Re: [PATCH net-next] net: add in_softirq() debug checking in napi_consume_skb()

[Peter Zijlstra]

On Wed, Nov 18, 2020 at 07:43:48AM -0800, Jakub Kicinski wrote:

> TBH the last sentence I wrote isn't clear even to me at this point ;D
> 
> Maybe using just the macros from preempt.h - like this?
> 
> #define lockdep_assert_in_softirq()                                    \
> do {                                                                   \
>        WARN_ON_ONCE(__lockdep_enabled                  &&              \
>                     (!in_softirq() || in_irq() || in_nmi())	\
> } while (0)
> 
> We know what we're doing so in_softirq() should be fine (famous last
> words).

So that's not actually using any lockdep state. But if that's what you
need, I don't have any real complaints.