devices: Hoist epoll event buffer allocation out of event loops

Author: mtjhrc

src/devices/src/virtio/block/worker.rs

@@ -105,8 +105,8 @@ impl BlockWorker {
             &EpollEvent::new(EventSet::IN, stop_ev_fd as u64),
         );
 
+        let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
         loop {
-            let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
             match epoll.wait(epoll_events.len(), -1, epoll_events.as_mut_slice()) {
                 Ok(ev_cnt) => {
                     for event in &epoll_events[0..ev_cnt] {

src/devices/src/virtio/fs/worker.rs

@@ -89,8 +89,8 @@ impl FsWorker {
             &EpollEvent::new(EventSet::IN, stop_ev_fd as u64),
         );
 
+        let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
         loop {
-            let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
             match epoll.wait(epoll_events.len(), -1, epoll_events.as_mut_slice()) {
                 Ok(ev_cnt) => {
                     for event in &epoll_events[0..ev_cnt] {

src/devices/src/virtio/net/worker.rs

@@ -125,8 +125,8 @@ impl NetWorker {
             ),
         );
 
+        let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
         loop {
-            let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
             match epoll.wait(epoll_events.len(), -1, epoll_events.as_mut_slice()) {
                 Ok(ev_cnt) => {
                     for event in &epoll_events[0..ev_cnt] {

src/devices/src/virtio/snd/worker.rs

@@ -139,8 +139,8 @@ impl SndWorker {
             )
             .unwrap();
 
+        let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
         loop {
-            let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
             match epoll.wait(epoll_events.len(), -1, epoll_events.as_mut_slice()) {
                 Ok(ev_cnt) => {
                     for event in &epoll_events[0..ev_cnt] {

src/devices/src/virtio/vsock/muxer_thread.rs

@@ -175,8 +175,8 @@ impl MuxerThread {
     fn work(mut self) {
         let mut thread_rng = rng();
         self.create_lisening_ipc_sockets();
+        let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
         loop {
-            let mut epoll_events = vec![EpollEvent::new(EventSet::empty(), 0); 32];
             match self
                 .epoll
                 .wait(epoll_events.len(), -1, epoll_events.as_mut_slice())