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Mon, 26 Oct 2026 19:32:55 -0700 (PDT) Received: from [192.168.1.106] ([198.8.77.135]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-198a21bc6cbsm28324365c88.16.2026.10.26.19.32.55 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 26 Oct 2026 19:32:55 -0700 (PDT) Message-ID: <51d9c80e-1bfc-43e5-a195-46b4b7612de1@kernel.dk> Date: Mon, 26 Oct 2026 20:32:54 -0600 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] io_uring/napi: drop the single NAPI busy poll special case To: Cinq Prairie Cc: Stefan Roesch , Jakub Kicinski , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org References: <20261026231718.5092-1-notprairie@gmail.com> Content-Language: en-US From: Jens Axboe In-Reply-To: <20261026231718.5092-1-notprairie@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/26/26 5:17 PM, Cinq Prairie wrote: > I'm thinking that with the re-entry in place io_uring can cond_resched() > when the napi loop bailed on a need_resched() then resume, between laps > it holds nothing from the list and is in sleepable context. That would > mirror the socket path. Though it also impacts the multi-NAPI path, > which never yielded so far, so I'd like your preference: include it in > v2, or keep v2 to the single-NAPI fix and send the yield as a follow-up? Let's keep v2 the single-NAPI fix, and then you can do a follow-up on top of that. > I'll also add numbers for the single-NAPI fast path when it is not cut > short, before/after, so the cost is visible. Sounds good, thanks! -- Jens Axboe