From patchwork Sun Feb 6 15:48:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Walt Drummond X-Patchwork-Id: 12736613 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E56DC433F5 for ; Sun, 6 Feb 2022 15:59:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240663AbiBFP7u (ORCPT ); Sun, 6 Feb 2022 10:59:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240660AbiBFP7t (ORCPT ); Sun, 6 Feb 2022 10:59:49 -0500 X-Greylist: delayed 512 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Sun, 06 Feb 2022 07:59:49 PST Received: from talisker.home.drummond.us (drummond.us [74.95.14.229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B864C06173B for ; Sun, 6 Feb 2022 07:59:48 -0800 (PST) Received: from talisker.home.drummond.us (localhost [127.0.0.1]) by talisker.home.drummond.us (8.15.2/8.15.2/Debian-20) with ESMTP id 216Fn9HY2355931; Sun, 6 Feb 2022 07:49:09 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=home.drummond.us; s=default; t=1644162549; bh=lh62Ew6xc+1J56dda/HpT63a00cvbUs7Fsz625WMbNo=; h=From:To:Cc:Subject:Date:From; b=IMvAAykX2zxhJdzSUi0tXykKGnnaIw9PnTefGLd/FLsa7mUt+ApvNnkAxjiOG8CF2 UlzPW6Xir5kCCxWqfEYN3bIysHzhkbkxqZusgCedJCPZpR4o4Wb9ogF4kWDlkyeDok LYTlYz986m951X3ZrowlNl0r0VwywtHKololqrw2XNSuGipoLq/s7ikn04KsKL39ad cghaP14NzAPk6+6NHZRQNYCkgXjNw40CyY51sGcQ4cQ0Jz7V27lPAVlzAd+Dvjlk4C ETy1ibTEQwbii5XPOQWd239kGFK+1TUd3H++9y9iz3njdjgvynb9MImSqqhM8JhwF+ VSCoxgC9Bxkaw== Received: (from walt@localhost) by talisker.home.drummond.us (8.15.2/8.15.2/Submit) id 216Fn0TW2355912; Sun, 6 Feb 2022 07:49:00 -0800 From: Walt Drummond To: agordeev@linux.ibm.com, arnd@arndb.de, benh@kernel.crashing.org, borntraeger@de.ibm.com, chris@zankel.net, davem@davemloft.net, gregkh@linuxfoundation.org, hca@linux.ibm.com, deller@gmx.de, ink@jurassic.park.msu.ru, James.Bottomley@HansenPartnership.com, jirislaby@kernel.org, mattst88@gmail.com, jcmvbkbc@gmail.com, mpe@ellerman.id.au, paulus@samba.org, rth@twiddle.net, dalias@libc.org, tsbogend@alpha.franken.de, gor@linux.ibm.com, ysato@users.osdn.me Cc: linux-kernel@vger.kernel.org, ar@cs.msu.ru, walt@drummond.us, linux-alpha@vger.kernel.org, linux-arch@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-xtensa@linux-xtensa.org, sparclinux@vger.kernel.org Subject: [PATCH v2 0/3] vstatus: TTY status message request Date: Sun, 6 Feb 2022 07:48:51 -0800 Message-Id: <20220206154856.2355838-1-walt@drummond.us> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org This patchset adds TTY status message request feature to the n_tty line dicipline. This feature prints a brief message containing basic system and process group information to a user's TTY in response to a new control character in the line dicipline (default Ctrl-T) or the TIOCSTAT ioctl. The message contains the current system load, the name and PID of an interesting process in the forground process group, it's run time, percent CPU usage and RSS. An example of this message is: load: 0.31 cmd: sleep 3616843 [sleeping] 0.36r 0.00u 0.00s 0% 696k This feature is in many other Unix systems, both current and historical. In other implementations, this feature would also send SIGINFO to the process group; this implementation does not. User API visible changes are limited to: - The addition of VSTATUS in termios.c_cc[] - The addition of NOKERNINFO bit in termios.l_cflags - The addition of the TIOCSTAT ioctl number None of these changes break the existing kernel api as the termios structure on all architectures has enough space in the control character array (.c_cc) for the new character. Walt Drummond (3): vstatus: Allow the n_tty line dicipline to write to a user tty status: Add user space API definitions for VSTATUS, NOKERNINFO and TIOCSTAT vstatus: Display an informational message when the VSTATUS character is pressed or TIOCSTAT ioctl is called. arch/alpha/include/asm/termios.h | 4 +- arch/alpha/include/uapi/asm/ioctls.h | 1 + arch/alpha/include/uapi/asm/termbits.h | 2 + arch/ia64/include/asm/termios.h | 4 +- arch/ia64/include/uapi/asm/termbits.h | 2 + arch/mips/include/asm/termios.h | 4 +- arch/mips/include/uapi/asm/ioctls.h | 1 + arch/mips/include/uapi/asm/termbits.h | 2 + arch/parisc/include/asm/termios.h | 4 +- arch/parisc/include/uapi/asm/ioctls.h | 1 + arch/parisc/include/uapi/asm/termbits.h | 2 + arch/powerpc/include/asm/termios.h | 4 +- arch/powerpc/include/uapi/asm/ioctls.h | 2 + arch/powerpc/include/uapi/asm/termbits.h | 2 + arch/s390/include/asm/termios.h | 4 +- arch/sh/include/uapi/asm/ioctls.h | 1 + arch/sparc/include/uapi/asm/ioctls.h | 1 + arch/sparc/include/uapi/asm/termbits.h | 2 + arch/xtensa/include/uapi/asm/ioctls.h | 1 + drivers/tty/Makefile | 2 +- drivers/tty/n_tty.c | 103 +++++++++---- drivers/tty/n_tty_status.c | 181 +++++++++++++++++++++++ drivers/tty/tty_io.c | 2 +- include/asm-generic/termios.h | 4 +- include/linux/tty.h | 7 +- include/uapi/asm-generic/ioctls.h | 1 + include/uapi/asm-generic/termbits.h | 2 + 27 files changed, 301 insertions(+), 45 deletions(-) create mode 100644 drivers/tty/n_tty_status.c