s3: Work better without the aio sighandler

Refuse async I/O if we can't set up the signal handler

diff --git a/source3/smbd/aio.c b/source3/smbd/aio.c
index a5a0e44738d4f54ee1217bfdaddf674c36d41e93..dbce120dc60c0dc17bad919ca90898674fea3583 100644 (file)
--- a/source3/smbd/aio.c
+++ b/source3/smbd/aio.c
@@ -67,11 +67,17 @@ static void smbd_aio_signal_handler(struct tevent_context *ev_ctx,
 }
 
 
-static void initialize_async_io_handler(void)
+static bool initialize_async_io_handler(void)
 {
+       static bool tried_signal_setup = false;
+
        if (aio_signal_event) {
-               return;
+               return true;
+       }
+       if (tried_signal_setup) {
+               return false;
        }
+       tried_signal_setup = true;
 
        aio_signal_event = tevent_add_signal(smbd_event_context(),
                                             smbd_event_context(),
@@ -79,7 +85,8 @@ static void initialize_async_io_handler(void)
                                             smbd_aio_signal_handler,
                                             NULL);
        if (!aio_signal_event) {
-               exit_server("Failed to setup RT_SIGNAL_AIO handler");
+               DEBUG(10, ("Failed to setup RT_SIGNAL_AIO handler\n"));
+               return false;
        }
 
        /* tevent supports 100 signal with SA_SIGINFO */
@@ -145,7 +152,9 @@ NTSTATUS schedule_aio_read_and_X(connection_struct *conn,
        int ret;
 
        /* Ensure aio is initialized. */
-       initialize_async_io_handler();
+       if (!initialize_async_io_handler()) {
+               return NT_STATUS_RETRY;
+       }
 
        if (fsp->base_fsp != NULL) {
                /* No AIO on streams yet */
@@ -250,7 +259,9 @@ NTSTATUS schedule_aio_write_and_X(connection_struct *conn,
        int ret;
 
        /* Ensure aio is initialized. */
-       initialize_async_io_handler();
+       if (!initialize_async_io_handler()) {
+               return NT_STATUS_RETRY;
+       }
 
        if (fsp->base_fsp != NULL) {
                /* No AIO on streams yet */
@@ -382,7 +393,9 @@ NTSTATUS schedule_smb2_aio_read(connection_struct *conn,
        int ret;
 
        /* Ensure aio is initialized. */
-       initialize_async_io_handler();
+       if (!initialize_async_io_handler()) {
+               return NT_STATUS_RETRY;
+       }
 
        if (fsp->base_fsp != NULL) {
                /* No AIO on streams yet */
@@ -478,7 +491,9 @@ NTSTATUS schedule_aio_smb2_write(connection_struct *conn,
        int ret;
 
        /* Ensure aio is initialized. */
-       initialize_async_io_handler();
+       if (!initialize_async_io_handler()) {
+               return NT_STATUS_RETRY;
+       }
 
        if (fsp->base_fsp != NULL) {
                /* No AIO on streams yet */