From patchwork Fri Nov 8 04:53:25 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joe Damato X-Patchwork-Id: 13867559 Received: from mail-pg1-f176.google.com (mail-pg1-f176.google.com [209.85.215.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C28D1D0DC7 for ; Fri, 8 Nov 2024 04:54:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.176 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731041679; cv=none; b=NGE3/1EwIOTX+yBLuc8A9421IfVRx+HrDmaU7XsyjB34KEbp06PiPclj3nM9YPN6dPnFdl/uZKU3VCQLd0WQX8jw095VN3ZJZb9RiNBr7bx/1cXWUqKPxVQuTyEDTIvNo3EU6tBAuEkdpMHloMcmmhpNOpj6Qh++vH/JUgZrqtM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731041679; c=relaxed/simple; bh=QMGh9V+fCN/j+D0uLjcnIHw3s7shm5dxlUbsYTeYPOY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=AM2gyKwmCuBffKwWHSRf7ngI/DSPlMgwgiLekwyvDplndzO8g1ZvAXf5euoKZ4v4dFPbV2o/Lwmf6GUv4uZjyI93yrMdImwUWkiYhDfT5Yo4derGDtahw8qOY63WcOApIbmu6h7+5xjYTGNy6NRZtF8zg9XVnb4zRYPyscHe148= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fastly.com; spf=pass smtp.mailfrom=fastly.com; dkim=pass (1024-bit key) header.d=fastly.com header.i=@fastly.com header.b=uOBRNlD3; arc=none smtp.client-ip=209.85.215.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fastly.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fastly.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=fastly.com header.i=@fastly.com header.b="uOBRNlD3" Received: by mail-pg1-f176.google.com with SMTP id 41be03b00d2f7-7ae3d7222d4so1256378a12.3 for ; Thu, 07 Nov 2024 20:54:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fastly.com; s=google; t=1731041677; x=1731646477; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=OCBpeWwUMYPpQhLDdrb3cMWwRM83RuSfCI6YlvdtYdM=; b=uOBRNlD3YjT6Nqi6l5UXnY1lblNHzzzEaOWmekCNRm7Ma6JcoaRW86L/vI3WG/DJAh EemzSXZ5EQ/oYjl3omt9tnEF1MR3Eo/4ms70fqiz2QYIVnoKtbEMc9rdu4TBQbjx9aHb 4hfQcBUyMSdHYqiMYpMIDNXLZsV3AaQYNtk0w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1731041677; x=1731646477; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=OCBpeWwUMYPpQhLDdrb3cMWwRM83RuSfCI6YlvdtYdM=; b=Kdrq9B86g94GFAhlZnASaanWHOwMk0DQrWjuyNFwHp5sVzF0oSrN7Jca8lVrXhht2Q MjiYFB+EfJBTkpSjU3X+r0eBteiRkERLDEvwah+E8N8046j7VSeo45CqZTm+57Pu/f4K BzSgyyJe40KJfOmCkxKrVuaV+KbJy4l5aHsixOoJR2Wc+3t8CaaNXWaDFH8wYor6Ztu2 jeEQ90CShf+VPD6clVX4X2w7AF4PTvm1bo+ZZDiS0h4hukptWqMAHYFafrNvEbWRuCKW d01C7eLlktrl13OfUy59FtIPBtf3W0m5AO/DASpfsu9r1cid+ChOU3nS9KxEN3HJwPeX 5/Gw== X-Forwarded-Encrypted: i=1; AJvYcCWUfDlX48F+PhW5JoRhhQdFu9L7rmu8foxr9VDSbwYp1sUFa9PpwNeAjIZHvUNJ4fPr/858dmdup4deYWUD@vger.kernel.org X-Gm-Message-State: AOJu0Yw1EwctZ7sqhIddRTBpJOG2T2FH5um6DKGbKCNl5P+Xw+IuBtPB QkIzM3bSARqt1lYoX3YK5HVQcj82xMdUGcHb0vy41uCxJ5e20xG500yV/jfi/zY= X-Google-Smtp-Source: AGHT+IGYzAbiAwauRFMMboqJSm+iCwXrgDOyCYgQe6F94CT0DzPWv4Q9veac5TXYOYehAWs9ZfUyEA== X-Received: by 2002:a05:6a21:3d88:b0:1d9:1971:bca9 with SMTP id adf61e73a8af0-1dc22a47884mr1473874637.24.1731041676722; Thu, 07 Nov 2024 20:54:36 -0800 (PST) Received: from localhost.localdomain ([2620:11a:c019:0:65e:3115:2f58:c5fd]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-724078a7c76sm2697476b3a.48.2024.11.07.20.54.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Nov 2024 20:54:36 -0800 (PST) From: Joe Damato To: netdev@vger.kernel.org Cc: corbet@lwn.net, hdanton@sina.com, bagasdotme@gmail.com, pabeni@redhat.com, namangulati@google.com, edumazet@google.com, amritha.nambiar@intel.com, sridhar.samudrala@intel.com, sdf@fomichev.me, peter@typeblog.net, m2shafiei@uwaterloo.ca, bjorn@rivosinc.com, hch@infradead.org, willy@infradead.org, willemdebruijn.kernel@gmail.com, skhawaja@google.com, kuba@kernel.org, Martin Karsten , Joe Damato , Alexander Viro , Christian Brauner , Jan Kara , linux-fsdevel@vger.kernel.org (open list:FILESYSTEMS (VFS and infrastructure)), linux-kernel@vger.kernel.org (open list) Subject: [PATCH net-next v8 3/6] eventpoll: Trigger napi_busy_loop, if prefer_busy_poll is set Date: Fri, 8 Nov 2024 04:53:25 +0000 Message-Id: <20241108045337.292905-4-jdamato@fastly.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20241108045337.292905-1-jdamato@fastly.com> References: <20241108045337.292905-1-jdamato@fastly.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Martin Karsten Setting prefer_busy_poll now leads to an effectively nonblocking iteration though napi_busy_loop, even when busy_poll_usecs is 0. Signed-off-by: Martin Karsten Co-developed-by: Joe Damato Signed-off-by: Joe Damato Tested-by: Joe Damato Tested-by: Martin Karsten Acked-by: Stanislav Fomichev Reviewed-by: Sridhar Samudrala --- v1 -> v2: - Rebased to apply now that commit b9ca079dd6b0 ("eventpoll: Annotate data-race of busy_poll_usecs") has been picked up from VFS. fs/eventpoll.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 1ae4542f0bd8..f9e0d9307dad 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -420,7 +420,9 @@ static bool busy_loop_ep_timeout(unsigned long start_time, static bool ep_busy_loop_on(struct eventpoll *ep) { - return !!READ_ONCE(ep->busy_poll_usecs) || net_busy_loop_on(); + return !!READ_ONCE(ep->busy_poll_usecs) || + READ_ONCE(ep->prefer_busy_poll) || + net_busy_loop_on(); } static bool ep_busy_loop_end(void *p, unsigned long start_time)