[PATCH 2/5] netfs: Call trace_netfs_read() after ->begin_cache_operation()

[David Howells]

Reorder the netfs library API functions slightly to log the netfs_read
tracepoint after calling out to the network filesystem to begin a caching
operation.  This sets rreq->cookie_debug_id so that it can be logged in
tracepoints.

Signed-off-by: David Howells <dhowe...@redhat.com>
---

 fs/netfs/read_helper.c |   23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/fs/netfs/read_helper.c b/fs/netfs/read_helper.c
index 0066db21aa11..8040b76da1b6 100644
--- a/fs/netfs/read_helper.c
+++ b/fs/netfs/read_helper.c
@@ -890,15 +890,16 @@ void netfs_readahead(struct readahead_control *ractl,
        rreq->start     = readahead_pos(ractl);
        rreq->len       = readahead_length(ractl);
 
-       netfs_stat(&netfs_n_rh_readahead);
-       trace_netfs_read(rreq, readahead_pos(ractl), readahead_length(ractl),
-                        netfs_read_trace_readahead);
-
        if (ops->begin_cache_operation) {
                ret = ops->begin_cache_operation(rreq);
                if (ret == -ENOMEM || ret == -EINTR || ret == -ERESTARTSYS)
                        goto cleanup_free;
        }
+
+       netfs_stat(&netfs_n_rh_readahead);
+       trace_netfs_read(rreq, readahead_pos(ractl), readahead_length(ractl),
+                        netfs_read_trace_readahead);
+
        netfs_rreq_expand(rreq, ractl);
 
        atomic_set(&rreq->nr_rd_ops, 1);
@@ -968,9 +969,6 @@ int netfs_readpage(struct file *file,
        rreq->start     = page_index(page) * PAGE_SIZE;
        rreq->len       = thp_size(page);
 
-       netfs_stat(&netfs_n_rh_readpage);
-       trace_netfs_read(rreq, rreq->start, rreq->len, 
netfs_read_trace_readpage);
-
        if (ops->begin_cache_operation) {
                ret = ops->begin_cache_operation(rreq);
                if (ret == -ENOMEM || ret == -EINTR || ret == -ERESTARTSYS) {
@@ -979,6 +977,9 @@ int netfs_readpage(struct file *file,
                }
        }
 
+       netfs_stat(&netfs_n_rh_readpage);
+       trace_netfs_read(rreq, rreq->start, rreq->len, 
netfs_read_trace_readpage);
+
        netfs_get_read_request(rreq);
 
        atomic_set(&rreq->nr_rd_ops, 1);
@@ -1111,15 +1112,15 @@ int netfs_write_begin(struct file *file, struct 
address_space *mapping,
        __set_bit(NETFS_RREQ_NO_UNLOCK_PAGE, &rreq->flags);
        netfs_priv = NULL;
 
-       netfs_stat(&netfs_n_rh_write_begin);
-       trace_netfs_read(rreq, pos, len, netfs_read_trace_write_begin);
-
        if (ops->begin_cache_operation) {
                ret = ops->begin_cache_operation(rreq);
                if (ret == -ENOMEM || ret == -EINTR || ret == -ERESTARTSYS)
-                       goto error;
+                       goto error_put;
        }
 
+       netfs_stat(&netfs_n_rh_write_begin);
+       trace_netfs_read(rreq, pos, len, netfs_read_trace_write_begin);
+
        /* Expand the request to meet caching requirements and download
         * preferences.
         */