On 6/18/21 6:34 AM, Xia, Chenbo wrote:
> Hi Maxime,
>
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coque...@redhat.com>
>> Sent: Thursday, June 17, 2021 11:38 PM
>> To: dev@dpdk.org; david.march...@redhat.com; Xia, Chenbo
>> <chenbo....@intel.com>
>> Cc: Maxime Coquelin <maxime.coque...@redhat.com>; sta...@dpdk.org
>> Subject: [PATCH v4 1/7] vhost: fix missing memory table NUMA realloc
>>
>> When the guest allocates virtqueues on a different NUMA node
>> than the one the Vhost metadata are allocated, both the Vhost
>> device struct and the virtqueues struct are reallocated.
>>
>> However, reallocating the Vhost memory table was missing, which
>> likely causes iat least one cross-NUMA accesses for every burst
>> of packets.
>
> 'at least' ?
yes.
>>
>> This patch reallocates this table on the same NUMA node as the
>> other metadata.
>>
>> Fixes: 552e8fd3d2b4 ("vhost: simplify memory regions handling")
>> Cc: sta...@dpdk.org
>>
>> Reported-by: David Marchand <david.march...@redhat.com>
>> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
>> ---
>> lib/vhost/vhost_user.c | 15 +++++++++++++++
>> 1 file changed, 15 insertions(+)
>>
>> diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
>> index 8f0eba6412..031e3bfa2f 100644
>> --- a/lib/vhost/vhost_user.c
>> +++ b/lib/vhost/vhost_user.c
>> @@ -557,6 +557,9 @@ numa_realloc(struct virtio_net *dev, int index)
>
> As we are realloc more things now, the comment above 'numa_realloc(XXX)'
> should also be changed like:
>
> Reallocate related data structure to make them on the same numa node as
> the memory of vring descriptor.
Agree, I'll put this:
"
Reallocate virtio_dev, vhost_virtqueue and related data structures to
make them on the same numa node as the memory of vring descriptor.
"
Thanks,
Maxime
> Thanks,
> Chenbo
>
>> goto out;
>> }
>> if (oldnode != newnode) {
>> + struct rte_vhost_memory *old_mem;
>> + ssize_t mem_size;
>> +
>> VHOST_LOG_CONFIG(INFO,
>> "reallocate dev from %d to %d node\n",
>> oldnode, newnode);
>> @@ -568,6 +571,18 @@ numa_realloc(struct virtio_net *dev, int index)
>>
>> memcpy(dev, old_dev, sizeof(*dev));
>> rte_free(old_dev);
>> +
>> + mem_size = sizeof(struct rte_vhost_memory) +
>> + sizeof(struct rte_vhost_mem_region) *
>> dev->mem->nregions;
>> + old_mem = dev->mem;
>> + dev->mem = rte_malloc_socket(NULL, mem_size, 0, newnode);
>> + if (!dev->mem) {
>> + dev->mem = old_mem;
>> + goto out;
>> + }
>> +
>> + memcpy(dev->mem, old_mem, mem_size);
>> + rte_free(old_mem);
>> }
>>
>> out:
>> --
>> 2.31.1
>
