Add support for sysinfo syscall

src/libos/src/entry.rs

@@ -8,6 +8,7 @@ use crate::exception::*;
 use crate::fs::HostStdioFds;
 use crate::process::ProcessFilter;
 use crate::signal::SigNum;
+use crate::time::up_time::init;
 use crate::util::log::LevelFilter;
 use crate::util::mem_util::from_untrusted::*;
 use crate::util::sgx::allow_debug as sgx_allow_debug;
@@ -72,6 +73,9 @@ pub extern "C" fn occlum_ecall_init(log_level: *const c_char, instance_dir: *con
         }
 
         HAS_INIT.store(true, Ordering::SeqCst);
+
+        // Init boot up time stamp here.
+        time::up_time::init();
     });
 
     0

src/libos/src/misc/mod.rs

@@ -1,7 +1,9 @@
 use super::*;
 
 mod rlimit;
+mod sysinfo;
 mod uname;
 
 pub use self::rlimit::{do_prlimit, resource_t, rlimit_t, ResourceLimits};
+pub use self::sysinfo::{do_sysinfo, sysinfo_t};
 pub use self::uname::{do_uname, utsname_t};

src/libos/src/misc/sysinfo.rs

@@ -0,0 +1,35 @@
+use super::*;
+use crate::process::table;
+use crate::time::up_time::get;
+use crate::vm::USER_SPACE_VM_MANAGER;
+use config::LIBOS_CONFIG;
+
+// This structure aligns with Linux kernels which are later than v2.3.23 (i386) and v2.3.48 (all architectures)
+#[repr(C)]
+#[derive(Clone, Default)]
+pub struct sysinfo_t {
+    uptime: i64,
+    loads: [u64; 3],
+    totalram: u64,
+    freeram: u64,
+    sharedram: u64,
+    bufferram: u64,
+    totalswap: u64,
+    freeswap: u64,
+    procs: u16,
+    totalhigh: u64,
+    freehigh: u64,
+    mem_unit: u32,
+}
+
+pub fn do_sysinfo() -> Result<sysinfo_t> {
+    let info = sysinfo_t {
+        uptime: time::up_time::get().unwrap().as_secs() as i64, // Duration can't be negative
+        totalram: USER_SPACE_VM_MANAGER.get_total_size() as u64,
+        freeram: USER_SPACE_VM_MANAGER.get_free_size() as u64,
+        procs: table::get_all_processes().len() as u16,
+        mem_unit: 1,
+        ..Default::default()
+    };
+    Ok(info)
+}

src/libos/src/syscall/mod.rs

@@ -25,7 +25,7 @@ use crate::fs::{
     do_readlink, do_readv, do_rename, do_rmdir, do_sendfile, do_stat, do_sync, do_truncate,
     do_unlink, do_write, do_writev, iovec_t, File, FileDesc, FileRef, HostStdioFds, Stat,
 };
-use crate::misc::{resource_t, rlimit_t, utsname_t};
+use crate::misc::{resource_t, rlimit_t, sysinfo_t, utsname_t};
 use crate::net::{
     do_accept, do_accept4, do_bind, do_connect, do_epoll_create, do_epoll_create1, do_epoll_ctl,
     do_epoll_pwait, do_epoll_wait, do_getpeername, do_getsockname, do_getsockopt, do_listen,
@@ -176,7 +176,7 @@ macro_rules! process_syscall_table_with_callback {
             (Gettimeofday = 96) => do_gettimeofday(tv_u: *mut timeval_t),
             (Getrlimit = 97) => handle_unsupported(),
             (Getrusage = 98) => handle_unsupported(),
-            (SysInfo = 99) => handle_unsupported(),
+            (SysInfo = 99) => do_sysinfo(info: *mut sysinfo_t),
             (Times = 100) => handle_unsupported(),
             (Ptrace = 101) => handle_unsupported(),
             (Getuid = 102) => do_getuid(),
@@ -755,6 +755,13 @@ fn do_brk(new_brk_addr: usize) -> Result<isize> {
     Ok(ret_brk_addr as isize)
 }
 
+fn do_sysinfo(info: *mut sysinfo_t) -> Result<isize> {
+    check_mut_ptr(info)?;
+    let info = unsafe { &mut *info };
+    *info = misc::do_sysinfo()?;
+    Ok(0)
+}
+
 // TODO: handle tz: timezone_t
 fn do_gettimeofday(tv_u: *mut timeval_t) -> Result<isize> {
     check_mut_ptr(tv_u)?;

src/libos/src/time/mod.rs

@@ -8,6 +8,7 @@ use std::{fmt, u64};
 use syscall::SyscallNum;
 
 mod profiler;
+pub mod up_time;
 
 pub use profiler::GLOBAL_PROFILER;
 

src/libos/src/time/up_time.rs

@@ -0,0 +1,19 @@
+use super::{do_clock_gettime, ClockID};
+use std::time::Duration;
+
+lazy_static! {
+    static ref BOOT_TIME_STAMP: Duration = do_clock_gettime(ClockID::CLOCK_MONOTONIC_RAW)
+        .unwrap()
+        .as_duration();
+}
+
+pub fn init() {
+    *BOOT_TIME_STAMP;
+}
+
+pub fn get() -> Option<Duration> {
+    do_clock_gettime(ClockID::CLOCK_MONOTONIC_RAW)
+        .unwrap()
+        .as_duration()
+        .checked_sub(*BOOT_TIME_STAMP)
+}

src/libos/src/vm/mod.rs

@@ -13,6 +13,7 @@ use self::vm_layout::VMLayout;
 use self::vm_manager::{VMManager, VMMapOptionsBuilder};
 
 pub use self::process_vm::{MMapFlags, MRemapFlags, ProcessVM, ProcessVMBuilder, VMPerms};
+pub use self::user_space_vm::USER_SPACE_VM_MANAGER;
 pub use self::vm_range::VMRange;
 
 pub fn do_mmap(

test/Makefile

@@ -22,7 +22,7 @@ TEST_DEPS := client data_sink
 TESTS ?= env empty hello_world malloc mmap file fs_perms getpid spawn sched pipe time \
 	truncate readdir mkdir open stat link symlink chmod chown tls pthread uname rlimit \
 	server server_epoll unix_socket cout hostfs cpuid rdtsc device sleep exit_group \
-	ioctl fcntl eventfd emulate_syscall access signal
+	ioctl fcntl eventfd emulate_syscall access signal sysinfo
 # Benchmarks: need to be compiled and run by bench-% target
 BENCHES := spawn_and_exit_latency pipe_throughput unix_socket_throughput
 

test/sysinfo/Makefile

@@ -0,0 +1,5 @@
+include ../test_common.mk
+
+EXTRA_C_FLAGS :=
+EXTRA_LINK_FLAGS :=
+BIN_ARGS :=

test/sysinfo/main.c

@@ -0,0 +1,56 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/sysinfo.h>
+#include <spawn.h>
+#include <sys/wait.h>
+#include "test.h"
+
+int test_sysinfo() {
+    const long MIN = 60;
+    const long HOUR = MIN * 60;
+    const long DAY = HOUR * 24;
+    const double MEGABYTE = 1024 * 1024;
+    struct sysinfo info;
+    int child_pid, status;
+
+    // Test uptime
+    sleep(3);
+
+    // Test procs number
+    int ret = posix_spawn(&child_pid, "/bin/getpid", NULL, NULL, NULL, NULL);
+    if (ret < 0 ) {
+        THROW_ERROR("spawn process error");
+    }
+
+    sysinfo (&info);
+
+    printf ("system uptime: %ld days, %ld:%02ld:%02ld\n",
+            info.uptime / DAY, (info.uptime % DAY) / HOUR,
+            (info.uptime % HOUR) / MIN, info.uptime % MIN);
+    printf ("total RAM: %5.1f MB\n", info.totalram / MEGABYTE);
+    printf ("free RAM: %5.1f MB\n", info.freeram / MEGABYTE);
+    printf ("process count: %d\n", info.procs);
+
+    if (info.uptime % MIN < 3) {
+        THROW_ERROR("system uptime error");
+    }
+
+    if (info.procs != 2 ) {
+        THROW_ERROR("system process count error");
+    }
+
+    ret = wait4(-1, &status, 0, NULL);
+    if (ret < 0) {
+        THROW_ERROR("failed to wait4 the child proces");
+    }
+
+    return 0;
+}
+
+static test_case_t test_cases[] = {
+    TEST_CASE(test_sysinfo),
+};
+
+int main() {
+    return test_suite_run(test_cases, ARRAY_SIZE(test_cases));
+}