On Fri, Apr 16, 2021 at 11:08:56AM +0300, Vladimir Sementsov-Ogievskiy wrote:
Now, when thread can do negotiation and retry, it may run relatively
long. We need a mechanism to stop it, when user is not interested in
result anymore. So, on nbd_client_connection_release() let's shutdown
the socked, and do not retry connection if thread is detached.
This kinda answers my question to the previous patch about reconnect
cancellation.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
nbd/client-connection.c | 36 ++++++++++++++++++++++++++----------
1 file changed, 26 insertions(+), 10 deletions(-)
diff --git a/nbd/client-connection.c b/nbd/client-connection.c
index 002bd91f42..54f73c6c24 100644
--- a/nbd/client-connection.c
+++ b/nbd/client-connection.c
@@ -158,9 +158,13 @@ static void *connect_thread_func(void *opaque)
uint64_t timeout = 1;
uint64_t max_timeout = 16;
- while (true) {
+ qemu_mutex_lock(&conn->mutex);
+ while (!conn->detached) {
+ assert(!conn->sioc);
conn->sioc = qio_channel_socket_new();
+ qemu_mutex_unlock(&conn->mutex);
+
error_free(conn->err);
conn->err = NULL;
conn->updated_info = conn->initial_info;
@@ -171,14 +175,20 @@ static void *connect_thread_func(void *opaque)
conn->updated_info.x_dirty_bitmap = NULL;
conn->updated_info.name = NULL;
+ qemu_mutex_lock(&conn->mutex);
+
if (ret < 0) {
object_unref(OBJECT(conn->sioc));
conn->sioc = NULL;
- if (conn->do_retry) {
+ if (conn->do_retry && !conn->detached) {
+ qemu_mutex_unlock(&conn->mutex);
+
sleep(timeout);
if (timeout < max_timeout) {
timeout *= 2;
}
+
+ qemu_mutex_lock(&conn->mutex);
continue;
}
}
@@ -186,15 +196,17 @@ static void *connect_thread_func(void *opaque)
break;
}
- WITH_QEMU_LOCK_GUARD(&conn->mutex) {
- assert(conn->running);
- conn->running = false;
- if (conn->wait_co) {
- aio_co_schedule(NULL, conn->wait_co);
- conn->wait_co = NULL;
- }
- do_free = conn->detached;
+ /* mutex is locked */
+
+ assert(conn->running);
+ conn->running = false;
+ if (conn->wait_co) {
+ aio_co_schedule(NULL, conn->wait_co);
+ conn->wait_co = NULL;
}
+ do_free = conn->detached;
+
+ qemu_mutex_unlock(&conn->mutex);
This basically reverts some hunks from patch 15 "nbd/client-connection:
use QEMU_LOCK_GUARD". How about dropping them there (they weren't an
obvious improvement even then).