fully save/restore scheduler parameters

(This used to be ctdb commit 59408eabe7515d49a6eef3b6fb2590a1cd1df956)

diff --git a/ctdb/common/ctdb_util.c b/ctdb/common/ctdb_util.c
index f8f7cb5150a293c5817bedd58fa1227b1b0074d6..4890a141ea73031a58420aa537d115b5eff4a06f 100644 (file)
--- a/ctdb/common/ctdb_util.c
+++ b/ctdb/common/ctdb_util.c
@@ -192,20 +192,42 @@ struct ctdb_rec_data *ctdb_marshall_record(TALLOC_CTX *mem_ctx, uint32_t reqid,
 /*
   if possible, make this task real time
  */
-void ctdb_set_realtime(bool enable)
+void ctdb_set_scheduler(struct ctdb_context *ctdb)
 {
-#if HAVE_SCHED_SETSCHEDULER
+#if HAVE_SCHED_SETSCHEDULER    
        struct sched_param p;
-       p.__sched_priority = 1;
-
-       if (enable) {
-               if (sched_setscheduler(getpid(), SCHED_FIFO, &p) == -1) {
-                       DEBUG(0,("Unable to set scheduler to SCHED_FIFO (%s)\n", strerror(errno)));
-               } else {
-                       DEBUG(0,("Set scheduler to SCHED_FIFO\n"));
-               }
+
+       if (ctdb->saved_scheduler_param == NULL) {
+               ctdb->saved_scheduler_param = talloc_size(ctdb, sizeof(p));
+       }
+       
+       if (sched_getparam(0, (struct sched_param *)ctdb->saved_scheduler_param) == -1) {
+               DEBUG(0,("Unable to get old scheduler params\n"));
+               return;
+       }
+
+       p = *(struct sched_param *)ctdb->saved_scheduler_param;
+       p.sched_priority = 1;
+
+       if (sched_setscheduler(0, SCHED_FIFO, &p) == -1) {
+               DEBUG(0,("Unable to set scheduler to SCHED_FIFO (%s)\n", strerror(errno)));
        } else {
-               sched_setscheduler(getpid(), SCHED_OTHER, &p);
+               DEBUG(0,("Set scheduler to SCHED_FIFO\n"));
+       }
+#endif
+}
+
+/*
+  restore previous scheduler parameters
+ */
+void ctdb_restore_scheduler(struct ctdb_context *ctdb)
+{
+#if HAVE_SCHED_SETSCHEDULER    
+       if (ctdb->saved_scheduler_param == NULL) {
+               ctdb_fatal(ctdb, "No saved scheduler parameters\n");
+       }
+       if (sched_setscheduler(0, SCHED_OTHER, (struct sched_param *)ctdb->saved_scheduler_param) == -1) {
+               ctdb_fatal(ctdb, "Unable to restore old scheduler parameters\n");
        }
 #endif
 }

diff --git a/ctdb/include/ctdb_private.h b/ctdb/include/ctdb_private.h
index b584794f1c9e14ec74a466b09e70e2c4a0192e39..be3b832832a6b008501fec9528ef059613553171 100644 (file)
--- a/ctdb/include/ctdb_private.h
+++ b/ctdb/include/ctdb_private.h
@@ -308,6 +308,7 @@ struct ctdb_context {
        struct ctdb_tcp_list *tcp_list;
        struct ctdb_client_ip *client_ip_list;
        bool do_setsched;
+       void *saved_scheduler_param;
 };
 
 struct ctdb_db_context {
@@ -948,7 +949,8 @@ int ctdb_ctrl_set_rsn_nonempty(struct ctdb_context *ctdb, struct timeval timeout
                               uint32_t destnode, uint32_t db_id, uint64_t rsn);
 int ctdb_ctrl_delete_low_rsn(struct ctdb_context *ctdb, struct timeval timeout, 
                             uint32_t destnode, uint32_t db_id, uint64_t rsn);
-void ctdb_set_realtime(bool enable);
+void ctdb_set_scheduler(struct ctdb_context *ctdb);
+void ctdb_restore_scheduler(struct ctdb_context *ctdb);
 int32_t ctdb_control_takeover_ip(struct ctdb_context *ctdb, 
                                 struct ctdb_req_control *c,
                                 TDB_DATA indata, 

diff --git a/ctdb/server/ctdb_daemon.c b/ctdb/server/ctdb_daemon.c
index ce84db3e685f0380ea783324abb47f3f97d879dd..546c7fca01980d7a6d6a1d4fb4d1cba03a21ad36 100644 (file)
--- a/ctdb/server/ctdb_daemon.c
+++ b/ctdb/server/ctdb_daemon.c
@@ -646,7 +646,7 @@ int ctdb_start_daemon(struct ctdb_context *ctdb, bool do_fork)
 
        if (ctdb->do_setsched) {
                /* try to set us up as realtime */
-               ctdb_set_realtime(true);
+               ctdb_set_scheduler(ctdb);
        }
 
        /* ensure the socket is deleted on exit of the daemon */

diff --git a/ctdb/server/eventscript.c b/ctdb/server/eventscript.c
index fab9175ed290a8bbe535789ab84a6e5be89ea708..f40cda18bdb7d5e303fe6ea111313aea6e0aad56 100644 (file)
--- a/ctdb/server/eventscript.c
+++ b/ctdb/server/eventscript.c
@@ -167,7 +167,7 @@ int ctdb_event_script_callback(struct ctdb_context *ctdb,
        if (state->child == 0) {
                close(state->fd[0]);
                if (ctdb->do_setsched) {
-                       ctdb_set_realtime(false);
+                       ctdb_restore_scheduler(ctdb);
                }
                set_close_on_exec(state->fd[1]);
                va_start(ap, fmt);