util/vhost-user-server: rename refcount to in_flight counter

The VuServer object has a refcount field and ref/unref APIs. The name is
confusing because it's actually an in-flight request counter instead of
a refcount.

Normally a refcount destroys the object upon reaching zero. The VuServer
counter is used to wake up the vhost-user coroutine when there are no
more requests.

Avoid confusing by renaming refcount and ref/unref to in_flight and
inc/dec.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-6-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2023-05-16 15:02:23 -04:00 committed by Kevin Wolf
parent ca66df878e
commit 75d33e8525
3 changed files with 17 additions and 14 deletions

View File

@ -50,7 +50,10 @@ static void vu_blk_req_complete(VuBlkReq *req, size_t in_len)
free(req);
}
/* Called with server refcount increased, must decrease before returning */
/*
* Called with server in_flight counter increased, must decrease before
* returning.
*/
static void coroutine_fn vu_blk_virtio_process_req(void *opaque)
{
VuBlkReq *req = opaque;
@ -68,12 +71,12 @@ static void coroutine_fn vu_blk_virtio_process_req(void *opaque)
in_num, out_num);
if (in_len < 0) {
free(req);
vhost_user_server_unref(server);
vhost_user_server_dec_in_flight(server);
return;
}
vu_blk_req_complete(req, in_len);
vhost_user_server_unref(server);
vhost_user_server_dec_in_flight(server);
}
static void vu_blk_process_vq(VuDev *vu_dev, int idx)
@ -95,7 +98,7 @@ static void vu_blk_process_vq(VuDev *vu_dev, int idx)
Coroutine *co =
qemu_coroutine_create(vu_blk_virtio_process_req, req);
vhost_user_server_ref(server);
vhost_user_server_inc_in_flight(server);
qemu_coroutine_enter(co);
}
}

View File

@ -41,7 +41,7 @@ typedef struct {
const VuDevIface *vu_iface;
/* Protected by ctx lock */
unsigned int refcount;
unsigned int in_flight;
bool wait_idle;
VuDev vu_dev;
QIOChannel *ioc; /* The I/O channel with the client */
@ -60,8 +60,8 @@ bool vhost_user_server_start(VuServer *server,
void vhost_user_server_stop(VuServer *server);
void vhost_user_server_ref(VuServer *server);
void vhost_user_server_unref(VuServer *server);
void vhost_user_server_inc_in_flight(VuServer *server);
void vhost_user_server_dec_in_flight(VuServer *server);
void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx);
void vhost_user_server_detach_aio_context(VuServer *server);

View File

@ -75,16 +75,16 @@ static void panic_cb(VuDev *vu_dev, const char *buf)
error_report("vu_panic: %s", buf);
}
void vhost_user_server_ref(VuServer *server)
void vhost_user_server_inc_in_flight(VuServer *server)
{
assert(!server->wait_idle);
server->refcount++;
server->in_flight++;
}
void vhost_user_server_unref(VuServer *server)
void vhost_user_server_dec_in_flight(VuServer *server)
{
server->refcount--;
if (server->wait_idle && !server->refcount) {
server->in_flight--;
if (server->wait_idle && !server->in_flight) {
aio_co_wake(server->co_trip);
}
}
@ -192,13 +192,13 @@ static coroutine_fn void vu_client_trip(void *opaque)
/* Keep running */
}
if (server->refcount) {
if (server->in_flight) {
/* Wait for requests to complete before we can unmap the memory */
server->wait_idle = true;
qemu_coroutine_yield();
server->wait_idle = false;
}
assert(server->refcount == 0);
assert(server->in_flight == 0);
vu_deinit(vu_dev);