[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v4 12/29] postcopy+vhost-user: Split set_mem_tab
From: |
Dr. David Alan Gilbert |
Subject: |
Re: [Qemu-devel] [PATCH v4 12/29] postcopy+vhost-user: Split set_mem_table for postcopy |
Date: |
Mon, 12 Mar 2018 14:00:00 +0000 |
User-agent: |
Mutt/1.9.2 (2017-12-15) |
* Marc-André Lureau (address@hidden) wrote:
> Hi
>
> On Mon, Mar 12, 2018 at 10:57 AM, Peter Xu <address@hidden> wrote:
> > On Thu, Mar 08, 2018 at 07:57:54PM +0000, Dr. David Alan Gilbert (git)
> > wrote:
> >> From: "Dr. David Alan Gilbert" <address@hidden>
> >>
> >> Split the set_mem_table routines in both qemu and libvhost-user
> >> because the postcopy versions are going to be quite different
> >> once changes in the later patches are added.
>
> You could add that this does not introduce functional change.
Done.
Dave
> >>
> >> Signed-off-by: Dr. David Alan Gilbert <address@hidden>
> >> ---
> >> contrib/libvhost-user/libvhost-user.c | 53 ++++++++++++++++++++++++
> >> hw/virtio/vhost-user.c | 77
> >> ++++++++++++++++++++++++++++++++++-
> >> 2 files changed, 128 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/contrib/libvhost-user/libvhost-user.c
> >> b/contrib/libvhost-user/libvhost-user.c
> >> index beec7695a8..4922b2c722 100644
> >> --- a/contrib/libvhost-user/libvhost-user.c
> >> +++ b/contrib/libvhost-user/libvhost-user.c
> >> @@ -448,6 +448,55 @@ vu_reset_device_exec(VuDev *dev, VhostUserMsg *vmsg)
> >> return false;
> >> }
> >>
> >> +static bool
> >> +vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg)
> >> +{
> >> + int i;
> >> + VhostUserMemory *memory = &vmsg->payload.memory;
> >> + dev->nregions = memory->nregions;
> >> + /* TODO: Postcopy specific code */
> >> + DPRINT("Nregions: %d\n", memory->nregions);
> >> + for (i = 0; i < dev->nregions; i++) {
> >> + void *mmap_addr;
> >> + VhostUserMemoryRegion *msg_region = &memory->regions[i];
> >> + VuDevRegion *dev_region = &dev->regions[i];
> >> +
> >> + DPRINT("Region %d\n", i);
> >> + DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n",
> >> + msg_region->guest_phys_addr);
> >> + DPRINT(" memory_size: 0x%016"PRIx64"\n",
> >> + msg_region->memory_size);
> >> + DPRINT(" userspace_addr 0x%016"PRIx64"\n",
> >> + msg_region->userspace_addr);
> >> + DPRINT(" mmap_offset 0x%016"PRIx64"\n",
> >> + msg_region->mmap_offset);
> >> +
> >> + dev_region->gpa = msg_region->guest_phys_addr;
> >> + dev_region->size = msg_region->memory_size;
> >> + dev_region->qva = msg_region->userspace_addr;
> >> + dev_region->mmap_offset = msg_region->mmap_offset;
> >> +
> >> + /* We don't use offset argument of mmap() since the
> >> + * mapped address has to be page aligned, and we use huge
> >> + * pages. */
> >> + mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
> >> + PROT_READ | PROT_WRITE, MAP_SHARED,
> >> + vmsg->fds[i], 0);
> >> +
> >> + if (mmap_addr == MAP_FAILED) {
> >> + vu_panic(dev, "region mmap error: %s", strerror(errno));
> >> + } else {
> >> + dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
> >> + DPRINT(" mmap_addr: 0x%016"PRIx64"\n",
> >> + dev_region->mmap_addr);
> >> + }
> >> +
> >> + close(vmsg->fds[i]);
> >> + }
> >> +
> >> + return false;
> >> +}
> >> +
> >> static bool
> >> vu_set_mem_table_exec(VuDev *dev, VhostUserMsg *vmsg)
> >> {
> >> @@ -464,6 +513,10 @@ vu_set_mem_table_exec(VuDev *dev, VhostUserMsg *vmsg)
> >> }
> >> dev->nregions = memory->nregions;
> >>
> >> + if (dev->postcopy_listening) {
> >> + return vu_set_mem_table_exec_postcopy(dev, vmsg);
> >> + }
> >> +
> >> DPRINT("Nregions: %d\n", memory->nregions);
> >> for (i = 0; i < dev->nregions; i++) {
> >> void *mmap_addr;
> >> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> >> index ee200f703e..311addc33b 100644
> >> --- a/hw/virtio/vhost-user.c
> >> +++ b/hw/virtio/vhost-user.c
> >> @@ -340,15 +340,86 @@ static int vhost_user_set_log_base(struct vhost_dev
> >> *dev, uint64_t base,
> >> return 0;
> >> }
> >>
> >> +static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev,
> >> + struct vhost_memory *mem)
> >> +{
> >> + int fds[VHOST_MEMORY_MAX_NREGIONS];
> >> + int i, fd;
> >> + size_t fd_num = 0;
> >> + bool reply_supported = virtio_has_feature(dev->protocol_features,
> >> +
> >> VHOST_USER_PROTOCOL_F_REPLY_ACK);
> >> + /* TODO: Add actual postcopy differences */
> >> + VhostUserMsg msg = {
> >> + .hdr.request = VHOST_USER_SET_MEM_TABLE,
> >> + .hdr.flags = VHOST_USER_VERSION,
> >> + };
> >> +
> >> + if (reply_supported) {
> >> + msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
> >> + }
> >> +
> >> + for (i = 0; i < dev->mem->nregions; ++i) {
> >> + struct vhost_memory_region *reg = dev->mem->regions + i;
> >> + ram_addr_t offset;
> >> + MemoryRegion *mr;
> >> +
> >> + assert((uintptr_t)reg->userspace_addr == reg->userspace_addr);
> >> + mr = memory_region_from_host((void
> >> *)(uintptr_t)reg->userspace_addr,
> >> + &offset);
> >> + fd = memory_region_get_fd(mr);
> >> + if (fd > 0) {
> >> + msg.payload.memory.regions[fd_num].userspace_addr =
> >> + reg->userspace_addr;
> >> + msg.payload.memory.regions[fd_num].memory_size =
> >> reg->memory_size;
> >> + msg.payload.memory.regions[fd_num].guest_phys_addr =
> >> + reg->guest_phys_addr;
> >> + msg.payload.memory.regions[fd_num].mmap_offset = offset;
> >> + assert(fd_num < VHOST_MEMORY_MAX_NREGIONS);
> >> + fds[fd_num++] = fd;
> >> + }
> >> + }
> >> +
> >> + msg.payload.memory.nregions = fd_num;
> >> +
> >> + if (!fd_num) {
> >> + error_report("Failed initializing vhost-user memory map, "
> >> + "consider using -object memory-backend-file
> >> share=on");
> >> + return -1;
> >> + }
> >> +
> >> + msg.hdr.size = sizeof(msg.payload.memory.nregions);
> >> + msg.hdr.size += sizeof(msg.payload.memory.padding);
> >> + msg.hdr.size += fd_num * sizeof(VhostUserMemoryRegion);
> >> +
> >> + if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
> >> + return -1;
> >> + }
> >> +
> >> + if (reply_supported) {
> >> + return process_message_reply(dev, &msg);
> >> + }
> >> +
> >> + return 0;
> >> +}
> >> +
> >> static int vhost_user_set_mem_table(struct vhost_dev *dev,
> >> struct vhost_memory *mem)
> >> {
> >> + struct vhost_user *u = dev->opaque;
> >> int fds[VHOST_MEMORY_MAX_NREGIONS];
> >> int i, fd;
> >> size_t fd_num = 0;
> >> + bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler;
> >> bool reply_supported = virtio_has_feature(dev->protocol_features,
> >>
> >> VHOST_USER_PROTOCOL_F_REPLY_ACK);
> >>
> >> + if (do_postcopy) {
> >> + /* Postcopy has enough differences that it's best done in it's own
> >> + * version
> >> + */
> >> + return vhost_user_set_mem_table_postcopy(dev, mem);
> >> + }
> >> +
> >> VhostUserMsg msg = {
> >> .hdr.request = VHOST_USER_SET_MEM_TABLE,
> >> .hdr.flags = VHOST_USER_VERSION,
> >> @@ -372,9 +443,11 @@ static int vhost_user_set_mem_table(struct vhost_dev
> >> *dev,
> >> error_report("Failed preparing vhost-user memory table
> >> msg");
> >> return -1;
> >> }
> >> - msg.payload.memory.regions[fd_num].userspace_addr =
> >> reg->userspace_addr;
> >> + msg.payload.memory.regions[fd_num].userspace_addr =
> >> + reg->userspace_addr;
> >> msg.payload.memory.regions[fd_num].memory_size =
> >> reg->memory_size;
> >> - msg.payload.memory.regions[fd_num].guest_phys_addr =
> >> reg->guest_phys_addr;
> >> + msg.payload.memory.regions[fd_num].guest_phys_addr =
> >> + reg->guest_phys_addr;
> >
> > I would still prefer to generalize things out as shared functions,
> > since otherwise we are adding somehow duplicate codes, which is IMHO
> > harder to maintain. And even if to do the duplication, I would keep
> > the original code untouched (so these newlines will still not be
> > needed).
> >
> > But considering that the series has been there for a long time, I'll
> > try to be less harsh... And yes, I know it's a burden to maintain
> > private trees and keep rebasing.
> >
> > Feel free to remove the newlines (so at least commit log of those
> > lines won't be modified), and either way I'll offer mine:
> >
> > Reviewed-by: Peter Xu <address@hidden>
>
> I have the same feeling as Peter, but otherwise no objection - we can
> try to factorize again later if possible:
>
> Reviewed-by: Marc-André Lureau <address@hidden>
Thanks
Dave
>
> >
> > Thanks,
> >
> >> msg.payload.memory.regions[fd_num].mmap_offset = offset;
> >> fds[fd_num++] = fd;
> >> }
> >> --
> >> 2.14.3
> >>
> >
> > --
> > Peter Xu
> >
>
>
>
> --
> Marc-André Lureau
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK