sysinfo: support basic entries

Change-Id: I27f3e55058cc29f895831a1dddfafbc8585746a5
refs: #1389

kernel/include/rusage_private.h

@@ -56,6 +56,24 @@ rusage_total_memory_add(unsigned long size)
 #endif
 }
 
+static inline unsigned long
+rusage_get_total_memory()
+{
+	return rusage.total_memory;
+}
+
+static inline unsigned long
+rusage_get_free_memory()
+{
+	return rusage.total_memory - rusage.total_memory_usage;
+}
+
+static inline unsigned long
+rusage_get_usage_memory()
+{
+	return rusage.total_memory_usage;
+}
+
 static inline void
 rusage_rss_add(unsigned long size)
 {
@@ -399,6 +417,24 @@ rusage_rss_add(unsigned long size)
 {
 }
 
+static inline unsigned long
+rusage_get_total_memory()
+{
+	return 0;
+}
+
+static inline unsigned long
+rusage_get_free_memory()
+{
+	return 0;
+}
+
+static inline unsigned long
+rusage_get_usage_memory()
+{
+	return 0;
+}
+
 static inline void
 rusage_rss_sub(unsigned long size)
 {

kernel/include/syscall.h

@@ -443,6 +443,22 @@ struct rusage {
 	long   ru_nivcsw;
 };
 
+struct sysinfo {
+	long uptime;             /* Seconds since boot */
+	unsigned long loads[3];  /* 1, 5, and 15 minute load averages */
+	unsigned long totalram;  /* Total usable main memory size */
+	unsigned long freeram;   /* Available memory size */
+	unsigned long sharedram; /* Amount of shared memory */
+	unsigned long bufferram; /* Memory used by buffers */
+	unsigned long totalswap; /* Total swap space size */
+	unsigned long freeswap;  /* swap space still available */
+	unsigned short procs;    /* Number of current processes */
+	unsigned long totalhigh; /* Total high memory size */
+	unsigned long freehigh;  /* Available high memory size */
+	unsigned int mem_unit;   /* Memory unit size in bytes */
+	char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding for libc5 */
+};
+
 extern void terminate(int, int);
 
 struct tod_data_s {

kernel/syscall.c

@@ -6708,6 +6708,27 @@ SYSCALL_DECLARE(getrusage)
 	return 0;
 }
 
+SYSCALL_DECLARE(sysinfo)
+{
+	struct sysinfo *sysinfo = (struct sysinfo *)ihk_mc_syscall_arg0(ctx);
+	struct sysinfo __sysinfo;
+	int ret = 0;
+
+	memset(&__sysinfo, '\0', sizeof(struct sysinfo));
+
+	__sysinfo.totalram = rusage_get_total_memory();
+	__sysinfo.freeram = rusage_get_free_memory();
+	__sysinfo.mem_unit = 1; // always one unit for McKernel
+
+	if (copy_to_user(sysinfo, &__sysinfo, sizeof(struct sysinfo))) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
 extern int ptrace_traceme(void);
 extern void set_single_step(struct thread *thread);