If the VIRTIO_RING_F_INDIRECT_DESC negotiation succeeds, and the number of sgs used for sending packets is greater than 1. We must constantly call __kmalloc/kfree to allocate/release desc. In the case of extremely fast package delivery, the overhead cannot be ignored: 27.46% [kernel] [k] virtqueue_add 16.66% [kernel] [k] detach_buf_split 16.51% [kernel] [k] virtnet_xsk_xmit 14.04% [kernel] [k] virtqueue_add_outbuf 5.18% [kernel] [k] __kmalloc 4.08% [kernel] [k] kfree 2.80% [kernel] [k] virtqueue_get_buf_ctx 2.22% [kernel] [k] xsk_tx_peek_desc 2.08% [kernel] [k] memset_erms 0.83% [kernel] [k] virtqueue_kick_prepare 0.76% [kernel] [k] virtnet_xsk_run 0.62% [kernel] [k] __free_old_xmit_ptr 0.60% [kernel] [k] vring_map_one_sg 0.53% [kernel] [k] native_apic_mem_write 0.46% [kernel] [k] sg_next 0.43% [kernel] [k] sg_init_table 0.41% [kernel] [k] kmalloc_slab This patch adds a cache function to virtio to cache these allocated indirect desc instead of constantly allocating and releasing desc. v3: pre-allocate per buffer indirect descriptors array v2: use struct list_head to cache the desc *** BLURB HERE *** Xuan Zhuo (3): virtio: cache indirect desc for split virtio: cache indirect desc for packed virtio-net: enable virtio desc cache drivers/net/virtio_net.c | 11 +++ drivers/virtio/virtio.c | 6 ++ drivers/virtio/virtio_ring.c | 131 ++++++++++++++++++++++++++++++----- include/linux/virtio.h | 14 ++++ 4 files changed, 145 insertions(+), 17 deletions(-) -- 2.31.0 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
