hw/rdma: Replace QList by GQueue

RdmaProtectedQList provides a thread-safe queue of int64_t on top of a
QList.

rdma_protected_qlist_destroy() calls qlist_destroy_obj() directly.
qlist_destroy_obj() is actually for use by qobject_destroy() only.
The next commit will make that obvious.

The minimal fix would be calling qobject_unref() instead.  But QList
is actually a bad fit here.  It's designed for representing JSON
arrays.  We're better off with a GQueue here.  Replace.

Cc: Yuval Shaia <yuval.shaia.ml@gmail.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-8-armbru@redhat.com>

4 files changed, 30 insertions, 26 deletions

diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c
index 5de010b1fa..6dcdfbbbe2 100644
--- a/hw/rdma/rdma_backend.c
+++ b/hw/rdma/rdma_backend.c
@@ -78,7 +78,7 @@ static void clean_recv_mads(RdmaBackendDev *backend_dev)
     unsigned long cqe_ctx_id;
 
     do {
-        cqe_ctx_id = rdma_protected_qlist_pop_int64(&backend_dev->
+        cqe_ctx_id = rdma_protected_gqueue_pop_int64(&backend_dev->
                                                     recv_mads_list);
         if (cqe_ctx_id != -ENOENT) {
             qatomic_inc(&backend_dev->rdma_dev_res->stats.missing_cqe);
@@ -597,7 +597,7 @@ static unsigned int save_mad_recv_buffer(RdmaBackendDev *backend_dev,
     bctx->up_ctx = ctx;
     bctx->sge = *sge;
 
-    rdma_protected_qlist_append_int64(&backend_dev->recv_mads_list, bctx_id);
+    rdma_protected_gqueue_append_int64(&backend_dev->recv_mads_list, bctx_id);
 
     return 0;
 }
@@ -1111,7 +1111,7 @@ static void process_incoming_mad_req(RdmaBackendDev *backend_dev,
 
     trace_mad_message("recv", msg->umad.mad, msg->umad_len);
 
-    cqe_ctx_id = rdma_protected_qlist_pop_int64(&backend_dev->recv_mads_list);
+    cqe_ctx_id = rdma_protected_gqueue_pop_int64(&backend_dev->recv_mads_list);
     if (cqe_ctx_id == -ENOENT) {
         rdma_warn_report("No more free MADs buffers, waiting for a while");
         sleep(THR_POLL_TO);
@@ -1185,7 +1185,7 @@ static int mad_init(RdmaBackendDev *backend_dev, CharBackend *mad_chr_be)
         return -EIO;
     }
 
-    rdma_protected_qlist_init(&backend_dev->recv_mads_list);
+    rdma_protected_gqueue_init(&backend_dev->recv_mads_list);
 
     enable_rdmacm_mux_async(backend_dev);
 
@@ -1205,7 +1205,7 @@ static void mad_fini(RdmaBackendDev *backend_dev)
 {
     disable_rdmacm_mux_async(backend_dev);
     qemu_chr_fe_disconnect(backend_dev->rdmacm_mux.chr_be);
-    rdma_protected_qlist_destroy(&backend_dev->recv_mads_list);
+    rdma_protected_gqueue_destroy(&backend_dev->recv_mads_list);
 }
 
 int rdma_backend_get_gid_index(RdmaBackendDev *backend_dev,
diff --git a/hw/rdma/rdma_backend_defs.h b/hw/rdma/rdma_backend_defs.h
index 0b55be3503..4e6c0ad695 100644
--- a/hw/rdma/rdma_backend_defs.h
+++ b/hw/rdma/rdma_backend_defs.h
@@ -43,7 +43,7 @@ typedef struct RdmaBackendDev {
     struct ibv_context *context;
     struct ibv_comp_channel *channel;
     uint8_t port_num;
-    RdmaProtectedQList recv_mads_list;
+    RdmaProtectedGQueue recv_mads_list;
     RdmaCmMux rdmacm_mux;
 } RdmaBackendDev;
 
diff --git a/hw/rdma/rdma_utils.c b/hw/rdma/rdma_utils.c
index 698ed4716c..98df58f689 100644
--- a/hw/rdma/rdma_utils.c
+++ b/hw/rdma/rdma_utils.c
@@ -14,8 +14,6 @@
  */
 
 #include "qemu/osdep.h"
-#include "qapi/qmp/qlist.h"
-#include "qapi/qmp/qnum.h"
 #include "trace.h"
 #include "rdma_utils.h"
 
@@ -54,41 +52,46 @@ void rdma_pci_dma_unmap(PCIDevice *dev, void *buffer, dma_addr_t len)
     }
 }
 
-void rdma_protected_qlist_init(RdmaProtectedQList *list)
+void rdma_protected_gqueue_init(RdmaProtectedGQueue *list)
 {
     qemu_mutex_init(&list->lock);
-    list->list = qlist_new();
+    list->list = g_queue_new();
 }
 
-void rdma_protected_qlist_destroy(RdmaProtectedQList *list)
+void rdma_protected_gqueue_destroy(RdmaProtectedGQueue *list)
 {
     if (list->list) {
-        qlist_destroy_obj(QOBJECT(list->list));
+        g_queue_free_full(list->list, g_free);
         qemu_mutex_destroy(&list->lock);
         list->list = NULL;
     }
 }
 
-void rdma_protected_qlist_append_int64(RdmaProtectedQList *list, int64_t value)
+void rdma_protected_gqueue_append_int64(RdmaProtectedGQueue *list,
+                                        int64_t value)
 {
     qemu_mutex_lock(&list->lock);
-    qlist_append_int(list->list, value);
+    g_queue_push_tail(list->list, g_memdup(&value, sizeof(value)));
     qemu_mutex_unlock(&list->lock);
 }
 
-int64_t rdma_protected_qlist_pop_int64(RdmaProtectedQList *list)
+int64_t rdma_protected_gqueue_pop_int64(RdmaProtectedGQueue *list)
 {
-    QObject *obj;
+    int64_t *valp;
+    int64_t val;
 
     qemu_mutex_lock(&list->lock);
-    obj = qlist_pop(list->list);
+
+    valp = g_queue_pop_head(list->list);
     qemu_mutex_unlock(&list->lock);
 
-    if (!obj) {
+    if (!valp) {
         return -ENOENT;
     }
 
-    return qnum_get_uint(qobject_to(QNum, obj));
+    val = *valp;
+    g_free(valp);
+    return val;
 }
 
 void rdma_protected_gslist_init(RdmaProtectedGSList *list)
diff --git a/hw/rdma/rdma_utils.h b/hw/rdma/rdma_utils.h
index e7babe96cb..9fd0efd940 100644
--- a/hw/rdma/rdma_utils.h
+++ b/hw/rdma/rdma_utils.h
@@ -28,10 +28,10 @@
 #define rdma_info_report(fmt, ...) \
     info_report("%s: " fmt, "rdma", ## __VA_ARGS__)
 
-typedef struct RdmaProtectedQList {
+typedef struct RdmaProtectedGQueue {
     QemuMutex lock;
-    QList *list;
-} RdmaProtectedQList;
+    GQueue *list;
+} RdmaProtectedGQueue;
 
 typedef struct RdmaProtectedGSList {
     QemuMutex lock;
@@ -40,10 +40,11 @@ typedef struct RdmaProtectedGSList {
 
 void *rdma_pci_dma_map(PCIDevice *dev, dma_addr_t addr, dma_addr_t plen);
 void rdma_pci_dma_unmap(PCIDevice *dev, void *buffer, dma_addr_t len);
-void rdma_protected_qlist_init(RdmaProtectedQList *list);
-void rdma_protected_qlist_destroy(RdmaProtectedQList *list);
-void rdma_protected_qlist_append_int64(RdmaProtectedQList *list, int64_t value);
-int64_t rdma_protected_qlist_pop_int64(RdmaProtectedQList *list);
+void rdma_protected_gqueue_init(RdmaProtectedGQueue *list);
+void rdma_protected_gqueue_destroy(RdmaProtectedGQueue *list);
+void rdma_protected_gqueue_append_int64(RdmaProtectedGQueue *list,
+                                        int64_t value);
+int64_t rdma_protected_gqueue_pop_int64(RdmaProtectedGQueue *list);
 void rdma_protected_gslist_init(RdmaProtectedGSList *list);
 void rdma_protected_gslist_destroy(RdmaProtectedGSList *list);
 void rdma_protected_gslist_append_int32(RdmaProtectedGSList *list,