From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6F4AFC48285 for ; Thu, 25 Jan 2024 22:31:11 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rT8EK-0007WE-VY; Thu, 25 Jan 2024 17:29:53 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rT8EI-0007Vp-I6; Thu, 25 Jan 2024 17:29:50 -0500 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rT8EG-0001x1-OG; Thu, 25 Jan 2024 17:29:50 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 4BDC447562; Fri, 26 Jan 2024 01:30:29 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id A85B26BA52; Fri, 26 Jan 2024 01:29:42 +0300 (MSK) Received: (nullmailer pid 147065 invoked by uid 1000); Thu, 25 Jan 2024 22:29:42 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-trivial@nongnu.org, Michael Tokarev Subject: [PATCH trivial 0/2] split out os_close_all_open_fd and use it in net/tap.c too Date: Fri, 26 Jan 2024 01:29:34 +0300 Message-Id: X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org We have at least two places in qemu where we're closing all possible file descriptors, - in async-teardown.c and in net/tap.c. While async-teardown one uses either close_range() or readdir(/proc/self/fd), the two calls in net/tap.c loops from 3 to RLIMIT_NOFILE, which might be quite slow, and it actually *is* slow on some systems (eg, just qemu-system-x86_64 startup with a tap device is very slow on alpine linux). While for net/tap.c, maybe the better fix is to get rid of this closing entirely and use O_CLOEXEC instead, this needs to be prepared at first, while we alredy have almost ready-to-be-used implementation which only needs to be moved into a common place. Michael Tokarev (2): close_all_open_fd(): move to oslib-posix.c net/tap: use os_close_all_open_fd() instead of open-coding it include/sysemu/os-posix.h | 1 + net/tap.c | 15 ++------------- system/async-teardown.c | 37 +------------------------------------ util/oslib-posix.c | 36 ++++++++++++++++++++++++++++++++++++ 4 files changed, 40 insertions(+), 49 deletions(-) -- 2.39.2