From a54e0358b1d66c04448b22c1a01e076b5a527008 Mon Sep 17 00:00:00 2001
From: Shehjar Tikoo <shehjart@gluster.com>
Date: Tue, 15 Mar 2011 01:57:13 +0000
Subject: nfs-rpc: Exit txbuf transmission loop on EAGAIN

..instead of looping till the buffer is completely transmitted.

Signed-off-by: Shehjar Tikoo <shehjart@gluster.com>
Signed-off-by: Vijay Bellur <vijay@dev.gluster.com>

BUG: 2491 ()
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2491
---
 xlators/nfs/lib/src/rpc-socket.c |  6 ++++--
 xlators/nfs/lib/src/rpc-socket.h |  2 +-
 xlators/nfs/lib/src/rpcsvc.c     | 17 ++++++++++++++---
 3 files changed, 19 insertions(+), 6 deletions(-)

(limited to 'xlators/nfs/lib/src')

diff --git a/xlators/nfs/lib/src/rpc-socket.c b/xlators/nfs/lib/src/rpc-socket.c
index 6c399d90416..ec56f3fc49e 100644
--- a/xlators/nfs/lib/src/rpc-socket.c
+++ b/xlators/nfs/lib/src/rpc-socket.c
@@ -226,7 +226,7 @@ nfs_rpcsvc_socket_read (int sockfd, char *readaddr, size_t readsize)
 
 
 ssize_t
-nfs_rpcsvc_socket_write (int sockfd, char *buffer, size_t size)
+nfs_rpcsvc_socket_write (int sockfd, char *buffer, size_t size, int *eagain)
 {
         size_t          writelen = -1;
         ssize_t         written = 0;
@@ -240,8 +240,10 @@ nfs_rpcsvc_socket_write (int sockfd, char *buffer, size_t size)
                         if (errno != EAGAIN) {
                                 written = -1;
                                 break;
-                        } else
+                        } else {
+                                *eagain = 1;
                                 break;
+                        }
                 } else if (writelen == 0)
                         break;
 
diff --git a/xlators/nfs/lib/src/rpc-socket.h b/xlators/nfs/lib/src/rpc-socket.h
index 0f91729774f..8662df0a741 100644
--- a/xlators/nfs/lib/src/rpc-socket.h
+++ b/xlators/nfs/lib/src/rpc-socket.h
@@ -49,7 +49,7 @@ extern ssize_t
 nfs_rpcsvc_socket_read (int sockfd, char *readaddr, size_t readsize);
 
 extern ssize_t
-nfs_rpcsvc_socket_write (int sockfd, char *buffer, size_t size);
+nfs_rpcsvc_socket_write (int sockfd, char *buffer, size_t size, int *eagain);
 
 extern int
 nfs_rpcsvc_socket_peername (int sockfd, char *hostname, int hostlen);
diff --git a/xlators/nfs/lib/src/rpcsvc.c b/xlators/nfs/lib/src/rpcsvc.c
index 363b94fbe13..3f6e3b9f0ea 100644
--- a/xlators/nfs/lib/src/rpcsvc.c
+++ b/xlators/nfs/lib/src/rpcsvc.c
@@ -2555,6 +2555,7 @@ __nfs_rpcsvc_conn_data_poll_out (rpcsvc_conn_t *conn)
         ssize_t                 written = -1;
         char                    *writeaddr = NULL;
         size_t                  writesize = -1;
+        int                     eagain = 0;
 
         if (!conn)
                 return -1;
@@ -2562,6 +2563,7 @@ __nfs_rpcsvc_conn_data_poll_out (rpcsvc_conn_t *conn)
         /* Attempt transmission of each of the pending buffers */
         list_for_each_entry_safe (txbuf, tmp, &conn->txbufs, txlist) {
 tx_remaining:
+                eagain = 0;
                 writeaddr = (char *)(txbuf->buf.iov_base + txbuf->offset);
                 writesize = (txbuf->buf.iov_len - txbuf->offset);
 
@@ -2571,7 +2573,7 @@ tx_remaining:
                 }
 
                 written = nfs_rpcsvc_socket_write (conn->sockfd, writeaddr,
-                                                   writesize);
+                                                   writesize, &eagain);
                 if (txbuf->txbehave & RPCSVC_TXB_LAST) {
                         gf_log (GF_RPCSVC, GF_LOG_TRACE, "Last Tx Buf");
                         nfs_rpcsvc_socket_unblock_tx (conn->sockfd);
@@ -2600,12 +2602,21 @@ tx_remaining:
 
                         list_del (&txbuf->txlist);
                         mem_put (conn->txpool, txbuf);
-                } else
+                } else {
                         /* If the current buffer is incompletely tx'd, do not
                          * go to the head of the loop, since that moves us to
                          * the next buffer.
+                         *
+                         * BUT, if the current transmission exited due to EAGAIN
+                         * we need to leave the buffers where they are and come
+                         * back later for retransmission.
                          */
-                        goto tx_remaining;
+                        if (!eagain)
+                                goto tx_remaining;
+                        else
+                                break;
+                }
+
         }
 
         /* If we've broken out of the loop above then we must unblock
-- 
cgit