Add nDPId / nDPIsrvd command line option to use poll() on Linux instead of the default epoll().add/event-io-abstraction

Signed-off-by: Toni Uhlig <matzeton@googlemail.com>

3 files changed, 35 insertions, 9 deletions

diff --git a/nDPId-test.c b/nDPId-test.c
index 170bf4c2e..48c0e2b70 100644
--- a/nDPId-test.c
+++ b/nDPId-test.c
@@ -311,7 +311,7 @@ static void * nDPIsrvd_mainloop_thread(void * const arg)
 #ifdef ENABLE_EPOLL
     if (nio_use_epoll(&io, 32) != NIO_SUCCESS)
 #else
-    if (nio_use_poll(&io, 32) != NIO_SUCCESS)
+    if (nio_use_poll(&io, nDPIsrvd_MAX_REMOTE_DESCRIPTORS) != NIO_SUCCESS)
 #endif
     {
         logger(1, "%s", "Error creating nDPIsrvd poll/epoll event I/O");
diff --git a/nDPId.c b/nDPId.c
index 63311be1a..9fada5e40 100644
--- a/nDPId.c
+++ b/nDPId.c
@@ -467,6 +467,9 @@ static struct
     uint8_t enable_zlib_compression;
 #endif
     uint8_t enable_data_analysis;
+#ifdef ENABLE_EPOLL
+    uint8_t use_poll;
+#endif
     /* subopts */
     unsigned long long int max_flows_per_thread;
     unsigned long long int max_idle_flows_per_thread;
@@ -4408,9 +4411,10 @@ static void run_pcap_loop(struct nDPId_reader_thread * const reader_thread)
             struct nio io;
             nio_init(&io);
 #ifdef ENABLE_EPOLL
-            if (nio_use_epoll(&io, 32) != 0)
+            if ((nDPId_options.use_poll == 0 && nio_use_epoll(&io, 32) != NIO_SUCCESS)
+                || (nDPId_options.use_poll != 0 && nio_use_poll(&io, nDPIsrvd_MAX_REMOTE_DESCRIPTORS) != NIO_SUCCESS))
 #else
-            if (nio_use_poll(&io, 32) != 0)
+            if (nio_use_poll(&io, nDPIsrvd_MAX_REMOTE_DESCRIPTORS) != NIO_SUCCESS)
 #endif
             {
                 logger(1, "%s", "Event I/O poll/epoll setup failed");
@@ -4908,7 +4912,7 @@ static void print_usage(char const * const arg0)
         "Usage: %s "
         "[-i pcap-file/interface] [-I] [-E] [-B bpf-filter]\n"
         "\t  \t"
-        "[-l] [-L logfile] [-c address] "
+        "[-l] [-L logfile] [-c address] [-e]"
         "[-d] [-p pidfile]\n"
         "\t  \t"
         "[-u user] [-g group] "
@@ -4929,6 +4933,8 @@ static void print_usage(char const * const arg0)
         "\t-L\tLog all messages to a log file.\n"
         "\t-c\tPath to a UNIX socket (nDPIsrvd Collector) or a custom UDP endpoint.\n"
         "\t  \tDefault: %s\n"
+        "\t-e\tUse poll() instead of epoll().\n"
+        "\t  \tDefault: epoll() on Linux, poll() otherwise\n"
         "\t-d\tFork into background after initialization.\n"
         "\t-p\tWrite the daemon PID to the given file path.\n"
         "\t  \tDefault: %s\n"
@@ -4990,7 +4996,7 @@ static int nDPId_parse_options(int argc, char ** argv)
 {
     int opt;
 
-    while ((opt = getopt(argc, argv, "i:IEB:lL:c:dp:u:g:P:C:J:S:a:Azo:vh")) != -1)
+    while ((opt = getopt(argc, argv, "i:IEB:lL:c:edp:u:g:P:C:J:S:a:Azo:vh")) != -1)
     {
         switch (opt)
         {
@@ -5018,6 +5024,13 @@ static int nDPId_parse_options(int argc, char ** argv)
             case 'c':
                 set_cmdarg(&nDPId_options.collector_address, optarg);
                 break;
+            case 'e':
+#ifdef ENABLE_EPOLL
+                nDPId_options.use_poll = 1;
+#else
+                logger_early(1, "%s", "nDPId was built w/o epoll() support, poll() is already the default");
+#endif
+                break;
             case 'd':
                 daemonize_enable();
                 break;
diff --git a/nDPIsrvd.c b/nDPIsrvd.c
index 614cb9df6..a4d7457fe 100644
--- a/nDPIsrvd.c
+++ b/nDPIsrvd.c
@@ -92,7 +92,10 @@ static struct
     struct cmdarg group;
     nDPIsrvd_ull max_remote_descriptors;
     nDPIsrvd_ull max_write_buffers;
-    int bufferbloat_fallback_to_blocking;
+    uint8_t bufferbloat_fallback_to_blocking;
+#ifdef ENABLE_EPOLL
+    uint8_t use_poll;
+#endif
 } nDPIsrvd_options = {.pidfile = CMDARG(nDPIsrvd_PIDFILE),
                       .collector_un_sockpath = CMDARG(COLLECTOR_UNIX_SOCKET),
                       .distributor_un_sockpath = CMDARG(DISTRIBUTOR_UNIX_SOCKET),
@@ -796,6 +799,13 @@ static int nDPIsrvd_parse_options(int argc, char ** argv)
             case 'c':
                 set_cmdarg(&nDPIsrvd_options.collector_un_sockpath, optarg);
                 break;
+            case 'e':
+#ifdef ENABLE_EPOLL
+                nDPIsrvd_options.use_poll = 1;
+#else
+                logger_early(1, "%s", "nDPIsrvd was built w/o epoll() support, poll() is already the default");
+#endif
+                break;
             case 'd':
                 daemonize_enable();
                 break;
@@ -838,7 +848,7 @@ static int nDPIsrvd_parse_options(int argc, char ** argv)
             default:
                 fprintf(stderr, "%s\n", get_nDPId_version());
                 fprintf(stderr,
-                        "Usage: %s [-l] [-L logfile] [-c path-to-unix-sock] [-d] [-p pidfile]\n"
+                        "Usage: %s [-l] [-L logfile] [-c path-to-unix-sock] [-e] [-d] [-p pidfile]\n"
                         "\t[-s path-to-distributor-unix-socket] [-S distributor-host:port]\n"
                         "\t[-m max-remote-descriptors] [-u user] [-g group]\n"
                         "\t[-C max-buffered-json-lines] [-D]\n"
@@ -847,6 +857,8 @@ static int nDPIsrvd_parse_options(int argc, char ** argv)
                         "\t-L\tLog all messages to a log file.\n"
                         "\t-c\tPath to a listening UNIX socket (nDPIsrvd Collector).\n"
                         "\t  \tDefault: %s\n"
+                        "\t-e\tUse poll() instead of epoll().\n"
+                        "\t  \tDefault: epoll() on Linux, poll() otherwise\n"
                         "\t-d\tFork into background after initialization.\n"
                         "\t-p\tWrite the daemon PID to the given file path.\n"
                         "\t  \tDefault: %s\n"
@@ -1463,9 +1475,10 @@ static int mainloop(struct nio * const io)
 static int setup_event_queue(struct nio * const io)
 {
 #ifdef ENABLE_EPOLL
-    if (nio_use_epoll(io, 32) != NIO_SUCCESS)
+    if ((nDPIsrvd_options.use_poll == 0 && nio_use_epoll(io, 32) != NIO_SUCCESS)
+        || (nDPIsrvd_options.use_poll != 0 && nio_use_poll(io, nDPIsrvd_MAX_REMOTE_DESCRIPTORS) != NIO_SUCCESS))
 #else
-    if (nio_use_poll(io, 32) != NIO_SUCCESS)
+    if (nio_use_poll(io, nDPIsrvd_MAX_REMOTE_DESCRIPTORS) != NIO_SUCCESS)
 #endif
     {
         logger(1, "%s", "Event I/O poll/epoll setup failed");