Re: [Qemu-devel] [Qemu-stable] [PATCH] rdma: fix multiple VMs parallel migration

[Frank Yang <frank.yangjie@gmail.com>]

于 2013-9-25 1:59, Michael R. Hines 写道:
> On 09/04/2013 04:10 AM, Frank Yang wrote:
>>> On 2013-9-3 13:03, Lei Li wrote:
>>>> Hi Frank,
>>>>
>>>> I failed to apply this patch. Please make sure to use 
>>>> git-send-email, otherwise
>>>> it's a little hard to review. :)
>>>>
>>>> On 08/30/2013 08:39 PM, Frank Yang wrote:
>>>>> When several VMs migrate with RDMA at the same time, the increased 
>>>>> pressure cause packet loss probabilistically and make source and 
>>>>> destination wait for each other. There might be some of VMs 
>>>>> blocked during the migration.
>>>>>
>>>>> Fix the bug by using two completion queues, for sending and 
>>>>> receiving respectively.
>>>>> From 0c4829495cdc89eea2e94b103ac42c3f6a4b32c2 Mon Sep 17 00:00:00 
>>>>> 2001
>>>>> From: Frank Yang <frank.yangjie@gmail.com 
>>>>> <mailto:frank.yangjie@gmail.com>>
>>>>> Date: Fri, 30 Aug 2013 17:53:34 +0800
>>>>> Subject: [PATCH] rdma: fix multiple VMs parallel migration
>>>> The commit message should be here within the patch. You can use 
>>>> 'git commit --amend'
>>>> to add it.
>>>>
>>>>> Signed-off-by: Frank Yang <frank.yangjie@gmail.com 
>>>>> <mailto:frank.yangjie@gmail.com>>
>>>>> ---
>>>>> migration-rdma.c | 57 
>>>>> ++++++++++++++++++++++++++++++++++++--------------------
>>>>> 1 file changed, 37 insertions(+), 20 deletions(-)
>>>>>
>>>>> diff --git a/migration-rdma.c b/migration-rdma.c
>>>>> index 3d1266f..d0eacbb 100644
>>>>> --- a/migration-rdma.c
>>>>> +++ b/migration-rdma.c
>>>>> @@ -362,7 +362,8 @@ typedef struct RDMAContext {
>>>>> struct ibv_qp *qp; /* queue pair */
>>>>> struct ibv_comp_channel *comp_channel; /* completion channel */
>>>>> struct ibv_pd *pd; /* protection domain */
>>>>> - struct ibv_cq *cq; /* completion queue */
>>>>> + struct ibv_cq *send_cq; /* send completion queue */
>>>>> + struct ibv_cq *recv_cq; /* receive completion queue */
>>>>> /*
>>>>> * If a previous write failed (perhaps because of a failed
>>>>> @@ -1006,9 +1007,12 @@ static int 
>>>>> qemu_rdma_alloc_pd_cq(RDMAContext *rdma)
>>>>> * Completion queue can be filled by both read and write work 
>>>>> requests,
>>>>> * so must reflect the sum of both possible queue sizes.
>>>>> */
>>>>> - rdma->cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX * 3),
>>>>> + rdma->send_cq = ibv_create_cq(rdma->verbs, 
>>>>> (RDMA_SIGNALED_SEND_MAX * 2),
>>>>> NULL, rdma->comp_channel, 0);
>>>>> - if (!rdma->cq) {
>>>>> + rdma->recv_cq = ibv_create_cq(rdma->verbs, 
>>>>> RDMA_SIGNALED_SEND_MAX, NULL,
>>>>> + rdma->comp_channel, 0);
>>>>> +
>>>>> + if (!rdma->send_cq || !rdma->recv_cq) {
>>>>> fprintf(stderr, "failed to allocate completion queue\n");
>>>>> goto err_alloc_pd_cq;
>>>>> }
>>>>> @@ -1040,8 +1044,8 @@ static int qemu_rdma_alloc_qp(RDMAContext 
>>>>> *rdma)
>>>>> attr.cap.max_recv_wr = 3;
>>>>> attr.cap.max_send_sge = 1;
>>>>> attr.cap.max_recv_sge = 1;
>>>>> - attr.send_cq = rdma->cq;
>>>>> - attr.recv_cq = rdma->cq;
>>>>> + attr.send_cq = rdma->send_cq;
>>>>> + attr.recv_cq = rdma->recv_cq;
>>>>> attr.qp_type = IBV_QPT_RC;
>>>>> ret = rdma_create_qp(rdma->cm_id, rdma->pd, &attr);
>>>>> @@ -1361,13 +1365,18 @@ static void 
>>>>> qemu_rdma_signal_unregister(RDMAContext *rdma, uint64_t index,
>>>>> * Return the work request ID that completed.
>>>>> */
>>>>> static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t 
>>>>> *wr_id_out,
>>>>> - uint32_t *byte_len)
>>>>> + uint32_t *byte_len, int wrid_requested)
>>>>> {
>>>>> int ret;
>>>>> struct ibv_wc wc;
>>>>> uint64_t wr_id;
>>>>> - ret = ibv_poll_cq(rdma->cq, 1, &wc);
>>>>> + if (wrid_requested == RDMA_WRID_RDMA_WRITE ||
>>>>> + wrid_requested == RDMA_WRID_SEND_CONTROL) {
>>>>> + ret = ibv_poll_cq(rdma->send_cq, 1, &wc);
>>>>> + } else if (wrid_requested >= RDMA_WRID_RECV_CONTROL) {
>>>>> + ret = ibv_poll_cq(rdma->recv_cq, 1, &wc);
>>>>> + }
>>>>> if (!ret) {
>>>>> *wr_id_out = RDMA_WRID_NONE;
>>>>> @@ -1460,12 +1469,9 @@ static int 
>>>>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>>>>> void *cq_ctx;
>>>>> uint64_t wr_id = RDMA_WRID_NONE, wr_id_in;
>>>>> - if (ibv_req_notify_cq(rdma->cq, 0)) {
>>>>> - return -1;
>>>>> - }
>>>>> /* poll cq first */
>>>>> while (wr_id != wrid_requested) {
>>>>> - ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
>>>>> + ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len, wrid_requested);
>>>>> if (ret < 0) {
>>>>> return ret;
>>>>> }
>>>>> @@ -1487,6 +1493,17 @@ static int 
>>>>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>>>>> }
>>>>> while (1) {
>>>>> + if (wrid_requested == RDMA_WRID_RDMA_WRITE ||
>>>>> + wrid_requested == RDMA_WRID_SEND_CONTROL) {
>>>>> + if (ibv_req_notify_cq(rdma->send_cq, 0)) {
>>>>> + return -1;
>>>>> + }
>>>>> + } else if (wrid_requested >= RDMA_WRID_RECV_CONTROL) {
>>>>> + if (ibv_req_notify_cq(rdma->recv_cq, 0)) {
>>>>> + return -1;
>>>>> + }
>>>>> + }
>>>>> +
>>>>> /*
>>>>> * Coroutine doesn't start until process_incoming_migration()
>>>>> * so don't yield unless we know we're running inside of a coroutine.
>>>>> @@ -1502,12 +1519,8 @@ static int 
>>>>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>>>>> num_cq_events++;
>>>>> - if (ibv_req_notify_cq(cq, 0)) {
>>>>> - goto err_block_for_wrid;
>>>>> - }
>>>>> -
>>>>> while (wr_id != wrid_requested) {
>>>>> - ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
>>>>> + ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len, wrid_requested);
>>>>> if (ret < 0) {
>>>>> goto err_block_for_wrid;
>>>>> }
>>>>> @@ -2236,9 +2249,13 @@ static void qemu_rdma_cleanup(RDMAContext 
>>>>> *rdma)
>>>>> ibv_destroy_qp(rdma->qp);
>>>>> rdma->qp = NULL;
>>>>> }
>>>>> - if (rdma->cq) {
>>>>> - ibv_destroy_cq(rdma->cq);
>>>>> - rdma->cq = NULL;
>>>>> + if (rdma->send_cq) {
>>>>> + ibv_destroy_cq(rdma->send_cq);
>>>>> + rdma->send_cq = NULL;
>>>>> + }
>>>>> + if (rdma->recv_cq) {
>>>>> + ibv_destroy_cq(rdma->recv_cq);
>>>>> + rdma->recv_cq = NULL;
>>>>> }
>>>>> if (rdma->comp_channel) {
>>>>> ibv_destroy_comp_channel(rdma->comp_channel);
>>>>> @@ -2770,7 +2787,7 @@ static size_t qemu_rdma_save_page(QEMUFile 
>>>>> *f, void *opaque,
>>>>> */
>>>>> while (1) {
>>>>> uint64_t wr_id, wr_id_in;
>>>>> - int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL);
>>>>> + int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL, 
>>>>> RDMA_WRID_RDMA_WRITE);
>>>>> if (ret < 0) {
>>>>> fprintf(stderr, "rdma migration: polling error! %d\n", ret);
>>>>> goto err;
>>>>> -- 
>>>>> 1.8.3.msysgit.0
>>>>>
>>>>>
>>>>
>>> Understood. Thank you. The following patch should be fine.
>>>
>>> From 7b7d2c5b51c53c23f7194d35b469dedd892ef89f Mon Sep 17 00:00:00 2001
>>> From: Frank Yang <frank.yangjie@gmail.com>
>>> Date: Tue, 3 Sep 2013 18:26:54 +0800
>>> Subject: [PATCH] rdma: fix multiple VMs parallel migration
>>>
>>> Signed-off-by: Frank Yang <frank.yangjie@gmail.com>
>>> ---
>>> migration-rdma.c | 64 
>>> +++++++++++++++++++++++++++++++++++++-------------------
>>> 1 file changed, 42 insertions(+), 22 deletions(-)
>>>
>>> diff --git a/migration-rdma.c b/migration-rdma.c
>>> index 3d1266f..30f8c11 100644
>>> --- a/migration-rdma.c
>>> +++ b/migration-rdma.c
>>> @@ -362,7 +362,8 @@ typedef struct RDMAContext {
>>> struct ibv_qp *qp; /* queue pair */
>>> struct ibv_comp_channel *comp_channel; /* completion channel */
>>> struct ibv_pd *pd; /* protection domain */
>>> - struct ibv_cq *cq; /* completion queue */
>>> + struct ibv_cq *send_cq; /* send completion queue */
>>> + struct ibv_cq *recv_cq; /* receive completion queue */
>>>
>>> /*
>>> * If a previous write failed (perhaps because of a failed
>>> @@ -1003,12 +1004,18 @@ static int qemu_rdma_alloc_pd_cq(RDMAContext 
>>> *rdma)
>>> }
>>>
>>> /*
>>> - * Completion queue can be filled by both read and write work 
>>> requests,
>>> - * so must reflect the sum of both possible queue sizes.
>>> + * Create two completion queues for sending and receiving
>>> + * respectively.
>>> + * Send completion queue can be filled by both send and
>>> + * write work requests, so must reflect the sum of both
>>> + * possible queue sizes.
>>> */
>>> - rdma->cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX * 3),
>>> + rdma->send_cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX 
>>> * 2),
>>> NULL, rdma->comp_channel, 0);
>>> - if (!rdma->cq) {
>>> + rdma->recv_cq = ibv_create_cq(rdma->verbs, RDMA_SIGNALED_SEND_MAX, 
>>> NULL,
>>> + rdma->comp_channel, 0);
>>> +
>>> + if (!rdma->send_cq || !rdma->recv_cq) {
>>> fprintf(stderr, "failed to allocate completion queue\n");
>>> goto err_alloc_pd_cq;
>>> }
>>> @@ -1040,8 +1047,8 @@ static int qemu_rdma_alloc_qp(RDMAContext *rdma)
>>> attr.cap.max_recv_wr = 3;
>>> attr.cap.max_send_sge = 1;
>>> attr.cap.max_recv_sge = 1;
>>> - attr.send_cq = rdma->cq;
>>> - attr.recv_cq = rdma->cq;
>>> + attr.send_cq = rdma->send_cq;
>>> + attr.recv_cq = rdma->recv_cq;
>>> attr.qp_type = IBV_QPT_RC;
>>>
>>> ret = rdma_create_qp(rdma->cm_id, rdma->pd, &attr);
>>> @@ -1361,13 +1368,18 @@ static void 
>>> qemu_rdma_signal_unregister(RDMAContext *rdma, uint64_t index,
>>> * Return the work request ID that completed.
>>> */
>>> static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out,
>>> - uint32_t *byte_len)
>>> + uint32_t *byte_len, int wrid_requested)
>>> {
>>> int ret;
>>> struct ibv_wc wc;
>>> uint64_t wr_id;
>>>
>>> - ret = ibv_poll_cq(rdma->cq, 1, &wc);
>>> + if (wrid_requested == RDMA_WRID_RDMA_WRITE ||
>>> + wrid_requested == RDMA_WRID_SEND_CONTROL) {
>>> + ret = ibv_poll_cq(rdma->send_cq, 1, &wc);
>>> + } else if (wrid_requested >= RDMA_WRID_RECV_CONTROL) {
>>> + ret = ibv_poll_cq(rdma->recv_cq, 1, &wc);
>>> + }
>>>
>>> if (!ret) {
>>> *wr_id_out = RDMA_WRID_NONE;
>>> @@ -1460,12 +1472,9 @@ static int 
>>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>>> void *cq_ctx;
>>> uint64_t wr_id = RDMA_WRID_NONE, wr_id_in;
>>>
>>> - if (ibv_req_notify_cq(rdma->cq, 0)) {
>>> - return -1;
>>> - }
>>> /* poll cq first */
>>> while (wr_id != wrid_requested) {
>>> - ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
>>> + ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len, wrid_requested);
>>> if (ret < 0) {
>>> return ret;
>>> }
>>> @@ -1487,6 +1496,17 @@ static int 
>>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>>> }
>>>
>>> while (1) {
>>> + if (wrid_requested == RDMA_WRID_RDMA_WRITE ||
>>> + wrid_requested == RDMA_WRID_SEND_CONTROL) {
>>> + if (ibv_req_notify_cq(rdma->send_cq, 0)) {
>>> + return -1;
>>> + }
>>> + } else if (wrid_requested >= RDMA_WRID_RECV_CONTROL) {
>>> + if (ibv_req_notify_cq(rdma->recv_cq, 0)) {
>>> + return -1;
>>> + }
>>> + }
>>> +
>>> /*
>>> * Coroutine doesn't start until process_incoming_migration()
>>> * so don't yield unless we know we're running inside of a coroutine.
>>> @@ -1502,12 +1522,8 @@ static int 
>>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>>>
>>> num_cq_events++;
>>>
>>> - if (ibv_req_notify_cq(cq, 0)) {
>>> - goto err_block_for_wrid;
>>> - }
>>> -
>>> while (wr_id != wrid_requested) {
>>> - ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
>>> + ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len, wrid_requested);
>>> if (ret < 0) {
>>> goto err_block_for_wrid;
>>> }
>>> @@ -2236,9 +2252,13 @@ static void qemu_rdma_cleanup(RDMAContext *rdma)
>>> ibv_destroy_qp(rdma->qp);
>>> rdma->qp = NULL;
>>> }
>>> - if (rdma->cq) {
>>> - ibv_destroy_cq(rdma->cq);
>>> - rdma->cq = NULL;
>>> + if (rdma->send_cq) {
>>> + ibv_destroy_cq(rdma->send_cq);
>>> + rdma->send_cq = NULL;
>>> + }
>>> + if (rdma->recv_cq) {
>>> + ibv_destroy_cq(rdma->recv_cq);
>>> + rdma->recv_cq = NULL;
>>> }
>>> if (rdma->comp_channel) {
>>> ibv_destroy_comp_channel(rdma->comp_channel);
>>> @@ -2770,7 +2790,7 @@ static size_t qemu_rdma_save_page(QEMUFile *f, 
>>> void *opaque,
>>> */
>>> while (1) {
>>> uint64_t wr_id, wr_id_in;
>>> - int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL);
>>> + int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL, 
>>> RDMA_WRID_RDMA_WRITE);
>>> if (ret < 0) {
>>> fprintf(stderr, "rdma migration: polling error! %d\n", ret);
>>> goto err;
>>> -- 
>>> 1.8.3.msysgit.0
>>>
>>>
>>>
>> Sorry, my bad. Please follow this patch:
>>
>> From: Frank Yang <frank.yangjiedd@gmail.com>
>>
>> Signed-off-by: Frank Yang <frank.yangjie@gmail.com>
>> ---
>> migration-rdma.c | 64 
>> +++++++++++++++++++++++++++++++++++++-------------------
>> 1 file changed, 42 insertions(+), 22 deletions(-)
>>
>> diff --git a/migration-rdma.c b/migration-rdma.c
>> index 3d1266f..f3206c4 100644
>> --- a/migration-rdma.c
>> +++ b/migration-rdma.c
>> @@ -362,7 +362,8 @@ typedef struct RDMAContext {
>> struct ibv_qp *qp; /* queue pair */
>> struct ibv_comp_channel *comp_channel; /* completion channel */
>> struct ibv_pd *pd; /* protection domain */
>> - struct ibv_cq *cq; /* completion queue */
>> + struct ibv_cq *send_cq; /* send completion queue */
>> + struct ibv_cq *recv_cq; /* receive completion queue */
>> /*
>> * If a previous write failed (perhaps because of a failed
>> @@ -1003,12 +1004,18 @@ static int qemu_rdma_alloc_pd_cq(RDMAContext 
>> *rdma)
>> }
>> /*
>> - * Completion queue can be filled by both read and write work requests,
>> - * so must reflect the sum of both possible queue sizes.
>> + * Create two completion queues for sending and receiving
>> + * respectively.
>> + * Send completion queue can be filled by both send and
>> + * write work requests, so must reflect the sum of both
>> + * possible queue sizes.
>> */
>> - rdma->cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX * 3),
>> + rdma->send_cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX 
>> * 2),
>> NULL, rdma->comp_channel, 0);
>> - if (!rdma->cq) {
>> + rdma->recv_cq = ibv_create_cq(rdma->verbs, RDMA_SIGNALED_SEND_MAX, 
>> NULL,
>> + rdma->comp_channel, 0);
>> +
>> + if (!rdma->send_cq || !rdma->recv_cq) {
>> fprintf(stderr, "failed to allocate completion queue\n");
>> goto err_alloc_pd_cq;
>> }
>> @@ -1040,8 +1047,8 @@ static int qemu_rdma_alloc_qp(RDMAContext *rdma)
>> attr.cap.max_recv_wr = 3;
>> attr.cap.max_send_sge = 1;
>> attr.cap.max_recv_sge = 1;
>> - attr.send_cq = rdma->cq;
>> - attr.recv_cq = rdma->cq;
>> + attr.send_cq = rdma->send_cq;
>> + attr.recv_cq = rdma->recv_cq;
>> attr.qp_type = IBV_QPT_RC;
>> ret = rdma_create_qp(rdma->cm_id, rdma->pd, &attr);
>> @@ -1361,13 +1368,18 @@ static void 
>> qemu_rdma_signal_unregister(RDMAContext *rdma, uint64_t index,
>> * Return the work request ID that completed.
>> */
>> static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out,
>> - uint32_t *byte_len)
>> + uint32_t *byte_len, int wrid_requested)
>> {
>> int ret;
>> struct ibv_wc wc;
>> uint64_t wr_id;
>> - ret = ibv_poll_cq(rdma->cq, 1, &wc);
>> + if (wrid_requested == RDMA_WRID_RDMA_WRITE ||
>> + wrid_requested == RDMA_WRID_SEND_CONTROL) {
>> + ret = ibv_poll_cq(rdma->send_cq, 1, &wc);
>> + } else if (wrid_requested >= RDMA_WRID_RECV_CONTROL) {
>> + ret = ibv_poll_cq(rdma->recv_cq, 1, &wc);
>> + }
>> if (!ret) {
>> *wr_id_out = RDMA_WRID_NONE;
>> @@ -1460,12 +1472,9 @@ static int 
>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>> void *cq_ctx;
>> uint64_t wr_id = RDMA_WRID_NONE, wr_id_in;
>> - if (ibv_req_notify_cq(rdma->cq, 0)) {
>> - return -1;
>> - }
>> /* poll cq first */
>> while (wr_id != wrid_requested) {
>> - ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
>> + ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len, wrid_requested);
>> if (ret < 0) {
>> return ret;
>> }
>> @@ -1487,6 +1496,17 @@ static int 
>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>> }
>> while (1) {
>> + if (wrid_requested == RDMA_WRID_RDMA_WRITE ||
>> + wrid_requested == RDMA_WRID_SEND_CONTROL) {
>> + if (ibv_req_notify_cq(rdma->send_cq, 0)) {
>> + return -1;
>> + }
>> + } else if (wrid_requested >= RDMA_WRID_RECV_CONTROL) {
>> + if (ibv_req_notify_cq(rdma->recv_cq, 0)) {
>> + return -1;
>> + }
>> + }
>> +
>> /*
>> * Coroutine doesn't start until process_incoming_migration()
>> * so don't yield unless we know we're running inside of a coroutine.
>> @@ -1502,12 +1522,8 @@ static int 
>> qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
>> num_cq_events++;
>> - if (ibv_req_notify_cq(cq, 0)) {
>> - goto err_block_for_wrid;
>> - }
>> -
>> while (wr_id != wrid_requested) {
>> - ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
>> + ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len, wrid_requested);
>> if (ret < 0) {
>> goto err_block_for_wrid;
>> }
>> @@ -2236,9 +2252,13 @@ static void qemu_rdma_cleanup(RDMAContext *rdma)
>> ibv_destroy_qp(rdma->qp);
>> rdma->qp = NULL;
>> }
>> - if (rdma->cq) {
>> - ibv_destroy_cq(rdma->cq);
>> - rdma->cq = NULL;
>> + if (rdma->send_cq) {
>> + ibv_destroy_cq(rdma->send_cq);
>> + rdma->send_cq = NULL;
>> + }
>> + if (rdma->recv_cq) {
>> + ibv_destroy_cq(rdma->recv_cq);
>> + rdma->recv_cq = NULL;
>> }
>> if (rdma->comp_channel) {
>> ibv_destroy_comp_channel(rdma->comp_channel);
>> @@ -2770,7 +2790,7 @@ static size_t qemu_rdma_save_page(QEMUFile *f, 
>> void *opaque,
>> */
>> while (1) {
>> uint64_t wr_id, wr_id_in;
>> - int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL);
>> + int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL, RDMA_WRID_RDMA_WRITE);
>> if (ret < 0) {
>> fprintf(stderr, "rdma migration: polling error! %d\n", ret);
>> goto err;
>
> This seems like a harmless enough patch.
>
> Please create a properly-formatted V2 patch and resend to the mailing 
> list.
>
> - Michael
>
Acknowledged.

-- 
Frank