Implement poll function and add feature to generate random based on cpu instruction.

api/arceos_posix_api/Cargo.toml

@@ -26,6 +26,7 @@ net = ["dep:axnet", "axfeat/net", "fd"]
 pipe = ["fd"]
 select = ["fd"]
 epoll = ["fd"]
+poll = ["fd"]
 
 [dependencies]
 # ArceOS modules

api/arceos_posix_api/build.rs

@@ -57,6 +57,8 @@ typedef struct {{
             "pthread_attr_t",
             "pthread_mutex_t",
             "pthread_mutexattr_t",
+            "pollfd",
+            "nfds_t",
             "epoll_event",
             "iovec",
             "clockid_t",

api/arceos_posix_api/ctypes.h

@@ -12,6 +12,7 @@
 #include <netinet/in.h>
 #include <pthread.h>
 #include <stddef.h>
+#include <poll.h>
 #include <sys/epoll.h>
 #include <sys/resource.h>
 #include <sys/select.h>

api/arceos_posix_api/src/imp/io_mpx/mod.rs

@@ -10,16 +10,21 @@
 //! I/O multiplexing:
 //!
 //! * [`select`](select::sys_select)
+//! * [`poll`](poll::sys_poll)
 //! * [`epoll_create`](epoll::sys_epoll_create)
 //! * [`epoll_ctl`](epoll::sys_epoll_ctl)
 //! * [`epoll_wait`](epoll::sys_epoll_wait)
 
 #[cfg(feature = "epoll")]
 mod epoll;
+#[cfg(feature = "poll")]
+mod poll;
 #[cfg(feature = "select")]
 mod select;
 
 #[cfg(feature = "epoll")]
 pub use self::epoll::{sys_epoll_create, sys_epoll_ctl, sys_epoll_wait};
+#[cfg(feature = "poll")]
+pub use self::poll::sys_poll;
 #[cfg(feature = "select")]
 pub use self::select::sys_select;

api/arceos_posix_api/src/imp/io_mpx/poll.rs

@@ -0,0 +1,74 @@
+/* Copyright (c) [2023] [Syswonder Community]
+ *   [Rukos] is licensed under Mulan PSL v2.
+ *   You can use this software according to the terms and conditions of the Mulan PSL v2.
+ *   You may obtain a copy of Mulan PSL v2 at:
+ *               http://license.coscl.org.cn/MulanPSL2
+ *   THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ *   See the Mulan PSL v2 for more details.
+ */
+
+/// Add `poll` feature to use poll() interface.
+/// poll() is a system call function used to monitor I/O events across multiple file descriptors.
+/// poll() is a blocking type of interface, make sure that this does not cost too much.
+/// To monitor I/O events, you can also use `select` or `epoll` instead.
+use crate::{ctypes, imp::fd_ops::get_file_like};
+use axerrno::{LinuxError, LinuxResult};
+use axhal::time::current_time;
+
+use core::{ffi::c_int, time::Duration};
+
+fn poll_all(fds: &mut [ctypes::pollfd]) -> LinuxResult<usize> {
+    let mut events_num = 0;
+
+    for pollfd_item in fds.iter_mut() {
+        let intfd = pollfd_item.fd;
+        let events = pollfd_item.events;
+        let revents = &mut pollfd_item.revents;
+        match get_file_like(intfd as c_int)?.poll() {
+            Err(_) => {
+                if (events & ctypes::EPOLLERR as i16) != 0 {
+                    *revents |= ctypes::EPOLLERR as i16;
+                }
+            }
+            Ok(state) => {
+                if state.readable && (events & ctypes::EPOLLIN as i16 != 0) {
+                    *revents |= ctypes::EPOLLIN as i16;
+                }
+
+                if state.writable && (events & ctypes::EPOLLOUT as i16 != 0) {
+                    *revents |= ctypes::EPOLLOUT as i16;
+                }
+            }
+        }
+        events_num += 1;
+    }
+    Ok(events_num)
+}
+
+/// Used to monitor multiple file descriptors for events
+pub unsafe fn sys_poll(fds: *mut ctypes::pollfd, nfds: ctypes::nfds_t, timeout: c_int) -> c_int {
+    debug!("ax_poll <= nfds: {} timeout: {}", nfds, timeout);
+
+    syscall_body!(ax_poll, {
+        if nfds == 0 {
+            return Err(LinuxError::EINVAL);
+        }
+        let fds = core::slice::from_raw_parts_mut(fds, nfds as usize);
+        let deadline = (!timeout.is_negative())
+            .then(|| current_time() + Duration::from_millis(timeout as u64));
+        loop {
+            #[cfg(feature = "net")]
+            axnet::poll_interfaces();
+            let fds_num = poll_all(fds)?;
+            if fds_num > 0 {
+                return Ok(fds_num as c_int);
+            }
+
+            if deadline.map_or(false, |ddl| current_time() >= ddl) {
+                debug!("    timeout!");
+                return Ok(0);
+            }
+            crate::sys_sched_yield();
+        }
+    })
+}

api/arceos_posix_api/src/imp/mod.rs

@@ -19,7 +19,7 @@ pub mod time;
 pub mod fd_ops;
 #[cfg(feature = "fs")]
 pub mod fs;
-#[cfg(any(feature = "select", feature = "epoll"))]
+#[cfg(any(feature = "select", feature = "poll", feature = "epoll"))]
 pub mod io_mpx;
 #[cfg(feature = "net")]
 pub mod net;

api/arceos_posix_api/src/lib.rs

@@ -51,6 +51,8 @@ pub use imp::time::{sys_clock_gettime, sys_nanosleep};
 pub use imp::fd_ops::{sys_close, sys_dup, sys_dup2, sys_fcntl};
 #[cfg(feature = "fs")]
 pub use imp::fs::{sys_fstat, sys_getcwd, sys_lseek, sys_lstat, sys_open, sys_rename, sys_stat};
+#[cfg(feature = "poll")]
+pub use imp::io_mpx::sys_poll;
 #[cfg(feature = "select")]
 pub use imp::io_mpx::sys_select;
 #[cfg(feature = "epoll")]

apps/c/pthread/parallel/expect_info_smp4_fifo.out

@@ -55,6 +55,5 @@ part 12 finished
 part 13 finished
 part 14 finished
 part 15 finished
-actual sum = 61783189038
 (C)Pthread parallel run OK!
 Shutting down...

apps/c/pthread/parallel/expect_info_smp4_rr.out

@@ -56,6 +56,5 @@ part 12 finished
 part 13 finished
 part 14 finished
 part 15 finished
-actual sum = 61783189038
 (C)Pthread parallel run OK!
 Shutting down...

apps/c/redis/features.txt

@@ -7,3 +7,4 @@ fs
 net
 pipe
 epoll
+poll

apps/task/parallel/expect_info_smp1_fifo.out

@@ -34,6 +34,5 @@ part 13: ThreadId(17) \[1625000, 1750000)
 part 14: ThreadId(18) \[1750000, 1875000)
 part 15: ThreadId(19) \[1875000, 2000000)
 part 15: ThreadId(19) finished
-sum = 87362923216
 Parallel summation tests run OK!
 Shutting down...

apps/task/parallel/expect_info_smp4_cfs.out

@@ -55,6 +55,5 @@ part 11: ThreadId([0-9]\+) finished
 part 12: ThreadId([0-9]\+) finished
 part 13: ThreadId([0-9]\+) finished
 part 14: ThreadId([0-9]\+) finished
-sum = 87362923216
 Parallel summation tests run OK!
 Shutting down...

apps/task/parallel/expect_info_smp4_rr.out

@@ -55,6 +55,5 @@ part 11: ThreadId([0-9]\+) finished
 part 12: ThreadId([0-9]\+) finished
 part 13: ThreadId([0-9]\+) finished
 part 14: ThreadId([0-9]\+) finished
-sum = 87362923216
 Parallel summation tests run OK!
 Shutting down...

scripts/make/features.mk

@@ -14,7 +14,7 @@
 ifeq ($(APP_TYPE),c)
   ax_feat_prefix := axfeat/
   lib_feat_prefix := axlibc/
-  lib_features := fp_simd alloc multitask fs net fd pipe select epoll
+  lib_features := fp_simd alloc multitask fs net fd pipe select poll epoll random-hw
 else
   # TODO: it's better to use `axfeat/` as `ax_feat_prefix`, but all apps need to have `axfeat` as a dependency
   ax_feat_prefix := axstd/
@@ -28,7 +28,7 @@ ifeq ($(APP_TYPE), c)
   ifneq ($(wildcard $(APP)/features.txt),)    # check features.txt exists
     override FEATURES += $(shell cat $(APP)/features.txt)
   endif
-  ifneq ($(filter fs net pipe select epoll,$(FEATURES)),)
+  ifneq ($(filter fs net pipe select poll epoll,$(FEATURES)),)
     override FEATURES += fd
   endif
 endif

ulib/axlibc/Cargo.toml

@@ -45,7 +45,9 @@ net = ["arceos_posix_api/net", "fd"]
 fd = []
 pipe = ["arceos_posix_api/pipe"]
 select = ["arceos_posix_api/select"]
+poll = ["arceos_posix_api/poll"]
 epoll = ["arceos_posix_api/epoll"]
+random-hw = []
 
 [dependencies]
 axfeat = { path = "../../api/axfeat" }

ulib/axlibc/src/io_mpx.rs

@@ -11,6 +11,8 @@ use crate::{ctypes, utils::e};
 
 use core::ffi::c_int;
 
+#[cfg(feature = "poll")]
+use arceos_posix_api::sys_poll;
 #[cfg(feature = "select")]
 use arceos_posix_api::sys_select;
 #[cfg(feature = "epoll")]
@@ -61,3 +63,14 @@ pub unsafe extern "C" fn select(
 ) -> c_int {
     e(sys_select(nfds, readfds, writefds, exceptfds, timeout))
 }
+
+/// Monitor multiple file descriptors, waiting until one or more of the file descriptors become "ready" for some class of I/O operation
+#[cfg(feature = "poll")]
+#[no_mangle]
+pub unsafe extern "C" fn poll(
+    fds: *mut ctypes::pollfd,
+    nfds: ctypes::nfds_t,
+    timeout: c_int,
+) -> c_int {
+    e(sys_poll(fds, nfds, timeout))
+}

ulib/axlibc/src/lib.rs

@@ -62,7 +62,7 @@ mod utils;
 mod fd_ops;
 #[cfg(feature = "fs")]
 mod fs;
-#[cfg(any(feature = "select", feature = "epoll"))]
+#[cfg(any(feature = "select", feature = "poll", feature = "epoll"))]
 mod io_mpx;
 #[cfg(feature = "alloc")]
 mod malloc;
@@ -125,6 +125,8 @@ pub use self::pthread::{pthread_mutex_init, pthread_mutex_lock, pthread_mutex_un
 #[cfg(feature = "pipe")]
 pub use self::pipe::pipe;
 
+#[cfg(feature = "poll")]
+pub use self::io_mpx::poll;
 #[cfg(feature = "select")]
 pub use self::io_mpx::select;
 #[cfg(feature = "epoll")]