Hi Yi, On Wed, Sep 20, 2017 at 04:32:03PM +0800, Yi Yang wrote: > Usually vhost_user message VHOST_USER_SET_MEM_TABLE > is only sent out during initialization and only sent > once, but it isn't so for memory hotplug and hotunplug > , for that case, vhost_user message VHOST_USER_SET_MEM_TABLE > will be resent with the old memory regions (not hotunplugged) > and the new memory regions (hotplugged), so current > vhost_user_set_mem_table implementation is wrong for > memory hotplug and hotunplug case, it will free current > memory regions and unmap hugepages no matter if they > are be using or not and if they are memory regions which > have been initialized and mapped in the previous vhost_user > message VHOST_USER_SET_MEM_TABLE or not. > > This commit fixed this issue very well, it will keep them > intact for those old memory region it will unmap those > memroy regions if they have been hotunplugged, it will > initialize the new hotplugged memory regions and map > hugepages if they are hotplugged. > > vhost_user message VHOST_USER_SET_MEM_TABLE will include > all the current effective memory regions, the hotunplugged > memory regions won't be included in VHOST_USER_SET_MEM_TABLE, > the hotplugged memroy regions will be included in > VHOST_USER_SET_MEM_TABLE. > > This has been verified in OVS DPDK by memory hotplug and > hotunplug in qemu. > > Signed-off-by: Yi Yang <[email protected]> > --- > lib/librte_vhost/vhost_user.c | 72 > ++++++++++++++++++++++++++++++++++++++----- > 1 file changed, 65 insertions(+), 7 deletions(-) > > diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c > index ad2e8d3..1c475d1 100644 > --- a/lib/librte_vhost/vhost_user.c > +++ b/lib/librte_vhost/vhost_user.c [...] > @@ -532,7 +558,7 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct > VhostUserMsg *pmsg) > } > } > > - dev->mem = rte_zmalloc("vhost-mem-table", sizeof(struct > rte_vhost_memory) + > + dev->mem = rte_realloc(dev->mem, sizeof(struct rte_vhost_memory) +
The rte_realloc() will free the memory pointed by the dev->mem. But it's possible that some other threads are using it (e.g. by calling rte_vhost_gpa_to_vva()). It's an issue that needs to be fixed in this patch. Best regards, Tiwei Bie
