From mboxrd@z Thu Jan 1 00:00:00 1970 From: Davidlohr Bueso Subject: Re: [RFC PATCH-tip v4 10/10] locking/rwsem: Add a boot parameter to reader spinning threshold Date: Tue, 23 Aug 2016 21:00:07 -0700 Message-ID: <20160824040007.GA17186@linux-80c1.suse> References: <1471554672-38662-1-git-send-email-Waiman.Long@hpe.com> <1471554672-38662-11-git-send-email-Waiman.Long@hpe.com> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <1471554672-38662-11-git-send-email-Waiman.Long@hpe.com> Sender: linux-ia64-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" Content-Transfer-Encoding: 7bit To: Waiman Long Cc: Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, x86@kernel.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, Jason Low , Dave Chinner , Jonathan Corbet , Scott J Norton , Douglas Hatch On Thu, 18 Aug 2016, Waiman Long wrote: >The default reader spining threshold is current set to 4096. However, >the right reader spinning threshold may vary from one system to >another and among the different architectures. This patch adds a new >kernel boot parameter to modify the threshold value. This enables >better tailoring to the needs of different systems as well as for >testing purposes. It also means that those systems could very easily be incorrectly tailored. (and worse case scenario: reboot, is obviously a terrible way to get rid of any issues). I very much disagree with exposing this sort of core stuff, it should work well for everyone out of the box, not relying on users to properly configure this. Thanks, Davidlohr From mboxrd@z Thu Jan 1 00:00:00 1970 From: Davidlohr Bueso Date: Wed, 24 Aug 2016 04:00:07 +0000 Subject: Re: [RFC PATCH-tip v4 10/10] locking/rwsem: Add a boot parameter to reader spinning threshold Message-Id: <20160824040007.GA17186@linux-80c1.suse> List-Id: References: <1471554672-38662-1-git-send-email-Waiman.Long@hpe.com> <1471554672-38662-11-git-send-email-Waiman.Long@hpe.com> In-Reply-To: <1471554672-38662-11-git-send-email-Waiman.Long@hpe.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Waiman Long Cc: Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, x86@kernel.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, Jason Low , Dave Chinner , Jonathan Corbet , Scott J Norton , Douglas Hatch On Thu, 18 Aug 2016, Waiman Long wrote: >The default reader spining threshold is current set to 4096. However, >the right reader spinning threshold may vary from one system to >another and among the different architectures. This patch adds a new >kernel boot parameter to modify the threshold value. This enables >better tailoring to the needs of different systems as well as for >testing purposes. It also means that those systems could very easily be incorrectly tailored. (and worse case scenario: reboot, is obviously a terrible way to get rid of any issues). I very much disagree with exposing this sort of core stuff, it should work well for everyone out of the box, not relying on users to properly configure this. Thanks, Davidlohr