diff options
Diffstat (limited to 'main/strongswan/0001-vici-Asynchronize-debug-logging.patch')
| -rw-r--r-- | main/strongswan/0001-vici-Asynchronize-debug-logging.patch | 169 |
1 files changed, 0 insertions, 169 deletions
diff --git a/main/strongswan/0001-vici-Asynchronize-debug-logging.patch b/main/strongswan/0001-vici-Asynchronize-debug-logging.patch deleted file mode 100644 index c756f9d3e8..0000000000 --- a/main/strongswan/0001-vici-Asynchronize-debug-logging.patch +++ /dev/null @@ -1,169 +0,0 @@ -From 856ea64129cdc7ee56969524d7abaaae08c22c6a Mon Sep 17 00:00:00 2001 -From: Martin Willi <martin@revosec.ch> -Date: Thu, 2 Jul 2015 09:10:21 +0200 -Subject: [PATCH] vici: Asynchronize debug logging - -The vici logger uses the listener_t.log() callback to raise vici events. - -When doing so, it holds the bus lock as reader while acquiring the vici socket -mutex (1). If at the same time the vici socket enables a writer, that thread -tries to lock the watcher mutex (2). The watcher thread uses debugging while -holding the lock, i.e. acquires the bus read lock (3). - -(1) bus.rlock -> vici.lock! -(2) vici.lock -> watcher.lock! -(3) watcher.lock -> bus.rlock! - -This all actually would resolve just fine, as we have a shared read lock on the -bus. However, under Windows we seem to have a strict writer preference when -acquiring the rwlock (4). This results in blocking read locks until any pending -write lock can be fulfilled, and makes the constellation deadlock. The relevant -threads are: - -Thread (1) -6 0x71313d25 in wait_ at threading/windows/mutex.c:137 -7 0x7054c8a2 in find_entry at vici_socket.c:201 -8 0x7054d690 in send_ at vici_socket.c:624 -9 0x7054f6c1 in send_op at vici_dispatcher.c:119 -10 0x705502c1 in raise_event at vici_dispatcher.c:469 -12 0x704c3878 in log_cb at bus/bus.c:332 -13 0x712c7c3a in invoke_function at collections/linked_list.c:414 -14 0x704c3a63 in vlog at bus/bus.c:400 -15 0x704c3b36 in log_ at bus/bus.c:430 -18 0x70508f1f in process_response at sa/ikev2/task_manager_v2.c:664 -20 0x704f5430 in process_message at sa/ike_sa.c:1369 -21 0x704e3823 in execute at processing/jobs/process_message_job.c:74 -22 0x712e629f in process_job at processing/processor.c:235 - -Thread (2) -4 0x71313b61 in lock at threading/windows/mutex.c:66 -5 0x712e81fd in add at processing/watcher.c:441 -6 0x712e1ab9 in add_watcher at networking/streams/stream.c:213 -7 0x712e1b4d in on_write at networking/streams/stream.c:237 -8 0x7054d606 in _cb_enable_writer at vici_socket.c:609 -9 0x712e5e34 in execute at processing/jobs/callback_job.c:77 -10 0x712e629f in process_job at processing/processor.c:235 - -Thread (3) -3 0x71313f38 in read_lock at threading/windows/rwlock.c:74 -4 0x704c3971 in vlog at bus/bus.c:373 -5 0x704cc156 in dbg_bus at daemon.c:126 -6 0x712e7bf9 in watch at processing/watcher.c:316 -7 0x712e5e34 in execute at processing/jobs/callback_job.c:77 -8 0x712e629f in process_job at processing/processor.c:235 - -Thread (4) -3 0x71313f70 in write_lock at threading/windows/rwlock.c:82 -4 0x704c378b in remove_logger at bus/bus.c:290 -5 0x704cb284 in listener_unregister at control/controller.c:166 -6 0x713136cd in thread_cleanup_pop at threading/windows/thread.c:558 -8 0x704cb94e in initiate at control/controller.c:435 -9 0x70553996 in _cb_initiate at vici_control.c:187 -12 0x7054d200 in _cb_process_queue at vici_socket.c:508 -13 0x712e5e34 in execute at processing/jobs/callback_job.c:77 -14 0x712e629f in process_job at processing/processor.c:235 - -To avoid such a situation, we dissolve the (1) lock sequence. It's actually -never good practice to acquire shared locks during bus hooks, as it is -problematic if we raise bus events while holding the lock. We do so by -raising vici events for log message asynchronously, but of curse must keep -log order as is using a synchronized queue. ---- - src/libcharon/plugins/vici/vici_logger.c | 48 +++++++++++++++++++++++++++++++- - 1 file changed, 47 insertions(+), 1 deletion(-) - -diff --git a/src/libcharon/plugins/vici/vici_logger.c b/src/libcharon/plugins/vici/vici_logger.c -index cffd65b..6d3584e 100644 ---- a/src/libcharon/plugins/vici/vici_logger.c -+++ b/src/libcharon/plugins/vici/vici_logger.c -@@ -18,6 +18,7 @@ - - #include <daemon.h> - #include <threading/mutex.h> -+#include <processing/jobs/callback_job.h> - - typedef struct private_vici_logger_t private_vici_logger_t; - -@@ -42,11 +43,54 @@ struct private_vici_logger_t { - int recursive; - - /** -+ * List of messages to raise async events -+ */ -+ linked_list_t *queue; -+ -+ /** - * Mutex to synchronize logging - */ - mutex_t *mutex; - }; - -+/** -+ * Async callback to raise events for queued messages -+ */ -+static job_requeue_t raise_events(private_vici_logger_t *this) -+{ -+ vici_message_t *message; -+ u_int count; -+ -+ this->mutex->lock(this->mutex); -+ count = this->queue->get_count(this->queue); -+ this->queue->remove_first(this->queue, (void**)&message); -+ this->mutex->unlock(this->mutex); -+ -+ if (count > 0) -+ { -+ this->dispatcher->raise_event(this->dispatcher, "log", 0, message); -+ } -+ if (count > 1) -+ { -+ return JOB_REQUEUE_DIRECT; -+ } -+ return JOB_REQUEUE_NONE; -+} -+ -+/** -+ * Queue a message for async processing -+ */ -+static void queue_messsage(private_vici_logger_t *this, vici_message_t *message) -+{ -+ this->queue->insert_last(this->queue, message); -+ if (this->queue->get_count(this->queue) == 1) -+ { -+ lib->processor->queue_job(lib->processor, (job_t*) -+ callback_job_create((callback_job_cb_t)raise_events, -+ this, NULL, NULL)); -+ } -+} -+ - METHOD(logger_t, log_, void, - private_vici_logger_t *this, debug_t group, level_t level, int thread, - ike_sa_t* ike_sa, const char *msg) -@@ -75,7 +119,7 @@ METHOD(logger_t, log_, void, - message = builder->finalize(builder); - if (message) - { -- this->dispatcher->raise_event(this->dispatcher, "log", 0, message); -+ queue_messsage(this, message); - } - } - this->recursive--; -@@ -101,6 +145,7 @@ METHOD(vici_logger_t, destroy, void, - private_vici_logger_t *this) - { - manage_commands(this, FALSE); -+ this->queue->destroy_offset(this->queue, offsetof(vici_message_t, destroy)); - this->mutex->destroy(this->mutex); - free(this); - } -@@ -121,6 +166,7 @@ vici_logger_t *vici_logger_create(vici_dispatcher_t *dispatcher) - .destroy = _destroy, - }, - .dispatcher = dispatcher, -+ .queue = linked_list_create(), - .mutex = mutex_create(MUTEX_TYPE_RECURSIVE), - ); - --- -2.4.6 - |