cluster/afr: Perform delayed changelog wakeups for anon fd

Problem:
Nfs xlator never does open on a file for performing writes,
afr does not perform changelog wakeup for this fd so operations
which do metadata operations as soon as the data operations are
completed perceive a delay of 'post-op-delay-secs'.

Fix:
Perform changelog wakeup on anon-fd if the fd with same pid is
not present in inode-list.

Note:
This approach is a short-term fix. A proper fix needs a new domain
for taking metadata locks so that data/metadata locks don't compete
with each other.

Change-Id: I253afb289eadf30c7951e56fb2c4840d7132f5e4
BUG: 966018
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/5066
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

2 files changed, 20 insertions, 0 deletions

diff --git a/libglusterfs/src/fd.c b/libglusterfs/src/fd.c
index 2f4afc5e87a..36cc4d0561f 100644
--- a/libglusterfs/src/fd.c
+++ b/libglusterfs/src/fd.c
@@ -780,6 +780,23 @@ fd_anonymous (inode_t *inode)
         return fd;
 }
 
+fd_t*
+fd_lookup_anonymous (inode_t *inode)
+{
+        fd_t *fd = NULL;
+
+        if (!inode) {
+                gf_log_callingfn ("fd", GF_LOG_WARNING, "!inode");
+                return NULL;
+        }
+
+        LOCK (&inode->lock);
+        {
+                fd = __fd_lookup_anonymous (inode);
+        }
+        UNLOCK (&inode->lock);
+        return fd;
+}
 
 gf_boolean_t
 fd_is_anonymous (fd_t *fd)
diff --git a/libglusterfs/src/fd.h b/libglusterfs/src/fd.h
index 54290b1980b..c1b9157d882 100644
--- a/libglusterfs/src/fd.h
+++ b/libglusterfs/src/fd.h
@@ -134,6 +134,9 @@ fd_lookup (struct _inode *inode, pid_t pid);
 fd_t *
 fd_lookup_uint64 (struct _inode *inode, uint64_t pid);
 
+fd_t*
+fd_lookup_anonymous (inode_t *inode);
+
 fd_t *
 fd_anonymous (inode_t *inode);