On Fri, Jul 09, 2021 at 02:40:02PM +0800, Yunsheng Lin wrote:
On 2021/7/9 12:15, Matteo Croce wrote:
On Wed, Jul 7, 2021 at 6:50 PM Marcin Wojtas mw@semihalf.com wrote:
Hi,
??r., 7 lip 2021 o 01:20 Matteo Croce mcroce@linux.microsoft.com napisa??(a):
On Tue, Jul 6, 2021 at 5:51 PM Russell King (Oracle) linux@armlinux.org.uk wrote:
On Fri, Jul 02, 2021 at 03:39:47PM +0200, Matteo Croce wrote:
On Wed, 30 Jun 2021 17:17:54 +0800 Yunsheng Lin linyunsheng@huawei.com wrote:
> This patchset adds elevated refcnt support for page pool > and enable skb's page frag recycling based on page pool > in hns3 drvier. > > Yunsheng Lin (2): > page_pool: add page recycling support based on elevated refcnt > net: hns3: support skb's frag page recycling based on page pool > > drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 79 +++++++- > drivers/net/ethernet/hisilicon/hns3/hns3_enet.h | 3 + > drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c | 1 + > drivers/net/ethernet/marvell/mvneta.c | 6 +- > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 2 +- > include/linux/mm_types.h | 2 +- > include/linux/skbuff.h | 4 +- > include/net/page_pool.h | 30 ++- > net/core/page_pool.c | 215 > +++++++++++++++++---- 9 files changed, 285 insertions(+), 57 > deletions(-) >
Interesting! Unfortunately I'll not have access to my macchiatobin anytime soon, can someone test the impact, if any, on mvpp2?
I'll try to test. Please let me know what kind of testing you're looking for (I haven't been following these patches, sorry.)
A drop test or L2 routing will be enough. BTW I should have the macchiatobin back on friday.
I have a 10G packet generator connected to 10G ports of CN913x-DB - I will stress mvpp2 in l2 forwarding early next week (I'm mostly AFK this until Monday).
I managed to to a drop test on mvpp2. Maybe there is a slowdown but it's below the measurement uncertainty.
Perf top before:
Overhead Shared O Symbol 8.48% [kernel] [k] page_pool_put_page 2.57% [kernel] [k] page_pool_refill_alloc_cache 1.58% [kernel] [k] page_pool_alloc_pages 0.75% [kernel] [k] page_pool_return_skb_page
after:
Overhead Shared O Symbol 8.34% [kernel] [k] page_pool_put_page 4.52% [kernel] [k] page_pool_return_skb_page 4.42% [kernel] [k] page_pool_sub_bias 3.16% [kernel] [k] page_pool_alloc_pages 2.43% [kernel] [k] page_pool_refill_alloc_cache
Hi, Matteo Thanks for the testing. it seems you have adapted the mvpp2 driver to use the new frag API for page pool, There is one missing optimization for XDP case, the page is always returned to the pool->ring regardless of the context of page_pool_put_page() for elevated refcnt case.
Maybe adding back that optimization will close some gap of the above performance difference if the drop is happening in softirq context.
I think what Matteo did was a pure netstack test. We'll need testing on both XDP and normal network cases to be able to figure out the exact impact.
Thanks /Ilias
Regards,