> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Friday, March 31, 2023 11:43 PM
> To: dev@dpdk.org; david.march...@redhat.com; Xia, Chenbo
> <chenbo....@intel.com>; m...@redhat.com; f...@redhat.com;
> jasow...@redhat.com; Liang, Cunming <cunming.li...@intel.com>; Xie, Yongji
> <xieyon...@bytedance.com>; echau...@redhat.com; epere...@redhat.com;
> amore...@redhat.com
> Cc: Maxime Coquelin <maxime.coque...@redhat.com>; sta...@dpdk.org
> Subject: [RFC 06/27] vhost: don't dump unneeded pages with IOTLB
>
> On IOTLB entry removal, previous fixes took care of not
> marking pages shared with other IOTLB entries as DONTDUMP.
>
> However, if an IOTLB entry is spanned on multiple pages,
> the other pages were kept as DODUMP while they might not
> have been shared with other entries, increasing needlessly
> the coredump size.
>
> This patch addresses this issue by excluding only the
> shared pages from madvise's DONTDUMP.
>
> Fixes: dea092d0addb ("vhost: fix madvise arguments alignment")
> Cc: sta...@dpdk.org
>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> lib/vhost/iotlb.c | 21 ++++++++++++++-------
> 1 file changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/lib/vhost/iotlb.c b/lib/vhost/iotlb.c
> index d919f74704..f598c0a8c4 100644
> --- a/lib/vhost/iotlb.c
> +++ b/lib/vhost/iotlb.c
> @@ -54,16 +54,23 @@ static void
> vhost_user_iotlb_clear_dump(struct virtio_net *dev, struct
> vhost_iotlb_entry *node,
> struct vhost_iotlb_entry *prev, struct vhost_iotlb_entry *next)
> {
> - uint64_t align;
> + uint64_t align, start, end;
> +
> + start = node->uaddr;
> + end = node->uaddr + node->size;
>
> align = hua_to_alignment(dev->mem, (void *)(uintptr_t)node->uaddr);
>
> - /* Don't disable coredump if the previous node is in the same page
> */
> - if (!vhost_user_iotlb_share_page(prev, node, align)) {
> - /* Don't disable coredump if the next node is in the same page
> */
> - if (!vhost_user_iotlb_share_page(node, next, align))
> - mem_set_dump((void *)(uintptr_t)node->uaddr, node->size,
> false, align);
> - }
> + /* Skip first page if shared with previous entry. */
> + if (vhost_user_iotlb_share_page(prev, node, align))
> + start = RTE_ALIGN_CEIL(start, align);
> +
> + /* Skip last page if shared with next entry. */
> + if (vhost_user_iotlb_share_page(node, next, align))
> + end = RTE_ALIGN_FLOOR(end, align);
> +
> + if (end > start)
> + mem_set_dump((void *)(uintptr_t)start, end - start, false,
> align);
> }
>
> static struct vhost_iotlb_entry *
> --
> 2.39.2
Reviewed-by: Chenbo Xia <chenbo....@intel.com>
