[Linux-kernel-mentees][PATCH 0/2] reorder members of structures in virtio_net for optimization

From: Anant Thazhemadam
Date: Wed Sep 30 2020 - 01:17:42 EST


The structures virtnet_info and receive_queue have byte holes in
middle, and their members could do with some rearranging
(order-of-declaration wise) in order to overcome this.

Rearranging the members helps in:
* elimination the byte holes in the middle of the structures
* reduce the size of the structure (virtnet_info)
* have more members stored in one cache line (as opposed to
unnecessarily crossing the cacheline boundary and spanning
different cachelines)

The analysis was performed using pahole.

These patches may be applied in any order.

Anant Thazhemadam (2):
net: reorder members of virtnet_info for optimization
net: reorder members of receive_queue in virtio_net for optimization

drivers/net/virtio_net.c | 44 +++++++++++++++++++++-------------------
1 file changed, 23 insertions(+), 21 deletions(-)

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2.25.1