On Tue, 20 May 2025 15:05:34 +0800 Jinjian Song wrote:
> >Synchronization is about ensuring that the condition validating
> >by the if() remains true for as long as necessary.
> >You need to wrap the read with READ_ONCE() and write with WRITE_ONCE().
> >The rest if fine because netdev unregister sync against NAPIs in flight.
> >
>
> Hi Jakub,
> I think I got your point.
> I can use the atomic_t usage in struct t7xx_ccmni to synchronization.
>
> static void t7xx_ccmni_wwan_dellink(...) {
>
> [...]
>
> if (WARN_ON(ctlb->ccmni_inst[if_id] != ccmni))
> return;
>
> unregister_netdevice(dev);
>
> //Add here use this variable(ccmnii->usage) to synchronization
>
> if (atomic_read(&ccmni->usage) == 0)
> ccmni == NULL;
>
> }
>
> How about this modify?
Just use READ_ONCE() / WRITE_ONCE() on the pointer as I suggested.
