xprtrdma: Clean up fixup_copy_count accounting

fixup_copy_count should count only the number of bytes copied to the
page list. The head and tail are now always handled without a data
copy.

And the debugging at the end of rpcrdma_inline_fixup() is also no
longer necessary, since copy_len will be non-zero when there is reply
data in the tail (a normal and valid case).

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever 2016-06-29 13:54:58 -04:00 committed by Anna Schumaker
parent cfabe2c634
commit 64695bde6c

View file

@ -755,11 +755,14 @@ rpcrdma_count_chunks(struct rpcrdma_rep *rep, int wrchunk, __be32 **iptrp)
* many cases this function simply updates iov_base pointers in
* rq_rcv_buf to point directly to the received reply data, to
* avoid copying reply data.
*
* Returns the count of bytes which had to be memcopied.
*/
static void
static unsigned long
rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
{
int i, npages, curlen, olen;
unsigned long fixup_copy_count;
int i, npages, curlen;
char *destp;
struct page **ppages;
int page_base;
@ -781,13 +784,10 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
srcp += curlen;
copy_len -= curlen;
olen = copy_len;
i = 0;
rpcx_to_rdmax(rqst->rq_xprt)->rx_stats.fixup_copy_count += olen;
page_base = rqst->rq_rcv_buf.page_base;
ppages = rqst->rq_rcv_buf.pages + (page_base >> PAGE_SHIFT);
page_base &= ~PAGE_MASK;
fixup_copy_count = 0;
if (copy_len && rqst->rq_rcv_buf.page_len) {
int pagelist_len;
@ -795,7 +795,7 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
if (pagelist_len > copy_len)
pagelist_len = copy_len;
npages = PAGE_ALIGN(page_base + pagelist_len) >> PAGE_SHIFT;
for (; i < npages; i++) {
for (i = 0; i < npages; i++) {
curlen = PAGE_SIZE - page_base;
if (curlen > pagelist_len)
curlen = pagelist_len;
@ -809,6 +809,7 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
kunmap_atomic(destp);
srcp += curlen;
copy_len -= curlen;
fixup_copy_count += curlen;
pagelist_len -= curlen;
if (!pagelist_len)
break;
@ -833,10 +834,7 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
rqst->rq_private_buf.tail[0].iov_base = srcp;
}
if (copy_len)
dprintk("RPC: %s: %d bytes in"
" %d extra segments (%d lost)\n",
__func__, olen, i, copy_len);
return fixup_copy_count;
}
void
@ -999,8 +997,10 @@ rpcrdma_reply_handler(struct rpcrdma_rep *rep)
rep->rr_len -= RPCRDMA_HDRLEN_MIN;
status = rep->rr_len;
}
/* Fix up the rpc results for upper layer */
rpcrdma_inline_fixup(rqst, (char *)iptr, rep->rr_len, rdmalen);
r_xprt->rx_stats.fixup_copy_count +=
rpcrdma_inline_fixup(rqst, (char *)iptr, rep->rr_len,
rdmalen);
break;
case rdma_nomsg: