[Mesa-dev] [PATCH 1/4] gallium/u_queue: fix random crashes when the app calls exit()

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

This fixes:
    vdpauinfo: ../lib/CodeGen/TargetPassConfig.cpp:579: virtual void
    llvm::TargetPassConfig::addMachinePasses(): Assertion `TPI && IPI &&
    "Pass ID not registered!"' failed.

v2: use list_head, switch the call order in destroy

Cc: 13.0 17.0 <mesa-stable at lists.freedesktop.org>
---
 src/gallium/auxiliary/util/u_queue.c | 76 +++++++++++++++++++++++++++++++++++-
 src/gallium/auxiliary/util/u_queue.h |  4 ++
 2 files changed, 78 insertions(+), 2 deletions(-)

diff --git a/src/gallium/auxiliary/util/u_queue.c b/src/gallium/auxiliary/util/u_queue.c
index 4da5d8e..52cfc0a 100644
--- a/src/gallium/auxiliary/util/u_queue.c
+++ b/src/gallium/auxiliary/util/u_queue.c
@@ -22,20 +22,82 @@
  * The above copyright notice and this permission notice (including the
  * next paragraph) shall be included in all copies or substantial portions
  * of the Software.
  */
 
 #include "u_queue.h"
 #include "u_memory.h"
 #include "u_string.h"
 #include "os/os_time.h"
 
+static void util_queue_killall_and_wait(struct util_queue *queue);
+
+/****************************************************************************
+ * Wait for all queues to assert idle when exit() is called.
+ *
+ * Otherwise, C++ static variable destructors can be called while threads
+ * are using the static variables.
+ */
+
+static once_flag atexit_once_flag = ONCE_FLAG_INIT;
+static struct list_head queue_list;
+pipe_static_mutex(exit_mutex);
+
+static void
+atexit_handler(void)
+{
+   struct util_queue *iter;
+
+   pipe_mutex_lock(exit_mutex);
+   /* Wait for all queues to assert idle. */
+   LIST_FOR_EACH_ENTRY(iter, &queue_list, head) {
+      util_queue_killall_and_wait(iter);
+   }
+   pipe_mutex_unlock(exit_mutex);
+}
+
+static void
+global_init(void)
+{
+   LIST_INITHEAD(&queue_list);
+   atexit(atexit_handler);
+}
+
+static void
+add_to_atexit_list(struct util_queue *queue)
+{
+   call_once(&atexit_once_flag, global_init);
+
+   pipe_mutex_lock(exit_mutex);
+   LIST_ADD(&queue->head, &queue_list);
+   pipe_mutex_unlock(exit_mutex);
+}
+
+static void
+remove_from_atexit_list(struct util_queue *queue)
+{
+   struct util_queue *iter, *tmp;
+
+   pipe_mutex_lock(exit_mutex);
+   LIST_FOR_EACH_ENTRY_SAFE(iter, tmp, &queue_list, head) {
+      if (iter == queue) {
+         LIST_DEL(&iter->head);
+         break;
+      }
+   }
+   pipe_mutex_unlock(exit_mutex);
+}
+
+/****************************************************************************
+ * util_queue implementation
+ */
+
 static void
 util_queue_fence_signal(struct util_queue_fence *fence)
 {
    pipe_mutex_lock(fence->mutex);
    fence->signalled = true;
    pipe_condvar_broadcast(fence->cond);
    pipe_mutex_unlock(fence->mutex);
 }
 
 void
@@ -97,20 +159,21 @@ static PIPE_THREAD_ROUTINE(util_queue_thread_func, input)
    }
 
    /* signal remaining jobs before terminating */
    pipe_mutex_lock(queue->lock);
    while (queue->jobs[queue->read_idx].job) {
       util_queue_fence_signal(queue->jobs[queue->read_idx].fence);
 
       queue->jobs[queue->read_idx].job = NULL;
       queue->read_idx = (queue->read_idx + 1) % queue->max_jobs;
    }
+   queue->num_queued = 0; /* reset this when exiting the thread */
    pipe_mutex_unlock(queue->lock);
    return 0;
 }
 
 bool
 util_queue_init(struct util_queue *queue,
                 const char *name,
                 unsigned max_jobs,
                 unsigned num_threads)
 {
@@ -150,49 +213,58 @@ util_queue_init(struct util_queue *queue,
          if (i == 0) {
             /* no threads created, fail */
             goto fail;
          } else {
             /* at least one thread created, so use it */
             queue->num_threads = i+1;
             break;
          }
       }
    }
+
+   add_to_atexit_list(queue);
    return true;
 
 fail:
    FREE(queue->threads);
 
    if (queue->jobs) {
       pipe_condvar_destroy(queue->has_space_cond);
       pipe_condvar_destroy(queue->has_queued_cond);
       pipe_mutex_destroy(queue->lock);
       FREE(queue->jobs);
    }
    /* also util_queue_is_initialized can be used to check for success */
    memset(queue, 0, sizeof(*queue));
    return false;
 }
 
-void
-util_queue_destroy(struct util_queue *queue)
+static void
+util_queue_killall_and_wait(struct util_queue *queue)
 {
    unsigned i;
 
    /* Signal all threads to terminate. */
    pipe_mutex_lock(queue->lock);
    queue->kill_threads = 1;
    pipe_condvar_broadcast(queue->has_queued_cond);
    pipe_mutex_unlock(queue->lock);
 
    for (i = 0; i < queue->num_threads; i++)
       pipe_thread_wait(queue->threads[i]);
+}
+
+void
+util_queue_destroy(struct util_queue *queue)
+{
+   util_queue_killall_and_wait(queue);
+   remove_from_atexit_list(queue);
 
    pipe_condvar_destroy(queue->has_space_cond);
    pipe_condvar_destroy(queue->has_queued_cond);
    pipe_mutex_destroy(queue->lock);
    FREE(queue->jobs);
    FREE(queue->threads);
 }
 
 void
 util_queue_fence_init(struct util_queue_fence *fence)
diff --git a/src/gallium/auxiliary/util/u_queue.h b/src/gallium/auxiliary/util/u_queue.h
index 351315c..335813f 100644
--- a/src/gallium/auxiliary/util/u_queue.h
+++ b/src/gallium/auxiliary/util/u_queue.h
@@ -27,20 +27,21 @@
 /* Job queue with execution in a separate thread.
  *
  * Jobs can be added from any thread. After that, the wait call can be used
  * to wait for completion of the job.
  */
 
 #ifndef U_QUEUE_H
 #define U_QUEUE_H
 
 #include "os/os_thread.h"
+#include "util/list.h"
 
 /* Job completion fence.
  * Put this into your job structure.
  */
 struct util_queue_fence {
    pipe_mutex mutex;
    pipe_condvar cond;
    int signalled;
 };
 
@@ -59,20 +60,23 @@ struct util_queue {
    pipe_mutex lock;
    pipe_condvar has_queued_cond;
    pipe_condvar has_space_cond;
    pipe_thread *threads;
    int num_queued;
    unsigned num_threads;
    int kill_threads;
    int max_jobs;
    int write_idx, read_idx; /* ring buffer pointers */
    struct util_queue_job *jobs;
+
+   /* for cleanup at exit(), protected by exit_mutex */
+   struct list_head head;
 };
 
 bool util_queue_init(struct util_queue *queue,
                      const char *name,
                      unsigned max_jobs,
                      unsigned num_threads);
 void util_queue_destroy(struct util_queue *queue);
 void util_queue_fence_init(struct util_queue_fence *fence);
 void util_queue_fence_destroy(struct util_queue_fence *fence);
 
-- 
2.7.4