added realtime initialization

git-svn-id: https://zerberus.eonerc.rwth-aachen.de:8443/svn/s2ss/trunk@48 8ec27952-4edc-4aab-86aa-e87bb2611832

Makefile

@@ -12,7 +12,7 @@ GIT_REV = $(shell git rev-parse --short HEAD)
 V ?= 4
 
 LDFLAGS = -pthread -lrt -lm -lconfig -lnl-3 -lnl-route-3
-CFLAGS = -g -std=c99 -Iinclude/ -D_XOPEN_SOURCE=500 -DV=$(V)
+CFLAGS = -g -std=c99 -Iinclude/ -D_XOPEN_SOURCE=500 -D_GNU_SOURCE -DV=$(V)
 CFLAGS += -D__GIT_REV__='"$(GIT_REV)"' -D__GIT_TAG__='"$(GIT_TAG)"'
 
 .PHONY: all clean doc

Readme

@@ -27,6 +27,7 @@ Contacts:
 
 	  - CAP_NET_ADMIN to increase the socket priority
 	  - CAP_SYS_NICE to set the realtime priority and cpu affinity
+	  - CAP_IPC_LOC to lock pages for better realtime
 
  3. Examples
 --------------------------------------------------------------------------------

etc/server.conf

@@ -2,11 +2,8 @@
 
 name = "s2ss";		# The name of this node
 
-# TODO: this has to be implmented
-# debug = 10;		# The debugging level (0 - 10)
-# affinity = 0xC0;	# Mask of cores the server should run on
-# nice = -20;		# Scheduler priority for the server
-# protocol = 0;		# Protocol version for UDP message format
+affinity = 0x02;	# Mask of cores the server should run on
+priority = 50;		# Scheduler priority for the server
 
 nodes = {
 	acs = {

include/cfg.h

@@ -10,8 +10,8 @@
 
 #include <libconfig.h>
 
-#include "path.h"
-#include "node.h"
+struct node;
+struct path;
 
 struct config {
 	/// Name of this node
@@ -21,7 +21,7 @@ struct config {
 	/// Verbosity level
 	int debug;
 	/// Task priority (lower is better)
-	int nice;
+	int priority;
 	/// Core affinity of this task
 	int affinity;
 	/// Protocol version of UDP packages

include/utils.h

@@ -13,7 +13,8 @@
 #include <errno.h>
 #include <string.h>
 
-#include <netinet/ip.h>
+struct config;
+struct sockaddr_in;
 
 enum log_level
 {
@@ -41,6 +42,18 @@ void print(enum log_level lvl, const char *fmt, ...);
  */
 int resolve(const char *addr, struct sockaddr_in *sa, int flags);
 
+/**
+ * @brief Setup various realtime realated things
+ *
+ *  - Prefault the stack
+ *  - Lock memory
+ *  - Use FIFO scheduler with realtime priority
+ *  - Set CPU affinity
+ *
+ * @param g The global configuration
+ */
+void realtime_init(struct config *g);
+
 /// Check assertion and exit if failed
 #define assert(exp) do { \
 	if (!(exp)) { \

src/cfg.c

@@ -11,6 +11,8 @@
 #include <stdlib.h>
 
 #include "cfg.h"
+#include "node.h"
+#include "path.h"
 #include "utils.h"
 
 int config_parse(config_t *cfg, struct config *g)
@@ -71,7 +73,7 @@ int config_parse_global(config_setting_t *c, struct config *g)
 
 	config_setting_lookup_int(c, "debug", &g->debug);
 	config_setting_lookup_int(c, "affinity", &g->affinity);
-	config_setting_lookup_int(c, "nice", &g->nice);
+	config_setting_lookup_int(c, "priority", &g->priority);
 	config_setting_lookup_int(c, "protocol", &g->protocol);
 
 	return CONFIG_TRUE;
@@ -96,8 +98,6 @@ int config_parse_path(config_setting_t *c, struct config *g)
 	if (!config_setting_lookup_string(c, "out", &out_str))
 		cerror(c, "Missing output node for path");
 
-	if (!config_setting_lookup_int)
-
 	info("Loading path from '%s' to '%s'", in_str, out_str);
 
 	in = node_lookup_name(in_str, g->nodes, g->node_count);

src/rt.c

@@ -1,50 +0,0 @@
-/**
- * Realtime related functions
- *
- * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
- * @copyright 2014, Institute for Automation of Complex Power Systems, EONERC
- */
-
-#include <string.h>
-#include <sched.h>
-
-#include "config.h"
-#include "utils.h"
-
-void rt_stack_prefault()
-{
-	unsigned char dummy[MAX_SAFE_STACK];
-
-	memset(dummy, 0, MAX_SAFE_STACK);
-	
-	
-}
-
-void rt_set_priority()
-{
-	struct sched_param param;
-
-	param.sched_priority = PRIORITY;
-        if (sched_setscheduler(0, SCHED_FIFO, &param) == -1) {
-                perror("sched_setscheduler failed");
-                exit(-1);
-        }
-}
-
-void rt_lock_memory()
-{
-	// TODO
-}
-
-void rt_set_affinity()
-{
-	// TODO
-}
-
-void rt_init()
-{
-	rt_set_priority();
-	rt_set_affinity();
-	rt_lock_memory();
-	rt_stack_prefault();
-}

src/server.c

@@ -90,16 +90,19 @@ int main(int argc, char *argv[])
 
 	info("This is s2ss %s", VERSION);
 
-	// Default settings
+	/* Default settings */
 	config.filename = argv[1];
 	config.debug = 0;
-	config.nice = 0;
+	config.priority = 0;
 	config.affinity = 0xC0;
 	config.protocol = 0;
 
 	config_init(&config.obj);
 	config_parse(&config.obj, &config);
 
+	/* Setup various realtime related things */
+	realtime_init(&config);
+
 	if (config.path_count)
 		info("Parsed %u nodes and %u paths", config.node_count, config.path_count);
 	else

src/utils.c

@@ -10,12 +10,19 @@
 #include <string.h>
 #include <time.h>
 #include <errno.h>
-
+#include <sched.h>
+#include <unistd.h>
 #include <netdb.h>
+#include <sched.h>
+
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 
 #include "config.h"
+#include "cfg.h"
 #include "utils.h"
 
 static const char *log_prefix[] = {
@@ -82,3 +89,39 @@ int resolve(const char *addr, struct sockaddr_in *sa, int flags)
 
 	return 0;
 }
+
+void realtime_init(struct config *g)
+{
+	/* Prefault stack */
+	char dummy[MAX_SAFE_STACK];
+	memset(dummy, 0, MAX_SAFE_STACK);
+
+	/* Lock memory */
+	if(mlockall(MCL_CURRENT | MCL_FUTURE))
+		perror("Failed mlockall");
+	else
+		debug(3, "Locked memory");
+
+	/* Check for realtime kernel patch */
+	struct stat st;
+	if (stat("/sys/kernel/realtime", &st))
+		warn("This is not a a realtime patched kernel");
+	else
+		debug(3 ,"This is a realtime patched kernel");
+
+	/* Use FIFO scheduler with realtime priority */
+	struct sched_param param;
+	param.sched_priority = g->priority;
+	if (sched_setscheduler(0, SCHED_FIFO, &param))
+		perror("Failed to set realtime priority");
+	else
+		debug(3, "Set task priority to %u", g->priority);
+
+	/* Pin threads to CPUs by setting the affinity */
+	size_t cset = g->affinity;
+	pid_t pid = getpid();
+	if (sched_setaffinity(pid, sizeof(cset), (const struct cpu_set_t *) &cset))
+		perror("Failed to set CPU affinity");
+	else
+		debug(3, "Set affinity to %#x", g->affinity);
+}