc32c(0, section->iov_base,
-                                     section->iov_len);
        }
+       if (section->iov_len == sec_len)
+               *crc = crc32c(0, section->iov_base, section->iov_len);
 
        return 1;
 }
@@ -1638,6 +1637,7 @@ static int read_partial_message(struct ceph_connection *con)
        bool do_datacrc = con->msgr->nocrc;
        int skip;
        u64 seq;
+       u32 crc;
 
        dout("read_partial_message con %p msg %p\n", con, m);
 
@@ -1650,18 +1650,16 @@ static int read_partial_message(struct ceph_connection *con)
                if (ret <= 0)
                        return ret;
                con->in_base_pos += ret;
-               if (con->in_base_pos == sizeof(con->in_hdr)) {
-                       u32 crc = crc32c(0, &con->in_hdr,
-                                       offsetof(struct ceph_msg_header, crc));
-
-                       if (cpu_to_le32(crc) != con->in_hdr.crc) {
-                               pr_err("read_partial_message bad hdr "
-                                      " crc %u != expected %u\n",
-                                      crc, con->in_hdr.crc);
-                               return -EBADMSG;
-                       }
-               }
        }
+
+       crc = crc32c(0, &con->in_hdr, offsetof(struct ceph_msg_header, crc));
+       if (cpu_to_le32(crc) != con->in_hdr.crc) {
+               pr_err("read_partial_message bad hdr "
+                      " crc %u != expected %u\n",
+                      crc, con->in_hdr.crc);
+               return -EBADMSG;
+       }
+
        front_len = le32_to_cpu(con->in_hdr.front_len);
        if (front_len > CEPH_MSG_MAX_FRONT_LEN)
                return -EIO;