udevadm: monitor - use epoll

diff --git a/TODO b/TODO
index 6906aa89d1b2b9ee4fff0eac93185d8e5c8666f6..c09613313155991315c83aa4db823257c263dd84 100644 (file)
--- a/TODO
+++ b/TODO
@@ -1,3 +1,6 @@
+  - get rid of select()
+  - use signalfd instead of ppoll()
+
   - remove deprecated trigger --type=failed logic
 
   - remove deprecated BUS=, SYSFS{}=, ID= keys

diff --git a/udev/udevadm-monitor.c b/udev/udevadm-monitor.c
index a587e8cc0f10daf2cf1c44e56d6a78893b85fdae..8fe9e0527caec281419faead86fd2c475ad224ab 100644 (file)
--- a/udev/udevadm-monitor.c
+++ b/udev/udevadm-monitor.c
@@ -27,18 +27,18 @@
 #include <sys/time.h>
 #include <sys/socket.h>
 #include <sys/un.h>
-#include <sys/select.h>
+#include <sys/epoll.h>
 #include <linux/types.h>
 #include <linux/netlink.h>
 
 #include "udev.h"
 
-static int udev_exit;
+static bool udev_exit;
 
 static void sig_handler(int signum)
 {
        if (signum == SIGINT || signum == SIGTERM)
-               udev_exit = 1;
+               udev_exit = true;
 }
 
 static void print_device(struct udev_device *device, const char *source, int prop)
@@ -69,14 +69,16 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
        struct sigaction act;
        sigset_t mask;
        int option;
-       int prop = 0;
-       int print_kernel = 0;
-       int print_udev = 0;
+       bool prop = false;
+       bool print_kernel = false;
+       bool print_udev = false;
        struct udev_list_node subsystem_match_list;
        struct udev_list_node tag_match_list;
        struct udev_monitor *udev_monitor = NULL;
        struct udev_monitor *kernel_monitor = NULL;
-       fd_set readfds;
+       int fd_ep = -1;
+       int fd_kernel = -1, fd_udev = -1;
+       struct epoll_event ep_kernel, ep_udev;
        int rc = 0;
 
        static const struct option options[] = {
@@ -92,6 +94,7 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
 
        udev_list_init(&subsystem_match_list);
        udev_list_init(&tag_match_list);
+
        for (;;) {
                option = getopt_long(argc, argv, "pekus:t:h", options, NULL);
                if (option == -1)
@@ -100,13 +103,13 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
                switch (option) {
                case 'p':
                case 'e':
-                       prop = 1;
+                       prop = true;
                        break;
                case 'k':
-                       print_kernel = 1;
+                       print_kernel = true;
                        break;
                case 'u':
-                       print_udev = 1;
+                       print_udev = true;
                        break;
                case 's':
                        {
@@ -138,8 +141,8 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
        }
 
        if (!print_kernel && !print_udev) {
-               print_kernel = 1;
-               print_udev =1;
+               print_kernel = true;
+               print_udev = true;
        }
 
        /* set signal handlers */
@@ -154,6 +157,12 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
        sigaddset(&mask, SIGTERM);
        sigprocmask(SIG_UNBLOCK, &mask, NULL);
 
+       fd_ep = epoll_create1(EPOLL_CLOEXEC);
+       if (fd_ep < 0) {
+               err(udev, "error creating epoll fd: %m\n");
+               goto out;
+       }
+
        printf("monitor will print the received events for:\n");
        if (print_udev) {
                struct udev_list_entry *entry;
@@ -165,6 +174,7 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
                        goto out;
                }
                udev_monitor_set_receive_buffer_size(udev_monitor, 128*1024*1024);
+               fd_udev = udev_monitor_get_fd(udev_monitor);
 
                udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
                        const char *subsys = udev_list_entry_get_name(entry);
@@ -186,8 +196,18 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
                        rc = 2;
                        goto out;
                }
+
+               memset(&ep_udev, 0, sizeof(struct epoll_event));
+               ep_udev.events = EPOLLIN;
+               ep_udev.data.fd = fd_udev;
+               if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_udev, &ep_udev) < 0) {
+                       err(udev, "fail to add fd to epoll: %m\n");
+                       goto out;
+               }
+
                printf("UDEV - the event which udev sends out after rule processing\n");
        }
+
        if (print_kernel) {
                struct udev_list_entry *entry;
 
@@ -198,6 +218,7 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
                        goto out;
                }
                udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024);
+               fd_kernel = udev_monitor_get_fd(kernel_monitor);
 
                udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
                        const char *subsys = udev_list_entry_get_name(entry);
@@ -211,49 +232,56 @@ int udevadm_monitor(struct udev *udev, int argc, char *argv[])
                        rc = 4;
                        goto out;
                }
+
+               memset(&ep_kernel, 0, sizeof(struct epoll_event));
+               ep_kernel.events = EPOLLIN;
+               ep_kernel.data.fd = fd_kernel;
+               if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_kernel, &ep_kernel) < 0) {
+                       err(udev, "fail to add fd to epoll: %m\n");
+                       goto out;
+               }
+
                printf("KERNEL - the kernel uevent\n");
        }
        printf("\n");
 
        while (!udev_exit) {
                int fdcount;
+               struct epoll_event ev[4];
+               int i;
 
-               FD_ZERO(&readfds);
-               if (kernel_monitor != NULL)
-                       FD_SET(udev_monitor_get_fd(kernel_monitor), &readfds);
-               if (udev_monitor != NULL)
-                       FD_SET(udev_monitor_get_fd(udev_monitor), &readfds);
-
-               fdcount = select(MAX(udev_monitor_get_fd(kernel_monitor), udev_monitor_get_fd(udev_monitor))+1,
-                                &readfds, NULL, NULL, NULL);
+               fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
                if (fdcount < 0) {
                        if (errno != EINTR)
                                fprintf(stderr, "error receiving uevent message: %m\n");
                        continue;
                }
 
-               if ((kernel_monitor != NULL) && FD_ISSET(udev_monitor_get_fd(kernel_monitor), &readfds)) {
-                       struct udev_device *device;
+               for (i = 0; i < fdcount; i++) {
+                       if (ev[i].data.fd == fd_kernel && ev[i].events & EPOLLIN) {
+                               struct udev_device *device;
 
-                       device = udev_monitor_receive_device(kernel_monitor);
-                       if (device == NULL)
-                               continue;
-                       print_device(device, "KERNEL", prop);
-                       udev_device_unref(device);
-               }
+                               device = udev_monitor_receive_device(kernel_monitor);
+                               if (device == NULL)
+                                       continue;
+                               print_device(device, "KERNEL", prop);
+                               udev_device_unref(device);
+                       }
 
-               if ((udev_monitor != NULL) && FD_ISSET(udev_monitor_get_fd(udev_monitor), &readfds)) {
-                       struct udev_device *device;
+                       if (ev[i].data.fd == fd_udev && ev[i].events & EPOLLIN) {
+                               struct udev_device *device;
 
-                       device = udev_monitor_receive_device(udev_monitor);
-                       if (device == NULL)
-                               continue;
-                       print_device(device, "UDEV", prop);
-                       udev_device_unref(device);
+                               device = udev_monitor_receive_device(udev_monitor);
+                               if (device == NULL)
+                                       continue;
+                               print_device(device, "UDEV", prop);
+                               udev_device_unref(device);
+                       }
                }
        }
-
 out:
+       if (fd_ep >= 0)
+               close(fd_ep);
        udev_monitor_unref(udev_monitor);
        udev_monitor_unref(kernel_monitor);
        udev_list_cleanup_entries(udev, &subsystem_match_list);