Re: [PATCH] net: hinic: avoid kernel hung in hinic_get_stats64()

From: Eric Dumazet
Date: Thu Jun 30 2022 - 10:15:19 EST


On Thu, Jun 30, 2022 at 3:57 PM maqiao <mqaio@xxxxxxxxxxxxxxxxx> wrote:
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>
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> 在 2022/6/30 下午6:23, Eric Dumazet 写道:

> > Note: The following is racy, because multiple threads can call
> > hinic_get_stats64() at the same time.
> > It needs a loop, see include/linux/u64_stats_sync.h for detail.
> Thanks for reminding, and I noticed that nic_tx_stats/nic_rx_stats has
> been protected by u64_stats_sync in update_t/rx_stats(), it seems that
> it's unnecessary to use spinlock in update_nic_stats().

It is necessary to use the spinlock to protect writers among themselves.


>
> I will send v2 as soon as possible, thanks.