Re: [RFC, PATCH] kernel/rcu: add kfree_rcu

[Manfred Spraul <manfred@colorfullife.com>]

Paul E. McKenney wrote:
>
>> I think these two are different questions.
>> vfree() still can not be called from softirq context now.
>> And I proposed vfree_atomic() for RCU, but it can not be accepted.
>>     
>
> And one would indeed either need to have a vfree_atomic() or have some
> mechanism that sent the vfree() to a workqueue or some such.
>   
ipc/util.c uses a workqueue (ipc_schedule_free):
The semaphore array structure can be large (documented with SEMMSL=8000 
around 16 kB, but there is no  hard limit), thus vmalloc is used.

But as long as there are just one or two users, I doubt that a generic 
system is worth the effort.

--
    Manfred