From cth@sac.sfbay.sun.com Tue Aug 21 19:06:47 2007 Received: from sunmail2sca.sfbay.sun.com (sunmail2sca [129.145.155.234]) by sac.sfbay.sun.com (8.13.8+Sun/8.13.8) with ESMTP id l7M26lK0022152 for ; Tue, 21 Aug 2007 19:06:47 -0700 (PDT) Received: from brm-avmta-1.central.sun.com (brm-avmta-1.Central.Sun.COM [129.147.4.11]) by sunmail2sca.sfbay.sun.com (8.13.7+Sun/8.13.7/ENSMAIL,v2.2) with ESMTP id l7M24BlU005385; Tue, 21 Aug 2007 19:04:14 -0700 (PDT) Received: from pmxchannel-daemon.brm-avmta-1.central.sun.com by brm-avmta-1.central.sun.com (Sun Java System Messaging Server 6.2-3.04 (built Jul 15 2005)) id <0JN500N1HKF25900@brm-avmta-1.central.sun.com>; Tue, 21 Aug 2007 20:04:14 -0600 (MDT) Received: from sfbaymail2sca.sfbay.sun.com ([129.145.155.42]) by brm-avmta-1.central.sun.com (Sun Java System Messaging Server 6.2-3.04 (built Jul 15 2005)) with ESMTP id <0JN500H77KEZ3SF0@brm-avmta-1.central.sun.com>; Tue, 21 Aug 2007 20:04:12 -0600 (MDT) Received: from sac.sfbay.sun.com (new-sac.SFBay.Sun.COM [129.146.175.65]) by sfbaymail2sca.sfbay.sun.com (8.13.6+Sun/8.12.10/ENSMAIL,v2.2) with ESMTP id l7M24AHx024474; Tue, 21 Aug 2007 19:04:10 -0700 (PDT) Received: from sac.sfbay.sun.com (localhost [127.0.0.1]) by sac.sfbay.sun.com (8.13.8+Sun/8.13.8) with ESMTP id l7M26f4F022147; Tue, 21 Aug 2007 19:06:41 -0700 (PDT) Received: (from cth@localhost) by sac.sfbay.sun.com (8.13.8+Sun/8.13.8/Submit) id l7M26fmQ022143; Tue, 21 Aug 2007 19:06:41 -0700 (PDT) Date: Tue, 21 Aug 2007 19:06:41 -0700 (PDT) From: Christopher Horne Subject: Deletion of a KSTAT_FLAG_PERSISTENT kstat [PSARC/2007/478 FastTrack timeout 08/28/2007] To: PSARC-ext@sun.com Cc: Li.He@sun.com Message-id: <200708220206.l7M26fmQ022143@sac.sfbay.sun.com> Content-transfer-encoding: 7BIT X-PMX-Version: 5.2.0.264296 Status: RO Content-Length: 5530 I am submitting this fast-track on behalf of myself, with timeout set to 08/28/2007. Patch/update binding requesed. Template Version: @(#)sac_nextcase 1.64 07/13/07 SMI This information is Copyright 2007 Sun Microsystems 1. Introduction 1.1 Project/Component Working Name: Deletion of a KSTAT_FLAG_PERSISTENT kstat 1.2 Name of Document Author/Supplier: Author: Chris Horne 1.3 Date of This Document: Tue Jul 3 22:09:03 MDT 2007 4. Technical Description 4.1 Problem For a KSTAT_FLAG_PERSISTENT kstat is created by kstat_create(9F), a kstat_delete(9F) call does not completely destroy the kstat. This behavior means that kstat consumers can't fully controll which kstats a utility like iostat(1M) will still find and display. 4.2 Proposal This fasttrack defines a new kstat_destroy_persistent(9F) interface that can be used to completely destroy a kstat created with the KSTAT_FLAG_PERSISTENT. Some use cases for this interface are o When the association of a disk partition to a region of storage undergoes a fundamental change, a driver needs a way to completely delete kstats associated with the old partition. Some examples of such a situation are a change in the base block associated of a partition, or conversion of a disk from SUN label to/from an EFI label. o We have requests to support 'reset' of kstat data. In general the kstat implementation does not knows enough to perform the reset operation itself: not all initial values are guaranteed to be zero - esp for strings. A simple approach to reset would be for a target driver to completely delete its kstats, and then use common code recreate them. Current kstat_delete() behavior for KSTAT_FLAG_PERSISTENT kstats prevents this. 4.4 Interface Table ------------------------------------------------------------------------ Interface Level Comments ------------------------------------------------------------------------ kstat_delete_persistent() Committed delete a KSTAT_FLAG_PERSISTENT kstat 4.5 References [0] The kstat stability "best practice" http://sac.sfbay.sun.com/cgi-bin/bp.cgi?NAME=kstat.bp [1] PSARC 1992/085 /dev/statistics http://sac.sfbay/PSARC/1992/085 http://www.opensolaris.org/os/community/arc/caselog/1992/085 [2] PSARC 1996/273 64-bit neutral kstat http://sac.sfbay/PSARC/1996/273 http://www.opensolaris.org/os/community/arc/caselog/1996/273 [3] PSARC 1997/285 64-bit kstat revisited http://sac.sfbay/PSARC/1997/285 http://www.opensolaris.org/os/community/arc/caselog/1997/285 [4] PSARC 1999/495 kstat(1M) http://sac.sfbay/PSARC/1999/495 http://www.opensolaris.org/os/community/arc/caselog/1999/495 [5] PSARC 2000/053 ECC and Memory Configuration kstats http://sac.sfbay/PSARC/2000/053 [6] PSARC 2000/468 Optionally disable per-partition kstats http://sac.sfbay/PSARC/2000/468/ http://www.opensolaris.org/os/community/arc/caselog/2000/468 [7] PSARC/2001/239 KSTAT_DATA_STRING http://sac.sfbay/PSARC/2001/239/ http://www.opensolaris.org/os/community/arc/caselog/2001/239 4.6 Man page changes See below. 6. Resources and Schedule 6.4 Steering Committee requested information 6.4.1 Consolidation C-team Name: ON 6.5 ARC review type: FastTrack A.1 Proposed kstat_delete(9F) man page changes: Kernel Functions for Drivers kstat_delete(9F) NAME | kstat_delete, kstat_delete_persistent - remove a kstat from the system SYNOPSIS #include #include void kstat_delete(kstat_t *ksp); | void kstat_delete_persistent(kstat_t *ksp); INTERFACE LEVEL Solaris DDI specific (Solaris DDI) PARAMETERS ksp Pointer to a currently installed kstat(9S) struc- ture. DESCRIPTION | A kstat is either persistent or non-persistent depending on | whether kstat_create(9F) used the KSTAT_FLAG_PERSISTENT. | | For non-persistent kstats, kstat_delete() removes ksp from the | kstat chain and frees all associated system resources. | | For persistent kstats, kstat_delete(9F) simply marks the kstat | as dormant; a subsequent kstat_create() reactivates the | kstat. To fully delete a persistent kstat, use | kstat_delete_persistent. RETURN VALUES None. CONTEXT | kstat_delete() and kstat_delete_persistent() can be called from any | context. SEE ALSO kstat_create(9F), kstat_install(9F), kstat_named_init(9F), kstat(9S) Writing Device Drivers | NOTES When calling kstat_delete() or kstat_delete_persistent(), the driver must not be holding that kstat's ks_lock. Otherwise, it may deadlock with a kstat reader. 6. Resources and Schedule 6.4. Steering Committee requested information 6.4.1. Consolidation C-team Name: ON 6.5. ARC review type: FastTrack 6.6. ARC Exposure: open From Chris.Horne@sun.com Wed Aug 29 12:52:54 2007 Received: from sunmail5.uk.sun.com (sunmail5.UK.Sun.COM [129.156.85.165]) by sac.sfbay.sun.com (8.13.8+Sun/8.13.8) with ESMTP id l7TJqraA023321 for ; Wed, 29 Aug 2007 12:52:54 -0700 (PDT) Received: from nwk-avmta-2.sfbay.sun.com (nwk-avmta-2.SFBay.Sun.COM [129.145.155.6]) by sunmail5.uk.sun.com (8.13.7+Sun/8.13.7/ENSMAIL,v2.2) with ESMTP id l7TJo17I007312 for <@sunmail2sca.sfbay.sun.com:PSARC-ext@sun.com>; Wed, 29 Aug 2007 20:50:14 +0100 (BST) Received: from pmxchannel-daemon.nwk-avmta-2.sfbay.sun.com by nwk-avmta-2.sfbay.sun.com (Sun Java System Messaging Server 6.2-3.04 (built Jul 15 2005)) id <0JNJ00C05WFOEW00@nwk-avmta-2.sfbay.sun.com> for PSARC-ext@sun.com (ORCPT PSARC-ext@Sun.COM); Wed, 29 Aug 2007 12:50:12 -0700 (PDT) Received: from brmea-mail-1.sun.com ([192.18.98.31]) by nwk-avmta-2.sfbay.sun.com (Sun Java System Messaging Server 6.2-3.04 (built Jul 15 2005)) with ESMTP id <0JNJ006SHWFN1170@nwk-avmta-2.sfbay.sun.com> for PSARC-ext@sun.com (ORCPT PSARC-ext@Sun.COM); Wed, 29 Aug 2007 12:50:11 -0700 (PDT) Received: from fe-amer-06.sun.com ([192.18.108.180]) by brmea-mail-1.sun.com (8.13.6+Sun/8.12.9) with ESMTP id l7TJo7JQ003842 for ; Wed, 29 Aug 2007 19:50:07 +0000 (GMT) Received: from conversion-daemon.mail-amer.sun.com by mail-amer.sun.com (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) id <0JNJ00B01W7HS000@mail-amer.sun.com> (original mail from Chris.Horne@Sun.COM) for PSARC-ext@Sun.COM (ORCPT PSARC-ext@Sun.COM); Wed, 29 Aug 2007 13:50:07 -0600 (MDT) Received: from [172.20.25.50] by mail-amer.sun.com (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPSA id <0JNJ001A3WF7QDEB@mail-amer.sun.com> for PSARC-ext@Sun.COM (ORCPT PSARC-ext@Sun.COM); Wed, 29 Aug 2007 13:49:56 -0600 (MDT) Date: Wed, 29 Aug 2007 13:46:27 -0600 From: Chris Horne Subject: Re: Deletion of a KSTAT_FLAG_PERSISTENT kstat [PSARC/2007/478 FastTrack timeout 08/28/2007] In-reply-to: <200708220206.l7M26fmQ022143@sac.sfbay.sun.com> Sender: Chris.Horne@sun.com To: PSARC-ext@sun.com Cc: Li.He@sun.com Message-id: <46D5CD13.6050707@sun.com> MIME-version: 1.0 Content-type: text/plain; format=flowed; charset=ISO-8859-1 Content-transfer-encoding: 7BIT X-PMX-Version: 5.2.0.264296 References: <200708220206.l7M26fmQ022143@sac.sfbay.sun.com> User-Agent: Thunderbird 1.5.0.8 (X11/20061204) Status: RO Content-Length: 141 > 1.1 Project/Component Working Name: > Deletion of a KSTAT_FLAG_PERSISTENT kstat This case was approved at today's PSARC meeting. -Chris