diff options
Diffstat (limited to 'runtime/transport/transport.c')
| -rw-r--r-- | runtime/transport/transport.c | 42 |
1 files changed, 27 insertions, 15 deletions
diff --git a/runtime/transport/transport.c b/runtime/transport/transport.c index 8cc624a9..fd50c92f 100644 --- a/runtime/transport/transport.c +++ b/runtime/transport/transport.c @@ -47,16 +47,6 @@ int _stp_transport_open(struct transport_info *info); #include "procfs.c" -/* - * _stp_streaming - boolean, are we using 'streaming' output? - */ -static int _stp_streaming(void) -{ - if (_stp_transport_mode == STP_TRANSPORT_PROC) - return 1; - return 0; -} - /* send commands with timeout and retry */ int _stp_transport_send (int type, void *data, int len) { @@ -128,15 +118,23 @@ static void _stp_handle_subbufs_consumed(int pid, struct consumed_info *info) } #endif +/* common cleanup code. */ +/* This is called from the kernel thread when an exit was requested */ +/* by stpd or the exit() function. It is also called by transport_close() */ +/* when the module is removed. In that case "dont_rmmod" is set to 1. */ +/* We need to call it both times because we want to clean up properly */ +/* when someone does /sbin/rmmod on a loaded systemtap module. */ static void _stp_cleanup_and_exit (int dont_rmmod) { - int failures; - kbug("cleanup_and_exit (%d)\n", dont_rmmod); if (!_stp_exit_called) { + int failures; + + /* we only want to do this stuff once */ _stp_exit_called = 1; kbug("calling probe_exit\n"); + /* tell the stap-generated code to unload its probes, etc */ probe_exit(); kbug("done with probe_exit\n"); @@ -150,15 +148,20 @@ static void _stp_cleanup_and_exit (int dont_rmmod) } #endif kbug("transport_send STP_EXIT\n"); + /* tell stpd to exit (if it is still there) */ _stp_transport_send(STP_EXIT, &dont_rmmod, sizeof(int)); kbug("done with transport_send STP_EXIT\n"); _stp_kill_time(); + + /* free print buffers */ + _stp_print_cleanup(); } } /* * _stp_work_queue - periodically check for IO or exit + * This is run by a kernel thread and may sleep. */ static void _stp_work_queue (void *data) { @@ -176,9 +179,11 @@ static void _stp_work_queue (void *data) /* if exit flag is set AND we have finished with probe_start() */ if (unlikely(_stp_exit_flag && atomic_read(&_stp_start_finished))) { _stp_cleanup_and_exit(0); +/* cancel_delayed_work(&stp_exit); flush_workqueue(_stp_wq); wake_up_interruptible(&_stp_proc_wq); +*/ } else queue_delayed_work(_stp_wq, &stp_exit, STP_WORK_TIMER); } @@ -186,8 +191,8 @@ static void _stp_work_queue (void *data) /** * _stp_transport_close - close proc and relayfs channels * - * This must be called after all I/O is done, probably at the end - * of module cleanup. + * This is called automatically when the module is unloaded. + * */ void _stp_transport_close() { @@ -230,7 +235,7 @@ int _stp_transport_open(struct transport_info *info) _stp_target = info->target; #ifdef STP_RELAYFS - if (!_stp_streaming()) { + if (_stp_transport_mode == STP_TRANSPORT_RELAYFS) { if (info->buf_size) { unsigned size = info->buf_size * 1024 * 1024; subbuf_size = ((size >> 2) + 1) * 65536; @@ -268,11 +273,18 @@ int _stp_transport_init(void) { kbug("transport_init from %ld %ld\n", (long)_stp_pid, (long)current->pid); + /* create print buffers */ + if (_stp_print_init() < 0) + return -1; + + /* set up procfs communications */ if (_stp_register_procfs() < 0) return -1; + /* create workqueue of kernel threads */ _stp_wq = create_workqueue("systemtap"); queue_delayed_work(_stp_wq, &stp_exit, STP_WORK_TIMER); + return 0; } |