linux-kernel - Re: [RFC PATCH 68/86] treewide: mm: remove cond

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Date:   Wed, 8 Nov 2023 10:28:23 +0900
From:   Sergey Senozhatsky <senozhatsky@...omium.org>
To:     Ankur Arora <ankur.a.arora@...cle.com>
Cc:     linux-kernel@...r.kernel.org, tglx@...utronix.de,
        peterz@...radead.org, torvalds@...ux-foundation.org,
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Subject: Re: [RFC PATCH 68/86] treewide: mm: remove cond_resched()

On (23/11/07 15:08), Ankur Arora wrote:
[..]
> +++ b/mm/zsmalloc.c
> @@ -2029,7 +2029,6 @@ static unsigned long __zs_compact(struct zs_pool *pool,
>  			dst_zspage = NULL;
>  
>  			spin_unlock(&pool->lock);
> -			cond_resched();
>  			spin_lock(&pool->lock);
>  		}
>  	}

I'd personally prefer to have a comment explaining why we do that
spin_unlock/spin_lock sequence, which may look confusing to people.

Maybe would make sense to put a nice comment in all similar cases.
For instance:

  	rcu_read_unlock();
 -	cond_resched();
  	rcu_read_lock();