mgmt/glusterd: Avoid re-starting nfs unconditionally.

NFS server is restarted unconditionally when a volume option is
configured through the set interface. This patch prevents restart
of NFS server when operations are performed on translators that
are not part of the NFS graph.

This does not prevent re-start of a NFS server when an option
corresponding to a translator that is part of the NFS graph is
re-configured.

Change-Id: Ic4b8e48e5e7e80438f230521042c267ec3b96a25
Signed-off-by: Vijay Bellur <vijay@gluster.com>
Reviewed-on: http://review.gluster.com/3247
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Raghavendra Bhat <raghavendrabhat@gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

4 files changed, 138 insertions, 1 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index 0f77350c181..8e28a7a1b3c 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -3181,6 +3181,28 @@ glusterd_reconfigure_shd ()
 }
 
 int
+glusterd_reconfigure_nfs ()
+{
+        int             ret             = -1;
+        gf_boolean_t    identical       = _gf_false;
+
+        ret = glusterd_check_nfs_volfile_identical (&identical);
+        if (ret)
+                goto out;
+
+        if (identical) {
+                ret = 0;
+                goto out;
+        }
+
+        ret = glusterd_check_generate_start_nfs ();
+
+out:
+        return ret;
+}
+
+
+int
 glusterd_check_generate_start_nfs ()
 {
         int ret = 0;
@@ -3304,7 +3326,7 @@ int
 glusterd_nodesvcs_handle_reconfigure (glusterd_volinfo_t *volinfo)
 {
         return glusterd_nodesvcs_batch_op (volinfo,
-                                           glusterd_check_generate_start_nfs,
+                                           glusterd_reconfigure_nfs,
                                            glusterd_reconfigure_shd);
 }
 
@@ -5459,3 +5481,60 @@ glusterd_defrag_volume_status_update (glusterd_volinfo_t *volinfo,
 
         return ret;
 }
+
+int
+glusterd_check_files_identical (char *filename1, char *filename2,
+                                gf_boolean_t *identical)
+{
+        int                     ret = -1;
+        struct stat             buf1 = {0,};
+        struct stat             buf2 = {0,};
+        uint32_t                cksum1 = 0;
+        uint32_t                cksum2 = 0;
+        xlator_t                *this = NULL;
+
+        GF_ASSERT (filename1);
+        GF_ASSERT (filename2);
+        GF_ASSERT (identical);
+
+        this = THIS;
+
+        ret = stat (filename1, &buf1);
+
+        if (ret) {
+                gf_log (this->name, GF_LOG_ERROR, "stat on file: %s failed "
+                        "(%s)", filename1, strerror (errno));
+                goto out;
+        }
+
+        ret = stat (filename2, &buf2);
+
+        if (ret) {
+                gf_log (this->name, GF_LOG_ERROR, "stat on file: %s failed "
+                        "(%s)", filename2, strerror (errno));
+                goto out;
+        }
+
+        if (buf1.st_size != buf2.st_size) {
+                *identical = _gf_false;
+                goto out;
+        }
+
+        ret = get_checksum_for_path (filename1, &cksum1);
+        if (ret)
+                goto out;
+
+
+        ret = get_checksum_for_path (filename2, &cksum2);
+        if (ret)
+                goto out;
+
+        if (cksum1 != cksum2)
+                *identical = _gf_false;
+        else
+                *identical = _gf_true;
+
+out:
+        gf_log (this->name, GF_LOG_DEBUG, "Returning with %d", ret);
+        return ret;
+}
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.h b/xlators/mgmt/glusterd/src/glusterd-utils.h
index 0213f0a1dfe..7b71f05a459 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.h
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.h
@@ -438,4 +438,8 @@ glusterd_validate_volume_id (dict_t *op_dict, glusterd_volinfo_t *volinfo);
 int
 glusterd_defrag_volume_status_update (glusterd_volinfo_t *volinfo,
                                       dict_t *rsp_dict);
+
+int
+glusterd_check_files_identical (char *filename1, char *filename2,
+                                gf_boolean_t *identical);
 #endif
diff --git a/xlators/mgmt/glusterd/src/glusterd-volgen.c b/xlators/mgmt/glusterd/src/glusterd-volgen.c
index 7639607dc53..043f6146b21 100644
--- a/xlators/mgmt/glusterd/src/glusterd-volgen.c
+++ b/xlators/mgmt/glusterd/src/glusterd-volgen.c
@@ -3345,6 +3345,58 @@ out:
 }
 
 int
+glusterd_check_nfs_volfile_identical (gf_boolean_t *identical)
+{
+        char            nfsvol[PATH_MAX]        = {0,};
+        char            tmpnfsvol[PATH_MAX]     = {0,};
+        glusterd_conf_t *conf                   = NULL;
+        xlator_t        *this                   = NULL;
+        int             ret                     = -1;
+        int             need_unlink             = 0;
+        int             tmp_fd                  = -1;
+
+        this = THIS;
+
+        GF_ASSERT (this);
+        GF_ASSERT (identical);
+
+        conf = this->private;
+
+        glusterd_get_nodesvc_volfile ("nfs", conf->workdir,
+                                      nfsvol, sizeof (nfsvol));
+
+        snprintf (tmpnfsvol, sizeof (tmpnfsvol), "/tmp/gnfs-XXXXXX");
+
+        tmp_fd = mkstemp (tmpnfsvol);
+        if (tmp_fd < 0) {
+                gf_log ("", GF_LOG_WARNING, "Unable to create temp file %s: "
+                                "(%s)", tmpnfsvol, strerror (errno));
+                goto out;
+        }
+
+        need_unlink = 1;
+
+        ret = glusterd_create_global_volfile (build_nfs_graph,
+                                              tmpnfsvol, NULL);
+        if (ret)
+                goto out;
+
+        ret = glusterd_check_files_identical (nfsvol, tmpnfsvol,
+                                              identical);
+        if (ret)
+                goto out;
+
+out:
+        if (need_unlink)
+                unlink (tmpnfsvol);
+
+        if (tmp_fd >= 0)
+                close (tmp_fd);
+
+        return ret;
+}
+
+int
 glusterd_delete_volfile (glusterd_volinfo_t *volinfo,
                          glusterd_brickinfo_t *brickinfo)
 {
diff --git a/xlators/mgmt/glusterd/src/glusterd-volgen.h b/xlators/mgmt/glusterd/src/glusterd-volgen.h
index feb1796c9bb..9e8370c9428 100644
--- a/xlators/mgmt/glusterd/src/glusterd-volgen.h
+++ b/xlators/mgmt/glusterd/src/glusterd-volgen.h
@@ -96,4 +96,6 @@ int generate_brick_volfiles (glusterd_volinfo_t *volinfo);
 int glusterd_get_volopt_content (gf_boolean_t xml_out);
 char*
 glusterd_get_trans_type_rb (gf_transport_type ttype);
+int
+glusterd_check_nfs_volfile_identical (gf_boolean_t *identical);
 #endif