Re: [PATCH 2/6] rhashtable: remove incorrect comment on r{hl, hash}table_walk_enter()

From: Herbert Xu
Date: Wed Apr 18 2018 - 10:29:08 EST


On Wed, Apr 18, 2018 at 04:47:01PM +1000, NeilBrown wrote:
> Neither rhashtable_walk_enter() or rhltable_walk_enter() sleep, so
> remove the comments which suggest that they do.
>
> Signed-off-by: NeilBrown <neilb@xxxxxxxx>
> ---
> include/linux/rhashtable.h | 3 ---
> lib/rhashtable.c | 3 ---
> 2 files changed, 6 deletions(-)
>
> diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h
> index 87d443a5b11d..b01d88e196c2 100644
> --- a/include/linux/rhashtable.h
> +++ b/include/linux/rhashtable.h
> @@ -1268,9 +1268,6 @@ static inline int rhashtable_walk_init(struct rhashtable *ht,
> * For a completely stable walk you should construct your own data
> * structure outside the hash table.
> *
> - * This function may sleep so you must not call it from interrupt
> - * context or with spin locks held.

It does a naked spin lock so even though we removed the memory
allocation you still mustn't call it from interrupt context.

Why do you need to do that anyway?

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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