From patchwork Mon Sep 16 19:17:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Langlois X-Patchwork-Id: 13805760 Received: from cloud48395.mywhc.ca (cloud48395.mywhc.ca [173.209.37.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0102813210D for ; Mon, 16 Sep 2024 19:17:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=173.209.37.211 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726514281; cv=none; b=mI64iodlZ7Kcv71j4c8fCn6EJeyhG04Uqe/V3BQFm3+4mV4+Y3rI34nXIKjbyB1QRYwsqYppB1wY1893GasvZGzTQooiLsJ0BGZkmzBoye5OpwL2ZWCRlKyVp5LOay8HkRA29FJyNdD56gK8SVwi+WijXyfRVb0bYlDXw/O/lVE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726514281; c=relaxed/simple; bh=Pif03uLebz7j2yD6gu8mJsBQsgzSqXEf3VbKCMCfvqA=; h=From:Date:Message-ID:To:Subject; b=AgPZ1v9MmN5U/giTaoNi8nmgVSdtUep01x+Ba6yCdMIyasIeURqvJZALik1kDTH+jOcgIDiPcYCZSYoe48a8rt1Q+U/k75OvVb9Kp8E/MXUgIfNzru/UJbxmXY2hKB085y5J6f2mzczBmIrCzNOcfUoVU++0Ts1Hns+GoNvFGX4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=trillion01.com; spf=pass smtp.mailfrom=trillion01.com; arc=none smtp.client-ip=173.209.37.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=trillion01.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=trillion01.com Received: from [45.44.224.220] (port=53342 helo=localhost) by cloud48395.mywhc.ca with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96.2) (envelope-from ) id 1sqHES-0005xL-2a; Mon, 16 Sep 2024 15:17:56 -0400 From: Olivier Langlois Date: Mon, 16 Sep 2024 15:17:56 -0400 Message-ID: To: Jens Axboe ,Pavel Begunkov ,io-uring@vger.kernel.org Subject: [PATCH v3 RESEND] io_uring: do the sqpoll napi busy poll outside the submission block X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cloud48395.mywhc.ca X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - trillion01.com X-Get-Message-Sender-Via: cloud48395.mywhc.ca: authenticated_id: olivier@trillion01.com X-Authenticated-Sender: cloud48395.mywhc.ca: olivier@trillion01.com X-Source: X-Source-Args: X-Source-Dir: Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: there are many small reasons justifying this change. 1. busy poll must be performed even on rings that have no iopoll and no new sqe. It is quite possible that a ring configured for inbound traffic with multishot be several hours without receiving new request submissions 2. NAPI busy poll does not perform any credential validation 3. If the thread is awaken by task work, processing the task work is prioritary over NAPI busy loop. This is why a second loop has been created after the io_sq_tw() call instead of doing the busy loop in __io_sq_thread() outside its credential acquisition block. Signed-off-by: Olivier Langlois --- io_uring/sqpoll.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c index 3b50dc9586d1..f9964eb03803 100644 --- a/io_uring/sqpoll.c +++ b/io_uring/sqpoll.c @@ -195,9 +195,6 @@ static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries) ret = io_submit_sqes(ctx, to_submit); mutex_unlock(&ctx->uring_lock); - if (io_napi(ctx)) - ret += io_napi_sqpoll_busy_poll(ctx); - if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait)) wake_up(&ctx->sqo_sq_wait); if (creds) @@ -322,6 +319,10 @@ static int io_sq_thread(void *data) if (io_sq_tw(&retry_list, IORING_TW_CAP_ENTRIES_VALUE)) sqt_spin = true; + list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) + if (io_napi(ctx)) + io_napi_sqpoll_busy_poll(ctx); + if (sqt_spin || !time_after(jiffies, timeout)) { if (sqt_spin) { io_sq_update_worktime(sqd, &start);