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Date: Tue, 11 Feb 2025 18:46:19 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Mina Almasry <almasrymina@google.com>
Cc: Jason Xing <kerneljasonxing@gmail.com>, davem@davemloft.net,
 edumazet@google.com, pabeni@redhat.com, hawk@kernel.org,
 ilias.apalodimas@linaro.org, horms@kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH net-next v1] page_pool: avoid infinite loop to schedule
 delayed worker
Message-ID: <20250211184619.7d69c99d@kernel.org>
In-Reply-To: <CAHS8izMznEB7TWkc4zxBhFF+8JVmstFoRfqfsRLOOMbcuUoRRA@mail.gmail.com>
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On Tue, 11 Feb 2025 18:37:22 -0800 Mina Almasry wrote:
> Isn't it the condition in page_pool_release_retry() that you want. to
> modify? That is the one that handles whether the worker keeps spinning
> no?

+1

A code comment may be useful BTW.

> I also wonder also whether if the check in page_pool_release() itself
> needs to be:
> 
> if (inflight < 0)
>   __page_pool_destroy();
> 
> otherwise the pool will never be destroyed no?

It's probably safer to leak the memory than risk a crash if 
we undercounted and some page will try to return itself later?