Message ID | 1594867315-8626-6-git-send-email-teawater@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | virtio_balloon: Add VIRTIO_BALLOON_F_CONT_PAGES to report continuous pages | expand |
On Thu, Jul 16, 2020 at 10:41:55AM +0800, Hui Zhu wrote: > This commit adds a vq dcvq to deflate continuous pages. > When VIRTIO_BALLOON_F_CONT_PAGES is set, try to get continuous pages > from icvq and use madvise MADV_WILLNEED with the pages. > > Signed-off-by: Hui Zhu <teawaterz@linux.alibaba.com> This is arguably something to benchmark. Does guest benefit from MADV_WILLNEED or loose performance? > --- > hw/virtio/virtio-balloon.c | 14 +++++++++----- > include/hw/virtio/virtio-balloon.h | 2 +- > 2 files changed, 10 insertions(+), 6 deletions(-) > > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index d36a5c8..165adf7 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -138,7 +138,8 @@ static void balloon_inflate_page(VirtIOBalloon *balloon, > } > > static void balloon_deflate_page(VirtIOBalloon *balloon, > - MemoryRegion *mr, hwaddr mr_offset) > + MemoryRegion *mr, hwaddr mr_offset, > + size_t size) > { > void *addr = memory_region_get_ram_ptr(mr) + mr_offset; > ram_addr_t rb_offset; > @@ -153,10 +154,11 @@ static void balloon_deflate_page(VirtIOBalloon *balloon, > rb_page_size = qemu_ram_pagesize(rb); > > host_addr = (void *)((uintptr_t)addr & ~(rb_page_size - 1)); > + size &= ~(rb_page_size - 1); > > /* When a page is deflated, we hint the whole host page it lives > * on, since we can't do anything smaller */ > - ret = qemu_madvise(host_addr, rb_page_size, QEMU_MADV_WILLNEED); > + ret = qemu_madvise(host_addr, size, QEMU_MADV_WILLNEED); > if (ret != 0) { > warn_report("Couldn't MADV_WILLNEED on balloon deflate: %s", > strerror(errno)); > @@ -354,7 +356,7 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) > pa = (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT; > offset += 4; > > - if (vq == s->icvq) { > + if (vq == s->icvq || vq == s->dcvq) { > uint32_t psize_ptr; > if (iov_to_buf(elem->out_sg, elem->out_num, offset, &psize_ptr, 4) != 4) { > break; > @@ -383,8 +385,9 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) > balloon_inflate_page(s, section.mr, > section.offset_within_region, > psize, &pbp); > - } else if (vq == s->dvq) { > - balloon_deflate_page(s, section.mr, section.offset_within_region); > + } else if (vq == s->dvq || vq == s->dcvq) { > + balloon_deflate_page(s, section.mr, section.offset_within_region, > + psize); > } else { > g_assert_not_reached(); > } > @@ -838,6 +841,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) > > if (virtio_has_feature(s->host_features, VIRTIO_BALLOON_F_CONT_PAGES)) { > s->icvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); > + s->dcvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); > } > > reset_stats(s); > diff --git a/include/hw/virtio/virtio-balloon.h b/include/hw/virtio/virtio-balloon.h > index 6a2514d..848a7fb 100644 > --- a/include/hw/virtio/virtio-balloon.h > +++ b/include/hw/virtio/virtio-balloon.h > @@ -42,7 +42,7 @@ enum virtio_balloon_free_page_report_status { > > typedef struct VirtIOBalloon { > VirtIODevice parent_obj; > - VirtQueue *ivq, *dvq, *svq, *free_page_vq, *icvq; > + VirtQueue *ivq, *dvq, *svq, *free_page_vq, *icvq, *dcvq; > uint32_t free_page_report_status; > uint32_t num_pages; > uint32_t actual; > -- > 2.7.4
> 2020年7月16日 14:39,Michael S. Tsirkin <mst@redhat.com> 写道: > > On Thu, Jul 16, 2020 at 10:41:55AM +0800, Hui Zhu wrote: >> This commit adds a vq dcvq to deflate continuous pages. >> When VIRTIO_BALLOON_F_CONT_PAGES is set, try to get continuous pages >> from icvq and use madvise MADV_WILLNEED with the pages. >> >> Signed-off-by: Hui Zhu <teawaterz@linux.alibaba.com> > > This is arguably something to benchmark. Does guest benefit > from MADV_WILLNEED or loose performance? MADV_WILLNEED will call madvise_willneed in the host kernel. madvise_willneed will schedule all required I/O operations (swap in or vfs_fadvise POSIX_FADV_WILLNEED) of the address. But the pages of the balloon are released by MADV_DONTNEED. So I think MADV_WILLNEED will not affect the performance of the guest in the most of situations. Best, Hui > >> --- >> hw/virtio/virtio-balloon.c | 14 +++++++++----- >> include/hw/virtio/virtio-balloon.h | 2 +- >> 2 files changed, 10 insertions(+), 6 deletions(-) >> >> diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c >> index d36a5c8..165adf7 100644 >> --- a/hw/virtio/virtio-balloon.c >> +++ b/hw/virtio/virtio-balloon.c >> @@ -138,7 +138,8 @@ static void balloon_inflate_page(VirtIOBalloon *balloon, >> } >> >> static void balloon_deflate_page(VirtIOBalloon *balloon, >> - MemoryRegion *mr, hwaddr mr_offset) >> + MemoryRegion *mr, hwaddr mr_offset, >> + size_t size) >> { >> void *addr = memory_region_get_ram_ptr(mr) + mr_offset; >> ram_addr_t rb_offset; >> @@ -153,10 +154,11 @@ static void balloon_deflate_page(VirtIOBalloon *balloon, >> rb_page_size = qemu_ram_pagesize(rb); >> >> host_addr = (void *)((uintptr_t)addr & ~(rb_page_size - 1)); >> + size &= ~(rb_page_size - 1); >> >> /* When a page is deflated, we hint the whole host page it lives >> * on, since we can't do anything smaller */ >> - ret = qemu_madvise(host_addr, rb_page_size, QEMU_MADV_WILLNEED); >> + ret = qemu_madvise(host_addr, size, QEMU_MADV_WILLNEED); >> if (ret != 0) { >> warn_report("Couldn't MADV_WILLNEED on balloon deflate: %s", >> strerror(errno)); >> @@ -354,7 +356,7 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) >> pa = (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT; >> offset += 4; >> >> - if (vq == s->icvq) { >> + if (vq == s->icvq || vq == s->dcvq) { >> uint32_t psize_ptr; >> if (iov_to_buf(elem->out_sg, elem->out_num, offset, &psize_ptr, 4) != 4) { >> break; >> @@ -383,8 +385,9 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) >> balloon_inflate_page(s, section.mr, >> section.offset_within_region, >> psize, &pbp); >> - } else if (vq == s->dvq) { >> - balloon_deflate_page(s, section.mr, section.offset_within_region); >> + } else if (vq == s->dvq || vq == s->dcvq) { >> + balloon_deflate_page(s, section.mr, section.offset_within_region, >> + psize); >> } else { >> g_assert_not_reached(); >> } >> @@ -838,6 +841,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) >> >> if (virtio_has_feature(s->host_features, VIRTIO_BALLOON_F_CONT_PAGES)) { >> s->icvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); >> + s->dcvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); >> } >> >> reset_stats(s); >> diff --git a/include/hw/virtio/virtio-balloon.h b/include/hw/virtio/virtio-balloon.h >> index 6a2514d..848a7fb 100644 >> --- a/include/hw/virtio/virtio-balloon.h >> +++ b/include/hw/virtio/virtio-balloon.h >> @@ -42,7 +42,7 @@ enum virtio_balloon_free_page_report_status { >> >> typedef struct VirtIOBalloon { >> VirtIODevice parent_obj; >> - VirtQueue *ivq, *dvq, *svq, *free_page_vq, *icvq; >> + VirtQueue *ivq, *dvq, *svq, *free_page_vq, *icvq, *dcvq; >> uint32_t free_page_report_status; >> uint32_t num_pages; >> uint32_t actual; >> -- >> 2.7.4 > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org > For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index d36a5c8..165adf7 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -138,7 +138,8 @@ static void balloon_inflate_page(VirtIOBalloon *balloon, } static void balloon_deflate_page(VirtIOBalloon *balloon, - MemoryRegion *mr, hwaddr mr_offset) + MemoryRegion *mr, hwaddr mr_offset, + size_t size) { void *addr = memory_region_get_ram_ptr(mr) + mr_offset; ram_addr_t rb_offset; @@ -153,10 +154,11 @@ static void balloon_deflate_page(VirtIOBalloon *balloon, rb_page_size = qemu_ram_pagesize(rb); host_addr = (void *)((uintptr_t)addr & ~(rb_page_size - 1)); + size &= ~(rb_page_size - 1); /* When a page is deflated, we hint the whole host page it lives * on, since we can't do anything smaller */ - ret = qemu_madvise(host_addr, rb_page_size, QEMU_MADV_WILLNEED); + ret = qemu_madvise(host_addr, size, QEMU_MADV_WILLNEED); if (ret != 0) { warn_report("Couldn't MADV_WILLNEED on balloon deflate: %s", strerror(errno)); @@ -354,7 +356,7 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) pa = (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT; offset += 4; - if (vq == s->icvq) { + if (vq == s->icvq || vq == s->dcvq) { uint32_t psize_ptr; if (iov_to_buf(elem->out_sg, elem->out_num, offset, &psize_ptr, 4) != 4) { break; @@ -383,8 +385,9 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) balloon_inflate_page(s, section.mr, section.offset_within_region, psize, &pbp); - } else if (vq == s->dvq) { - balloon_deflate_page(s, section.mr, section.offset_within_region); + } else if (vq == s->dvq || vq == s->dcvq) { + balloon_deflate_page(s, section.mr, section.offset_within_region, + psize); } else { g_assert_not_reached(); } @@ -838,6 +841,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) if (virtio_has_feature(s->host_features, VIRTIO_BALLOON_F_CONT_PAGES)) { s->icvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); + s->dcvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); } reset_stats(s); diff --git a/include/hw/virtio/virtio-balloon.h b/include/hw/virtio/virtio-balloon.h index 6a2514d..848a7fb 100644 --- a/include/hw/virtio/virtio-balloon.h +++ b/include/hw/virtio/virtio-balloon.h @@ -42,7 +42,7 @@ enum virtio_balloon_free_page_report_status { typedef struct VirtIOBalloon { VirtIODevice parent_obj; - VirtQueue *ivq, *dvq, *svq, *free_page_vq, *icvq; + VirtQueue *ivq, *dvq, *svq, *free_page_vq, *icvq, *dcvq; uint32_t free_page_report_status; uint32_t num_pages; uint32_t actual;
This commit adds a vq dcvq to deflate continuous pages. When VIRTIO_BALLOON_F_CONT_PAGES is set, try to get continuous pages from icvq and use madvise MADV_WILLNEED with the pages. Signed-off-by: Hui Zhu <teawaterz@linux.alibaba.com> --- hw/virtio/virtio-balloon.c | 14 +++++++++----- include/hw/virtio/virtio-balloon.h | 2 +- 2 files changed, 10 insertions(+), 6 deletions(-)