From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 25F0F2113DA1D for ; Mon, 17 Sep 2018 23:01:20 -0700 (PDT) Subject: [ndctl PATCH 0/3] ndctl: Remove udev rule for latch and dirty-shutdown-count From: Dan Williams Date: Mon, 17 Sep 2018 22:49:11 -0700 Message-ID: <153724975102.55312.9664009456306267501.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: linux-nvdimm@lists.01.org List-ID: The latch needs to be coordinated with writes to the namespace and that makes it not suitable as a dimm-add-event udev rule. Additionally, the dirty-shutdown-count is something that can live in sysfs alongside the other health state flags in /sys/.../nmemX/nfit. Otherwise, calling any of the libndctl apis from a udev script means the entire udev queue can get blocked behind a ndctl_bus_wait_probe() call. That's too much overhead for a non-default policy. In other words, while the latch event remains in userspace as close as possible to the application that wants to manage dimm-flush-failed policy as anything other than fatal, dirty-shutdown-count caching should move to sysfs where it is cheap to implement and compliments the flush-failed health state flag. --- Dan Williams (3): ndctl: Introduce dirty-dimm command ndctl: Revert "ndctl, intel: Fallback to smart cached shutdown_count" ndctl: Revert "ndctl: Create ndctl udev rules for dirty shutdown" .gitignore | 1 Documentation/ndctl/Makefile.am | 1 Documentation/ndctl/ndctl-dirty-dimm.txt | 29 ++++++ Makefile.am | 3 - builtin.h | 1 configure.ac | 10 -- contrib/80-ndctl.rules | 3 - ndctl.spec.in | 3 - ndctl/Makefile.am | 5 - ndctl/dimm.c | 28 ++++++ ndctl/lib/intel.c | 41 -------- ndctl/lib/libndctl.c | 6 - ndctl/lib/private.h | 3 - ndctl/ndctl-udev.c | 150 ------------------------------ ndctl/ndctl.c | 1 15 files changed, 61 insertions(+), 224 deletions(-) create mode 100644 Documentation/ndctl/ndctl-dirty-dimm.txt delete mode 100644 contrib/80-ndctl.rules delete mode 100644 ndctl/ndctl-udev.c _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm