[test] Implement ut for sigsuspend

demos/linux-ltp/syscalls-occlum

@@ -1152,7 +1152,6 @@ rt_sigaction03 rt_sigaction03
 rt_sigprocmask01 rt_sigprocmask01
 #rt_sigprocmask02 rt_sigprocmask02
 rt_sigqueueinfo01 rt_sigqueueinfo01
-rt_sigsuspend01 rt_sigsuspend01
 rt_sigtimedwait01 rt_sigtimedwait01
 rt_tgsigqueueinfo01 rt_tgsigqueueinfo01
 
@@ -1448,8 +1447,6 @@ sigprocmask01 sigprocmask01
 
 sigrelse01 sigrelse01
 
-sigsuspend01 sigsuspend01
-
 sigtimedwait01 sigtimedwait01
 
 sigwait01 sigwait01

src/libos/src/interrupt/mod.rs

@@ -38,15 +38,25 @@ pub fn do_handle_interrupt(
 /// Broadcast interrupts to threads by sending POSIX signals.
 pub fn broadcast_interrupts() -> Result<usize> {
     let should_interrupt_thread = |thread: &&ThreadRef| -> bool {
-        let should_interrupt = thread.process().is_forced_to_exit()
+        if thread.process().is_forced_to_exit() || thread.is_forced_to_stop() {
-            || thread.is_forced_to_stop()
+            return true;
-            || !thread.process().sig_queues().read().unwrap().empty();
+        }
 
-        // Check Thread::sig_mask to avoid wrong interrupts
+        let sig_mask_guard = thread.sig_mask().read().unwrap();
-        let sig_queues = thread.sig_queues().read().unwrap();
+        let interested = !*sig_mask_guard;
-        let sig_mask = thread.sig_mask().read().unwrap();
+        drop(sig_mask_guard);
 
-        should_interrupt || sig_queues.has_valid_signal(&sig_mask)
+        let thread_pending_sig = thread.sig_queues().read().unwrap().pending() & interested;
+        if !thread_pending_sig.empty() {
+            return true;
+        }
+
+        let process_pending_sig =
+            thread.process().sig_queues().read().unwrap().pending() & interested;
+        if !process_pending_sig.empty() {
+            return true;
+        }
+        false
     };
 
     let num_signaled_threads = crate::process::table::get_all_threads()

src/libos/src/net/syscalls.rs

@@ -7,7 +7,7 @@ use super::io_multiplexing::{AsEpollFile, EpollCtl, EpollFile, EpollFlags, FdSet
 use fs::{CreationFlags, File, FileDesc, FileRef};
 use misc::resource_t;
 use process::Process;
-use signal::{do_sigprocmask, sigset_t, MaskOp, SigSet};
+use signal::{sigset_t, MaskOp, SigSet, SIGKILL, SIGSTOP};
 use std::convert::TryFrom;
 use time::{timespec_t, timeval_t};
 use util::mem_util::from_user;
@@ -723,9 +723,9 @@ pub fn do_select(
     ret
 }
 
-#[derive(Clone, Copy, Debug)]
+#[derive(Debug)]
 #[repr(C)]
-pub struct Pselect6sig {
+pub struct sigset_argpack {
     ss: *const sigset_t,
     ss_len: size_t,
 }
@@ -736,11 +736,13 @@ pub fn do_pselect6(
     writefds: *mut libc::fd_set,
     exceptfds: *mut libc::fd_set,
     timeout: *mut timespec_t,
-    sig_data: *const Pselect6sig,
+    sig_data: *const sigset_argpack,
 ) -> Result<isize> {
     let mut is_set_sig = false;
-    let mut original_sig_set = sigset_t::default();
+    let mut prev_mask = SigSet::default();
+    let thread = current!();
 
+    // Set signal mask
     if !sig_data.is_null() {
         from_user::check_ptr(sig_data)?;
         let user_sig_data = unsafe { &*(sig_data) };
@@ -750,15 +752,20 @@ pub fn do_pselect6(
             if user_sig_data.ss_len != std::mem::size_of::<sigset_t>() {
                 return_errno!(EINVAL, "unexpected sigset size");
             }
-            let op_and_set = {
+            let update_mask = {
-                let op = MaskOp::SetMask;
                 let sigset = user_sig_data.ss;
                 from_user::check_ptr(sigset)?;
                 let set = unsafe { &*sigset };
-                Some((op, set))
+                let mut set = SigSet::from_c(unsafe { *sigset });
+                // According to man pages, "it is not possible to block SIGKILL or SIGSTOP.
+                // Attempts to do so are silently ignored."
+                set -= SIGKILL;
+                set -= SIGSTOP;
+                set
             };
-
+            let mut curr_mask = thread.sig_mask().write().unwrap();
-            do_sigprocmask::do_rt_sigprocmask(op_and_set, Some(&mut original_sig_set))?;
+            prev_mask = *curr_mask;
+            *curr_mask = update_mask;
         }
     }
 
@@ -815,12 +822,8 @@ pub fn do_pselect6(
 
     // Restore the original signal mask
     if is_set_sig {
-        let op_and_set = {
+        let mut curr_mask = thread.sig_mask().write().unwrap();
-            let op = MaskOp::SetMask;
+        *curr_mask = prev_mask;
-            let set = &original_sig_set;
-            Some((op, set))
-        };
-        do_sigprocmask::do_rt_sigprocmask(op_and_set, None)?;
     }
 
     ret

src/libos/src/signal/do_sigpending.rs

@@ -6,6 +6,7 @@ pub fn do_sigpending() -> Result<SigSet> {
 
     let thread = current!();
     let process = thread.process();
+
     let pending = (thread.sig_queues().read().unwrap().pending()
         | process.sig_queues().read().unwrap().pending())
         & *thread.sig_mask().read().unwrap();

src/libos/src/signal/do_sigprocmask.rs

@@ -2,24 +2,15 @@ use super::constants::*;
 use super::{sigset_t, SigSet};
 use crate::prelude::*;
 
-pub fn do_rt_sigprocmask(
+pub fn do_rt_sigprocmask(op_and_set: Option<(MaskOp, &SigSet)>) -> Result<SigSet> {
-    op_and_set: Option<(MaskOp, &sigset_t)>,
+    debug!("do_rt_sigprocmask: op_and_set: {:?}", op_and_set,);
-    oldset: Option<&mut sigset_t>,
-) -> Result<()> {
-    debug!(
-        "do_rt_sigprocmask: op_and_set: {:?}, oldset: {:?}",
-        op_and_set.map(|(op, set)| (op, SigSet::from_c(*set))),
-        oldset
-    );
 
     let thread = current!();
     let mut sig_mask = thread.sig_mask().write().unwrap();
-    if let Some(oldset) = oldset {
+    let old_mask = *sig_mask;
-        *oldset = sig_mask.to_c();
+    if let Some((op, set)) = op_and_set {
-    }
-    if let Some((op, &set)) = op_and_set {
         let set = {
-            let mut set = SigSet::from_c(set);
+            let mut set = *set;
             // According to man pages, "it is not possible to block SIGKILL or SIGSTOP.
             // Attempts to do so are silently ignored."
             set -= SIGKILL;
@@ -38,7 +29,7 @@ pub fn do_rt_sigprocmask(
             }
         };
     }
-    Ok(())
+    Ok(old_mask)
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]

src/libos/src/signal/do_sigsuspend.rs

@@ -1,36 +1,46 @@
-use super::do_sigprocmask::do_rt_sigprocmask;
+use super::constants::*;
 use super::do_sigtimedwait::PendingSigWaiter;
 use super::{sigset_t, MaskOp, SigNum, SigSet, Signal};
 use crate::prelude::*;
 
-pub fn do_sigsuspend(mask: &sigset_t) -> Result<()> {
+pub fn do_sigsuspend(mask: &SigSet) -> Result<()> {
     debug!("do_sigsuspend: mask: {:?}", mask);
 
     let thread = current!();
     let process = thread.process().clone();
-    let mut original_sig_set = sigset_t::default();
 
     // Set signal mask
-    let op_and_set = Some((MaskOp::SetMask, mask));
+    let update_mask = {
-    do_rt_sigprocmask(op_and_set, Some(&mut original_sig_set))?;
+        let mut set = *mask;
+        // According to man pages, "it is not possible to block SIGKILL or SIGSTOP.
+        // Attempts to do so are silently ignored."
+        set -= SIGKILL;
+        set -= SIGSTOP;
+        set
+    };
 
-    let interest = SigSet::from_c(!*mask);
+    let mut curr_mask = thread.sig_mask().write().unwrap();
-    let pending_sig_waiter = PendingSigWaiter::new(thread, process, interest);
+    let prev_mask = *curr_mask;
+    *curr_mask = update_mask;
+    drop(curr_mask);
 
-    match pending_sig_waiter.suspend() {
+    // Suspend for interest signal
+    let interest = !update_mask;
+    let pending_sig_waiter = PendingSigWaiter::new(thread.clone(), process, interest);
+
+    let err = match pending_sig_waiter.suspend() {
         Ok(_) => {
-            // Restore the original signal mask
+            errno!(EINTR, "Wait for EINTR signal successfully")
-            let op_and_set = {
-                let op = MaskOp::SetMask;
-                let set = &original_sig_set;
-                Some((op, set))
-            };
-            do_rt_sigprocmask(op_and_set, None).unwrap();
-            Err(errno!(EINTR, "Wait for EINTR signal successfully"))
         }
         Err(_) => {
             // Impossible path
-            Err(errno!(EFAULT, "No interesting, pending signal"))
+            errno!(EFAULT, "No interesting, pending signal")
         }
-    }
+    };
+
+    // Restore the original signal mask
+    let mut curr_mask = thread.sig_mask().write().unwrap();
+    *curr_mask = prev_mask;
+
+    Err(err)
 }

src/libos/src/signal/do_sigtimedwait.rs

@@ -136,10 +136,9 @@ impl PendingSigWaiter {
                     if has_interest_signal(&self.interest, &self.thread, &self.process) {
                         return Ok(());
                     }
-                } else {
-                    // Impossible case
-                    return Err(e);
                 }
+                // Impossible case
+                return Err(e);
             }
         }
     }
@@ -164,17 +163,11 @@ impl Drop for PendingSigWaiter {
 }
 
 fn has_interest_signal(interest: &SigSet, thread: &ThreadRef, process: &ProcessRef) -> bool {
-    let blocked = !*interest;
+    let pending = (thread.sig_queues().read().unwrap().pending()
-    process
+        | process.sig_queues().read().unwrap().pending())
-        .sig_queues()
+        & *interest;
-        .write()
+
-        .unwrap()
+    !pending.empty()
-        .has_valid_signal(&blocked)
-        || thread
-            .sig_queues()
-            .write()
-            .unwrap()
-            .has_valid_signal(&blocked)
 }
 
 fn dequeue_pending_signal(

src/libos/src/signal/mod.rs

@@ -22,6 +22,7 @@ mod do_kill;
 mod do_sigaction;
 mod do_sigaltstack;
 mod do_sigpending;
+mod do_sigprocmask;
 mod do_sigreturn;
 mod do_sigsuspend;
 mod do_sigtimedwait;
@@ -35,4 +36,3 @@ mod signals;
 mod syscalls;
 
 pub mod constants;
-pub mod do_sigprocmask;

src/libos/src/signal/sig_queues.rs

@@ -38,41 +38,6 @@ impl SigQueues {
         self.count == 0
     }
 
-    pub fn has_valid_signal(&self, blocked: &SigSet) -> bool {
-        // Fast path for the common case of no pending signals
-        if self.empty() {
-            return false;
-        }
-
-        // Check standard signals.
-        for &signum in &Self::ORDERED_STD_SIGS {
-            if blocked.contains(signum) {
-                continue;
-            }
-
-            let queue = self.get_std_queue(signum);
-            if queue.is_some() {
-                return true;
-            }
-        }
-
-        // If no standard signals, then check real-time signals.
-        for signum in MIN_RT_SIG_NUM..=MAX_RT_SIG_NUM {
-            let signum = unsafe { SigNum::from_u8_unchecked(signum) };
-            if blocked.contains(signum) {
-                continue;
-            }
-
-            let queue = self.get_rt_queue(signum);
-            if !queue.is_empty() {
-                return true;
-            }
-        }
-
-        // There must be pending but blocked signals
-        false
-    }
-
     pub fn enqueue(&mut self, signal: Box<dyn Signal>) {
         let signum = signal.num();
         if signum.is_std() {

src/libos/src/signal/syscalls.rs

@@ -89,23 +89,25 @@ pub fn do_rt_sigprocmask(
     if sigset_size != std::mem::size_of::<sigset_t>() {
         return_errno!(EINVAL, "unexpected sigset size");
     }
+
+    let mut set_sig = SigSet::default();
     let op_and_set = {
         if !set_ptr.is_null() {
             let op = MaskOp::from_u32(how as u32)?;
-            let set = unsafe { &*set_ptr };
+            set_sig = SigSet::from_c(unsafe { *set_ptr });
-            Some((op, set))
+            Some((op, &set_sig))
         } else {
             None
         }
     };
-    let old_set = {
+
-        if !oldset_ptr.is_null() {
+    let old_set = super::do_sigprocmask::do_rt_sigprocmask(op_and_set)?;
-            Some(unsafe { &mut *oldset_ptr })
+    if !oldset_ptr.is_null() {
-        } else {
+        unsafe {
-            None
+            *oldset_ptr = old_set.to_c();
         }
-    };
+    }
-    super::do_sigprocmask::do_rt_sigprocmask(op_and_set, old_set)?;
+
     Ok(0)
 }
 
@@ -201,7 +203,7 @@ pub fn do_rt_sigsuspend(mask_ptr: *const sigset_t) -> Result<isize> {
             return_errno!(EFAULT, "ptr must not be null");
         }
         from_user::check_ptr(mask_ptr)?;
-        unsafe { *mask_ptr }
+        SigSet::from_c(unsafe { *mask_ptr })
     };
 
     super::do_sigsuspend::do_sigsuspend(&mask)?;

src/libos/src/syscall/mod.rs

@@ -45,7 +45,7 @@ use crate::net::{
     do_epoll_pwait, do_epoll_wait, do_getpeername, do_getsockname, do_getsockopt, do_listen,
     do_poll, do_ppoll, do_pselect6, do_recvfrom, do_recvmsg, do_select, do_sendmmsg, do_sendmsg,
     do_sendto, do_setsockopt, do_shutdown, do_socket, do_socketpair, mmsghdr, msghdr, msghdr_mut,
-    Pselect6sig,
+    sigset_argpack,
 };
 use crate::process::{
     do_arch_prctl, do_clone, do_execve, do_exit, do_exit_group, do_futex, do_get_robust_list,
@@ -367,7 +367,7 @@ macro_rules! process_syscall_table_with_callback {
             (Readlinkat = 267) => do_readlinkat(dirfd: i32, path: *const i8, buf: *mut u8, size: usize),
             (Fchmodat = 268) => do_fchmodat(dirfd: i32, path: *const i8, mode: u16),
             (Faccessat = 269) => do_faccessat(dirfd: i32, path: *const i8, mode: u32, flags: u32),
-            (Pselect6 = 270) => do_pselect6(nfds: c_int, readfds: *mut libc::fd_set, writefds: *mut libc::fd_set, exceptfds: *mut libc::fd_set, timeout: *mut timespec_t, data: *const Pselect6sig),
+            (Pselect6 = 270) => do_pselect6(nfds: c_int, readfds: *mut libc::fd_set, writefds: *mut libc::fd_set, exceptfds: *mut libc::fd_set, timeout: *mut timespec_t, data: *const sigset_argpack),
             (Ppoll = 271) => do_ppoll(fds: *mut libc::pollfd, nfds: libc::nfds_t, timeout_ts: *const timespec_t, sigmask: *const sigset_t),
             (Unshare = 272) => handle_unsupported(),
             (SetRobustList = 273) => do_set_robust_list(list_head_ptr: *mut RobustListHead, len: usize),

test/Makefile

@@ -21,8 +21,8 @@ TEST_DEPS := client data_sink naughty_child
 TESTS ?= env empty hello_world malloc mmap file fs_perms getpid spawn sched pipe time timerfd \
 	truncate readdir mkdir open stat link symlink chmod chown tls pthread system_info rlimit \
 	server server_epoll unix_socket cout hostfs cpuid rdtsc device sleep exit_group posix_flock \
-	ioctl fcntl eventfd emulate_syscall access signal sysinfo prctl rename procfs wait pselect \
+	ioctl fcntl eventfd emulate_syscall access signal sysinfo prctl rename procfs pselect sigsuspend \
-	spawn_attribute exec statfs random umask pgrp vfork mount flock utimes shm epoll brk posix_shm
+	wait spawn_attribute exec statfs random umask pgrp vfork mount flock utimes shm epoll brk posix_shm
 # Benchmarks: need to be compiled and run by bench-% target
 BENCHES := spawn_and_exit_latency pipe_throughput unix_socket_throughput
 

test/pselect/main.c

@@ -6,6 +6,7 @@
 #include <errno.h>
 #include <stdint.h> // for uint64_t
 #include <pthread.h>
+#include "test.h"
 
 // Signal handler for SIGUSR1
 void sigusr1_handler(int sig) {
@@ -36,13 +37,13 @@ int main() {
     // Spawn new thread for sending signal when call pselect syscall
     pthread_t signal_thread;
     if (pthread_create(&signal_thread, NULL, send_signal, &main_thread_id) != 0) {
-        perror("pthread_create");
+        THROW_ERROR("pthread_create");
         return 1;
     }
 
     int timer_fd = timerfd_create(CLOCK_REALTIME, 0);
     if (timer_fd == -1) {
-        perror("timerfd_create");
+        THROW_ERROR("timerfd_create");
         return 1;
     }
 
@@ -52,7 +53,7 @@ int main() {
     timerValue.it_interval.tv_sec = 0;
     timerValue.it_interval.tv_nsec = 0;
     if (timerfd_settime(timer_fd, 0, &timerValue, NULL) == -1) {
-        perror("timerfd_settime");
+        THROW_ERROR("timerfd_settime");
         close(timer_fd);
         return 1;
     }
@@ -63,17 +64,17 @@ int main() {
 
     int ready = pselect(timer_fd + 1, &readfds, NULL, NULL, NULL, &sigmask);
 
-    if (ready == -1) {
+    if (ready > 0) {
-        perror("pselect6");
-    } else if (ready == 0) {
-        // Impossible case
-        printf("No input - timeout reached\n");
-    } else {
         if (FD_ISSET(timer_fd, &readfds)) {
             printf("Timer expired, pselect blocked SIGUSR1 signal successfully\n");
             uint64_t expirations;
             read(timer_fd, &expirations, sizeof(expirations));
         }
+    } else if (ready == 0) {
+        // Impossible case
+        printf("No input - timeout reached\n");
+    } else {
+        THROW_ERROR("failed to pselect");
     }
 
     pthread_join(signal_thread, NULL);

test/sigsuspend/Makefile

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

test/sigsuspend/main.c

@@ -0,0 +1,64 @@
+#include <sys/select.h>
+#include <sys/timerfd.h>
+#include <signal.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdint.h> // for uint64_t
+#include <pthread.h>
+#include "test.h"
+
+// Signal handler for SIGUSR1
+void sigusr_handler(int sig) {
+    printf("Received signals: %d. ", sig);
+}
+
+void *send_signal(void *arg) {
+    pthread_t main_thread_id = *(pthread_t *)arg;
+    sleep(1);
+    pthread_kill(main_thread_id, SIGUSR1);
+    sleep(1);
+    pthread_kill(main_thread_id, SIGUSR2);
+    return NULL;
+}
+
+int main() {
+    // Set SIGUSR1 signal action
+    struct sigaction sa1;
+    sa1.sa_handler = sigusr_handler;
+    sigemptyset(&sa1.sa_mask);
+    sa1.sa_flags = 0;
+    sigaction(SIGUSR1, &sa1, NULL);
+
+    // Set SIGUSR2 signal action
+    struct sigaction sa2;
+    sa2.sa_handler = sigusr_handler;
+    sigemptyset(&sa2.sa_mask);
+    sa2.sa_flags = 0;
+    sigaction(SIGUSR2, &sa2, NULL);
+
+    // Mask for blocking SIGUSR1 signal
+    sigset_t sigmask;
+    sigemptyset(&sigmask);
+    sigaddset(&sigmask, SIGUSR1);
+
+    // Access pthread id
+    pthread_t main_thread_id = pthread_self();
+
+    // Spawn new thread for sending signal when call pselect syscall
+    pthread_t signal_thread;
+    if (pthread_create(&signal_thread, NULL, send_signal, &main_thread_id) != 0) {
+        THROW_ERROR("failed to create pthread");
+        return 1;
+    }
+
+    int ret = sigsuspend(&sigmask);
+    if (ret == -1) {
+        printf("Signal received, the rt_sigsuspend syscall returns successfully\n");
+    } else {
+        THROW_ERROR("failed to call rt_sigsuspend syscall");
+    }
+
+    pthread_join(signal_thread, NULL);
+    return 0;
+}