Commit e1adb27a authored by Stefan Hajnoczi's avatar Stefan Hajnoczi
Browse files

nbd: use g_slice_new() instead of a freelist 



Use GLib's efficient slice allocator instead of open-coding the request
freelist.  This patch simplifies the NBDRequest code.

Now we qemu_blockalign() the req->data buffer each time but the next
patch switches from a fixed size buffer to a dynamic size anyway.

Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 50522d96

nbd.c

+6 −17
Original line number Diff line number Diff line
@@ -98,7 +98,6 @@ struct NBDExport { 
    off_t size;

    uint32_t nbdflags;

    QTAILQ_HEAD(, NBDClient) clients;

    QSIMPLEQ_HEAD(, NBDRequest) requests;

    QTAILQ_ENTRY(NBDExport) next;

};
@@ -850,13 +849,8 @@ static NBDRequest *nbd_request_get(NBDClient *client) 
    assert(client->nb_requests <= MAX_NBD_REQUESTS - 1);

    client->nb_requests++;



    if (QSIMPLEQ_EMPTY(&exp->requests)) {

        req = g_malloc0(sizeof(NBDRequest));

    req = g_slice_new0(NBDRequest);

    req->data = qemu_blockalign(exp->bs, NBD_BUFFER_SIZE);

    } else {

        req = QSIMPLEQ_FIRST(&exp->requests);

        QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry);

    }

    nbd_client_get(client);

    req->client = client;

    return req;
@@ -865,7 +859,10 @@ static NBDRequest *nbd_request_get(NBDClient *client) 
static void nbd_request_put(NBDRequest *req)

{

    NBDClient *client = req->client;

    QSIMPLEQ_INSERT_HEAD(&client->exp->requests, req, entry);



    qemu_vfree(req->data);

    g_slice_free(NBDRequest, req);



    if (client->nb_requests-- == MAX_NBD_REQUESTS) {

        qemu_notify_event();

    }
@@ -877,7 +874,6 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, 
                          void (*close)(NBDExport *))

{

    NBDExport *exp = g_malloc0(sizeof(NBDExport));

    QSIMPLEQ_INIT(&exp->requests);

    exp->refcount = 1;

    QTAILQ_INIT(&exp->clients);

    exp->bs = bs;
@@ -953,13 +949,6 @@ void nbd_export_put(NBDExport *exp) 
            exp->close(exp);

        }



        while (!QSIMPLEQ_EMPTY(&exp->requests)) {

            NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests);

            QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry);

            qemu_vfree(first->data);

            g_free(first);

        }



        g_free(exp);

    }

}