From owner-svn-src-all@freebsd.org Thu Jun 6 17:57:34 2019 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 18A2015BB0AE; Thu, 6 Jun 2019 17:57:34 +0000 (UTC) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (br1.CN84in.dnsmgr.net [69.59.192.140]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 8C52377E32; Thu, 6 Jun 2019 17:57:33 +0000 (UTC) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (localhost [127.0.0.1]) by gndrsh.dnsmgr.net (8.13.3/8.13.3) with ESMTP id x56HvU3t058979; Thu, 6 Jun 2019 10:57:30 -0700 (PDT) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: (from freebsd@localhost) by gndrsh.dnsmgr.net (8.13.3/8.13.3/Submit) id x56HvU51058978; Thu, 6 Jun 2019 10:57:30 -0700 (PDT) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <201906061757.x56HvU51058978@gndrsh.dnsmgr.net> Subject: Re: svn commit: r348737 - head/sys/kern In-Reply-To: To: Alan Somers Date: Thu, 6 Jun 2019 10:57:30 -0700 (PDT) CC: "Rodney W. Grimes" , src-committers , svn-src-all , svn-src-head Reply-To: rgrimes@freebsd.org X-Mailer: ELM [version 2.4ME+ PL121h (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII X-Rspamd-Queue-Id: 8C52377E32 X-Spamd-Bar: ------ Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-6.98 / 15.00]; REPLY(-4.00)[]; NEURAL_HAM_SHORT(-0.99)[-0.988,0]; NEURAL_HAM_MEDIUM(-1.00)[-0.996,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 06 Jun 2019 17:57:34 -0000 [ Charset UTF-8 unsupported, converting... ] > On Thu, Jun 6, 2019 at 11:35 AM Rodney W. Grimes > wrote: > > > > > Author: asomers > > > Date: Thu Jun 6 15:04:50 2019 > > > New Revision: 348737 > > > URL: https://svnweb.freebsd.org/changeset/base/348737 > > > > > > Log: > > > Add a testing facility to manually reclaim a vnode > > > > > > Add the debug.try_reclaim_vnode sysctl. When a pathname is written to it, it > > > will be reclaimed, as long as it isn't already or doomed. The purpose is to > > > gain test coverage for vnode reclamation, which is otherwise hard to > > > achieve. > > > > > > Add the debug.ftry_reclaim_vnode sysctl. It does the same thing, except > > > that its argument is a file descriptor instead of a pathname. > > > > Should not this all be wrapped in some #ifdef or other protection, > > is it really a good idea to have this on every single box running > > FreeBSD? > > I initially thought so too, but kib thought that it could be useful > for debugging problems in the field. The potential downside is > limited, because only root can write to the sysctls, and the > worse-case damage is similar to a "umount -f". Things that are useful for diagnostics and debugging do not belong on all production machines. I could live with INVARIANTS so it is only in all ^/head machines, but imho shipping this type of stuff in -RELEASE is not a good idea. > -Alan -- Rod Grimes rgrimes@freebsd.org