diff mbox series

[02/10] hw/rdma: Introduce locked qlist

Message ID 20190131130850.6850-3-yuval.shaia@oracle.com (mailing list archive)
State New, archived
Headers show
Series Misc fixes to pvrdma device | expand

Commit Message

Yuval Shaia Jan. 31, 2019, 1:08 p.m. UTC 
To make code more readable move handling of locked list to a generic
functions.

Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
---
 hw/rdma/rdma_backend.c      | 20 +++++--------------
 hw/rdma/rdma_backend_defs.h |  8 ++------
 hw/rdma/rdma_utils.c        | 39 +++++++++++++++++++++++++++++++++++++
 hw/rdma/rdma_utils.h        |  9 +++++++++
 4 files changed, 55 insertions(+), 21 deletions(-)

Comments

Marcel Apfelbaum Feb. 7, 2019, 9:05 a.m. UTC | #1 
Hi Yuval,

On 1/31/19 3:08 PM, Yuval Shaia wrote:
> To make code more readable move handling of locked list to a generic
> functions.
>
> Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
> ---
>   hw/rdma/rdma_backend.c      | 20 +++++--------------
>   hw/rdma/rdma_backend_defs.h |  8 ++------
>   hw/rdma/rdma_utils.c        | 39 +++++++++++++++++++++++++++++++++++++
>   hw/rdma/rdma_utils.h        |  9 +++++++++
>   4 files changed, 55 insertions(+), 21 deletions(-)
>
> diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c
> index 5f60856d19..2f6372f8f0 100644
> --- a/hw/rdma/rdma_backend.c
> +++ b/hw/rdma/rdma_backend.c
> @@ -527,9 +527,7 @@ static unsigned int save_mad_recv_buffer(RdmaBackendDev *backend_dev,
>       bctx->up_ctx = ctx;
>       bctx->sge = *sge;
>   
> -    qemu_mutex_lock(&backend_dev->recv_mads_list.lock);
> -    qlist_append_int(backend_dev->recv_mads_list.list, bctx_id);
> -    qemu_mutex_unlock(&backend_dev->recv_mads_list.lock);
> +    rdma_locked_list_append_int64(&backend_dev->recv_mads_list, bctx_id);
>   
>       return 0;
>   }
> @@ -913,23 +911,19 @@ static inline void build_mad_hdr(struct ibv_grh *grh, union ibv_gid *sgid,
>   static void process_incoming_mad_req(RdmaBackendDev *backend_dev,
>                                        RdmaCmMuxMsg *msg)
>   {
> -    QObject *o_ctx_id;
>       unsigned long cqe_ctx_id;
>       BackendCtx *bctx;
>       char *mad;
>   
>       trace_mad_message("recv", msg->umad.mad, msg->umad_len);
>   
> -    qemu_mutex_lock(&backend_dev->recv_mads_list.lock);
> -    o_ctx_id = qlist_pop(backend_dev->recv_mads_list.list);
> -    qemu_mutex_unlock(&backend_dev->recv_mads_list.lock);
> -    if (!o_ctx_id) {
> +    cqe_ctx_id = rdma_locked_list_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);
>           return;
>       }
>   
> -    cqe_ctx_id = qnum_get_uint(qobject_to(QNum, o_ctx_id));
>       bctx = rdma_rm_get_cqe_ctx(backend_dev->rdma_dev_res, cqe_ctx_id);
>       if (unlikely(!bctx)) {
>           rdma_error_report("No matching ctx for req %ld", cqe_ctx_id);
> @@ -994,8 +988,7 @@ static int mad_init(RdmaBackendDev *backend_dev, CharBackend *mad_chr_be)
>           return -EIO;
>       }
>   
> -    qemu_mutex_init(&backend_dev->recv_mads_list.lock);
> -    backend_dev->recv_mads_list.list = qlist_new();
> +    rdma_locked_list_init(&backend_dev->recv_mads_list);
>   
>       enable_rdmacm_mux_async(backend_dev);
>   
> @@ -1010,10 +1003,7 @@ static void mad_fini(RdmaBackendDev *backend_dev)
>   {
>       disable_rdmacm_mux_async(backend_dev);
>       qemu_chr_fe_disconnect(backend_dev->rdmacm_mux.chr_be);
> -    if (backend_dev->recv_mads_list.list) {
> -        qlist_destroy_obj(QOBJECT(backend_dev->recv_mads_list.list));
> -        qemu_mutex_destroy(&backend_dev->recv_mads_list.lock);
> -    }
> +    rdma_locked_list_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 15ae8b970e..bec0457f25 100644
> --- a/hw/rdma/rdma_backend_defs.h
> +++ b/hw/rdma/rdma_backend_defs.h
> @@ -20,6 +20,7 @@
>   #include "chardev/char-fe.h"
>   #include <infiniband/verbs.h>
>   #include "contrib/rdmacm-mux/rdmacm-mux.h"
> +#include "rdma_utils.h"
>   
>   typedef struct RdmaDeviceResources RdmaDeviceResources;
>   
> @@ -30,11 +31,6 @@ typedef struct RdmaBackendThread {
>       bool is_running; /* Set by the thread to report its status */
>   } RdmaBackendThread;
>   
> -typedef struct RecvMadList {
> -    QemuMutex lock;
> -    QList *list;
> -} RecvMadList;
> -
>   typedef struct RdmaCmMux {
>       CharBackend *chr_be;
>       int can_receive;
> @@ -48,7 +44,7 @@ typedef struct RdmaBackendDev {
>       struct ibv_context *context;
>       struct ibv_comp_channel *channel;
>       uint8_t port_num;
> -    RecvMadList recv_mads_list;
> +    LockedList recv_mads_list;
>       RdmaCmMux rdmacm_mux;
>   } RdmaBackendDev;
>   
> diff --git a/hw/rdma/rdma_utils.c b/hw/rdma/rdma_utils.c
> index f1c980c6be..a2a4ea2a15 100644
> --- a/hw/rdma/rdma_utils.c
> +++ b/hw/rdma/rdma_utils.c
> @@ -14,6 +14,8 @@
>    */
>   
>   #include "qemu/osdep.h"
> +#include "qapi/qmp/qlist.h"
> +#include "qapi/qmp/qnum.h"
>   #include "trace.h"
>   #include "rdma_utils.h"
>   
> @@ -55,3 +57,40 @@ void rdma_pci_dma_unmap(PCIDevice *dev, void *buffer, dma_addr_t len)
>           pci_dma_unmap(dev, buffer, len, DMA_DIRECTION_TO_DEVICE, 0);
>       }
>   }
> +
> +void rdma_locked_list_init(LockedList *list)
> +{
> +    qemu_mutex_init(&list->lock);
> +    list->list = qlist_new();
> +}
> +
> +void rdma_locked_list_destroy(LockedList *list)
> +{
> +    if (list->list) {
> +        qlist_destroy_obj(QOBJECT(list->list));
> +        qemu_mutex_destroy(&list->lock);
> +        list->list = NULL;
> +    }
> +}
> +
> +void rdma_locked_list_append_int64(LockedList *list, int64_t value)
> +{
> +    qemu_mutex_lock(&list->lock);
> +    qlist_append_int(list->list, value);
> +    qemu_mutex_unlock(&list->lock);
> +}
> +
> +int64_t rdma_locked_list_pop_int64(LockedList *list)
> +{
> +    QObject *obj;
> +
> +    qemu_mutex_lock(&list->lock);
> +    obj = qlist_pop(list->list);
> +    qemu_mutex_unlock(&list->lock);
> +
> +    if (!obj) {
> +        return -ENOENT;
> +    }
> +
> +    return qnum_get_uint(qobject_to(QNum, obj));
> +}
> diff --git a/hw/rdma/rdma_utils.h b/hw/rdma/rdma_utils.h
> index acd148837f..4ba9956f81 100644
> --- a/hw/rdma/rdma_utils.h
> +++ b/hw/rdma/rdma_utils.h
> @@ -29,8 +29,17 @@
>   #define rdma_info_report(fmt, ...) \
>       info_report("%s: " fmt, "rdma", ## __VA_ARGS__)
>   
> +typedef struct LockedList {

The naming is a little off, maybe SynchronizedList ?

The more pressing issue, it doesn't seem this code is related to RDMA.
Does anybody think we should move this code to more appropriate place?

Thanks,
Marcel

> +    QemuMutex lock;
> +    QList *list;
> +} LockedList;




> +
>   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_locked_list_init(LockedList *list);
> +void rdma_locked_list_destroy(LockedList *list);
> +void rdma_locked_list_append_int64(LockedList *list, int64_t value);
> +int64_t rdma_locked_list_pop_int64(LockedList *list);
>   
>   static inline void addrconf_addr_eui48(uint8_t *eui, const char *addr)
>   {
Yuval Shaia Feb. 7, 2019, 10:28 a.m. UTC | #2 
On Thu, Feb 07, 2019 at 11:05:23AM +0200, Marcel Apfelbaum wrote:
> Hi Yuval,
> 
> On 1/31/19 3:08 PM, Yuval Shaia wrote:
> > To make code more readable move handling of locked list to a generic
> > functions.
> > 
> > Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
> > ---
> >   hw/rdma/rdma_backend.c      | 20 +++++--------------
> >   hw/rdma/rdma_backend_defs.h |  8 ++------
> >   hw/rdma/rdma_utils.c        | 39 +++++++++++++++++++++++++++++++++++++
> >   hw/rdma/rdma_utils.h        |  9 +++++++++
> >   4 files changed, 55 insertions(+), 21 deletions(-)
> > 
> > diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c
> > index 5f60856d19..2f6372f8f0 100644
> > --- a/hw/rdma/rdma_backend.c
> > +++ b/hw/rdma/rdma_backend.c
> > @@ -527,9 +527,7 @@ static unsigned int save_mad_recv_buffer(RdmaBackendDev *backend_dev,
> >       bctx->up_ctx = ctx;
> >       bctx->sge = *sge;
> > -    qemu_mutex_lock(&backend_dev->recv_mads_list.lock);
> > -    qlist_append_int(backend_dev->recv_mads_list.list, bctx_id);
> > -    qemu_mutex_unlock(&backend_dev->recv_mads_list.lock);
> > +    rdma_locked_list_append_int64(&backend_dev->recv_mads_list, bctx_id);
> >       return 0;
> >   }
> > @@ -913,23 +911,19 @@ static inline void build_mad_hdr(struct ibv_grh *grh, union ibv_gid *sgid,
> >   static void process_incoming_mad_req(RdmaBackendDev *backend_dev,
> >                                        RdmaCmMuxMsg *msg)
> >   {
> > -    QObject *o_ctx_id;
> >       unsigned long cqe_ctx_id;
> >       BackendCtx *bctx;
> >       char *mad;
> >       trace_mad_message("recv", msg->umad.mad, msg->umad_len);
> > -    qemu_mutex_lock(&backend_dev->recv_mads_list.lock);
> > -    o_ctx_id = qlist_pop(backend_dev->recv_mads_list.list);
> > -    qemu_mutex_unlock(&backend_dev->recv_mads_list.lock);
> > -    if (!o_ctx_id) {
> > +    cqe_ctx_id = rdma_locked_list_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);
> >           return;
> >       }
> > -    cqe_ctx_id = qnum_get_uint(qobject_to(QNum, o_ctx_id));
> >       bctx = rdma_rm_get_cqe_ctx(backend_dev->rdma_dev_res, cqe_ctx_id);
> >       if (unlikely(!bctx)) {
> >           rdma_error_report("No matching ctx for req %ld", cqe_ctx_id);
> > @@ -994,8 +988,7 @@ static int mad_init(RdmaBackendDev *backend_dev, CharBackend *mad_chr_be)
> >           return -EIO;
> >       }
> > -    qemu_mutex_init(&backend_dev->recv_mads_list.lock);
> > -    backend_dev->recv_mads_list.list = qlist_new();
> > +    rdma_locked_list_init(&backend_dev->recv_mads_list);
> >       enable_rdmacm_mux_async(backend_dev);
> > @@ -1010,10 +1003,7 @@ static void mad_fini(RdmaBackendDev *backend_dev)
> >   {
> >       disable_rdmacm_mux_async(backend_dev);
> >       qemu_chr_fe_disconnect(backend_dev->rdmacm_mux.chr_be);
> > -    if (backend_dev->recv_mads_list.list) {
> > -        qlist_destroy_obj(QOBJECT(backend_dev->recv_mads_list.list));
> > -        qemu_mutex_destroy(&backend_dev->recv_mads_list.lock);
> > -    }
> > +    rdma_locked_list_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 15ae8b970e..bec0457f25 100644
> > --- a/hw/rdma/rdma_backend_defs.h
> > +++ b/hw/rdma/rdma_backend_defs.h
> > @@ -20,6 +20,7 @@
> >   #include "chardev/char-fe.h"
> >   #include <infiniband/verbs.h>
> >   #include "contrib/rdmacm-mux/rdmacm-mux.h"
> > +#include "rdma_utils.h"
> >   typedef struct RdmaDeviceResources RdmaDeviceResources;
> > @@ -30,11 +31,6 @@ typedef struct RdmaBackendThread {
> >       bool is_running; /* Set by the thread to report its status */
> >   } RdmaBackendThread;
> > -typedef struct RecvMadList {
> > -    QemuMutex lock;
> > -    QList *list;
> > -} RecvMadList;
> > -
> >   typedef struct RdmaCmMux {
> >       CharBackend *chr_be;
> >       int can_receive;
> > @@ -48,7 +44,7 @@ typedef struct RdmaBackendDev {
> >       struct ibv_context *context;
> >       struct ibv_comp_channel *channel;
> >       uint8_t port_num;
> > -    RecvMadList recv_mads_list;
> > +    LockedList recv_mads_list;
> >       RdmaCmMux rdmacm_mux;
> >   } RdmaBackendDev;
> > diff --git a/hw/rdma/rdma_utils.c b/hw/rdma/rdma_utils.c
> > index f1c980c6be..a2a4ea2a15 100644
> > --- a/hw/rdma/rdma_utils.c
> > +++ b/hw/rdma/rdma_utils.c
> > @@ -14,6 +14,8 @@
> >    */
> >   #include "qemu/osdep.h"
> > +#include "qapi/qmp/qlist.h"
> > +#include "qapi/qmp/qnum.h"
> >   #include "trace.h"
> >   #include "rdma_utils.h"
> > @@ -55,3 +57,40 @@ void rdma_pci_dma_unmap(PCIDevice *dev, void *buffer, dma_addr_t len)
> >           pci_dma_unmap(dev, buffer, len, DMA_DIRECTION_TO_DEVICE, 0);
> >       }
> >   }
> > +
> > +void rdma_locked_list_init(LockedList *list)
> > +{
> > +    qemu_mutex_init(&list->lock);
> > +    list->list = qlist_new();
> > +}
> > +
> > +void rdma_locked_list_destroy(LockedList *list)
> > +{
> > +    if (list->list) {
> > +        qlist_destroy_obj(QOBJECT(list->list));
> > +        qemu_mutex_destroy(&list->lock);
> > +        list->list = NULL;
> > +    }
> > +}
> > +
> > +void rdma_locked_list_append_int64(LockedList *list, int64_t value)
> > +{
> > +    qemu_mutex_lock(&list->lock);
> > +    qlist_append_int(list->list, value);
> > +    qemu_mutex_unlock(&list->lock);
> > +}
> > +
> > +int64_t rdma_locked_list_pop_int64(LockedList *list)
> > +{
> > +    QObject *obj;
> > +
> > +    qemu_mutex_lock(&list->lock);
> > +    obj = qlist_pop(list->list);
> > +    qemu_mutex_unlock(&list->lock);
> > +
> > +    if (!obj) {
> > +        return -ENOENT;
> > +    }
> > +
> > +    return qnum_get_uint(qobject_to(QNum, obj));
> > +}
> > diff --git a/hw/rdma/rdma_utils.h b/hw/rdma/rdma_utils.h
> > index acd148837f..4ba9956f81 100644
> > --- a/hw/rdma/rdma_utils.h
> > +++ b/hw/rdma/rdma_utils.h
> > @@ -29,8 +29,17 @@
> >   #define rdma_info_report(fmt, ...) \
> >       info_report("%s: " fmt, "rdma", ## __VA_ARGS__)
> > +typedef struct LockedList {
> 
> The naming is a little off, maybe SynchronizedList ?

I believe it will break amending the other patches in this patchset so just
in case this makes a huge different i will consider to change.

> 
> The more pressing issue, it doesn't seem this code is related to RDMA.
> Does anybody think we should move this code to more appropriate place?

Well, i gathered several "general" utilities in rdma_utils.h. In case they
are needed in some other places i will be glad to relocate them.

> 
> Thanks,
> Marcel
> 
> > +    QemuMutex lock;
> > +    QList *list;
> > +} LockedList;
> 
> 
> 
> 
> > +
> >   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_locked_list_init(LockedList *list);
> > +void rdma_locked_list_destroy(LockedList *list);
> > +void rdma_locked_list_append_int64(LockedList *list, int64_t value);
> > +int64_t rdma_locked_list_pop_int64(LockedList *list);
> >   static inline void addrconf_addr_eui48(uint8_t *eui, const char *addr)
> >   {
> 
>
diff mbox series

Patch

diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c
index 5f60856d19..2f6372f8f0 100644
--- a/hw/rdma/rdma_backend.c
+++ b/hw/rdma/rdma_backend.c
@@ -527,9 +527,7 @@  static unsigned int save_mad_recv_buffer(RdmaBackendDev *backend_dev,
     bctx->up_ctx = ctx;
     bctx->sge = *sge;
 
-    qemu_mutex_lock(&backend_dev->recv_mads_list.lock);
-    qlist_append_int(backend_dev->recv_mads_list.list, bctx_id);
-    qemu_mutex_unlock(&backend_dev->recv_mads_list.lock);
+    rdma_locked_list_append_int64(&backend_dev->recv_mads_list, bctx_id);
 
     return 0;
 }
@@ -913,23 +911,19 @@  static inline void build_mad_hdr(struct ibv_grh *grh, union ibv_gid *sgid,
 static void process_incoming_mad_req(RdmaBackendDev *backend_dev,
                                      RdmaCmMuxMsg *msg)
 {
-    QObject *o_ctx_id;
     unsigned long cqe_ctx_id;
     BackendCtx *bctx;
     char *mad;
 
     trace_mad_message("recv", msg->umad.mad, msg->umad_len);
 
-    qemu_mutex_lock(&backend_dev->recv_mads_list.lock);
-    o_ctx_id = qlist_pop(backend_dev->recv_mads_list.list);
-    qemu_mutex_unlock(&backend_dev->recv_mads_list.lock);
-    if (!o_ctx_id) {
+    cqe_ctx_id = rdma_locked_list_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);
         return;
     }
 
-    cqe_ctx_id = qnum_get_uint(qobject_to(QNum, o_ctx_id));
     bctx = rdma_rm_get_cqe_ctx(backend_dev->rdma_dev_res, cqe_ctx_id);
     if (unlikely(!bctx)) {
         rdma_error_report("No matching ctx for req %ld", cqe_ctx_id);
@@ -994,8 +988,7 @@  static int mad_init(RdmaBackendDev *backend_dev, CharBackend *mad_chr_be)
         return -EIO;
     }
 
-    qemu_mutex_init(&backend_dev->recv_mads_list.lock);
-    backend_dev->recv_mads_list.list = qlist_new();
+    rdma_locked_list_init(&backend_dev->recv_mads_list);
 
     enable_rdmacm_mux_async(backend_dev);
 
@@ -1010,10 +1003,7 @@  static void mad_fini(RdmaBackendDev *backend_dev)
 {
     disable_rdmacm_mux_async(backend_dev);
     qemu_chr_fe_disconnect(backend_dev->rdmacm_mux.chr_be);
-    if (backend_dev->recv_mads_list.list) {
-        qlist_destroy_obj(QOBJECT(backend_dev->recv_mads_list.list));
-        qemu_mutex_destroy(&backend_dev->recv_mads_list.lock);
-    }
+    rdma_locked_list_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 15ae8b970e..bec0457f25 100644
--- a/hw/rdma/rdma_backend_defs.h
+++ b/hw/rdma/rdma_backend_defs.h
@@ -20,6 +20,7 @@ 
 #include "chardev/char-fe.h"
 #include <infiniband/verbs.h>
 #include "contrib/rdmacm-mux/rdmacm-mux.h"
+#include "rdma_utils.h"
 
 typedef struct RdmaDeviceResources RdmaDeviceResources;
 
@@ -30,11 +31,6 @@  typedef struct RdmaBackendThread {
     bool is_running; /* Set by the thread to report its status */
 } RdmaBackendThread;
 
-typedef struct RecvMadList {
-    QemuMutex lock;
-    QList *list;
-} RecvMadList;
-
 typedef struct RdmaCmMux {
     CharBackend *chr_be;
     int can_receive;
@@ -48,7 +44,7 @@  typedef struct RdmaBackendDev {
     struct ibv_context *context;
     struct ibv_comp_channel *channel;
     uint8_t port_num;
-    RecvMadList recv_mads_list;
+    LockedList recv_mads_list;
     RdmaCmMux rdmacm_mux;
 } RdmaBackendDev;
 
diff --git a/hw/rdma/rdma_utils.c b/hw/rdma/rdma_utils.c
index f1c980c6be..a2a4ea2a15 100644
--- a/hw/rdma/rdma_utils.c
+++ b/hw/rdma/rdma_utils.c
@@ -14,6 +14,8 @@ 
  */
 
 #include "qemu/osdep.h"
+#include "qapi/qmp/qlist.h"
+#include "qapi/qmp/qnum.h"
 #include "trace.h"
 #include "rdma_utils.h"
 
@@ -55,3 +57,40 @@  void rdma_pci_dma_unmap(PCIDevice *dev, void *buffer, dma_addr_t len)
         pci_dma_unmap(dev, buffer, len, DMA_DIRECTION_TO_DEVICE, 0);
     }
 }
+
+void rdma_locked_list_init(LockedList *list)
+{
+    qemu_mutex_init(&list->lock);
+    list->list = qlist_new();
+}
+
+void rdma_locked_list_destroy(LockedList *list)
+{
+    if (list->list) {
+        qlist_destroy_obj(QOBJECT(list->list));
+        qemu_mutex_destroy(&list->lock);
+        list->list = NULL;
+    }
+}
+
+void rdma_locked_list_append_int64(LockedList *list, int64_t value)
+{
+    qemu_mutex_lock(&list->lock);
+    qlist_append_int(list->list, value);
+    qemu_mutex_unlock(&list->lock);
+}
+
+int64_t rdma_locked_list_pop_int64(LockedList *list)
+{
+    QObject *obj;
+
+    qemu_mutex_lock(&list->lock);
+    obj = qlist_pop(list->list);
+    qemu_mutex_unlock(&list->lock);
+
+    if (!obj) {
+        return -ENOENT;
+    }
+
+    return qnum_get_uint(qobject_to(QNum, obj));
+}
diff --git a/hw/rdma/rdma_utils.h b/hw/rdma/rdma_utils.h
index acd148837f..4ba9956f81 100644
--- a/hw/rdma/rdma_utils.h
+++ b/hw/rdma/rdma_utils.h
@@ -29,8 +29,17 @@ 
 #define rdma_info_report(fmt, ...) \
     info_report("%s: " fmt, "rdma", ## __VA_ARGS__)
 
+typedef struct LockedList {
+    QemuMutex lock;
+    QList *list;
+} LockedList;
+
 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_locked_list_init(LockedList *list);
+void rdma_locked_list_destroy(LockedList *list);
+void rdma_locked_list_append_int64(LockedList *list, int64_t value);
+int64_t rdma_locked_list_pop_int64(LockedList *list);
 
 static inline void addrconf_addr_eui48(uint8_t *eui, const char *addr)
 {