Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754242AbdHUVtt (ORCPT ); Mon, 21 Aug 2017 17:49:49 -0400 Received: from mail-it0-f45.google.com ([209.85.214.45]:37892 "EHLO mail-it0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753600AbdHUVtk (ORCPT ); Mon, 21 Aug 2017 17:49:40 -0400 MIME-Version: 1.0 In-Reply-To: <1503349011.2042.168.camel@hpe.com> References: <20170818194644.14538-1-toshi.kani@hpe.com> <20170818194644.14538-2-toshi.kani@hpe.com> <20170821112657.hrtjoeagxhc67rrr@pd.tnic> <1503333107.2042.163.camel@hpe.com> <20170821170415.kttnqiwj2fkntsc7@pd.tnic> <1503335626.2042.165.camel@hpe.com> <20170821173612.i3zxlmxklmvv5kzd@pd.tnic> <1503349011.2042.168.camel@hpe.com> From: "Rafael J. Wysocki" Date: Mon, 21 Aug 2017 23:49:39 +0200 X-Google-Sender-Auth: L0dfPfxP01pD6odKmOJqPUeIrn8 Message-ID: Subject: Re: [PATCH v3 1/5] ACPI / blacklist: add acpi_match_platform_list() To: "Kani, Toshimitsu" Cc: "bp@alien8.de" , "rafael@kernel.org" , "linux-acpi@vger.kernel.org" , "lenb@kernel.org" , "mchehab@kernel.org" , "tony.luck@intel.com" , "linux-kernel@vger.kernel.org" , "linux-edac@vger.kernel.org" , "rjw@rjwysocki.net" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2331 Lines: 53 On Mon, Aug 21, 2017 at 11:06 PM, Kani, Toshimitsu wrote: > On Mon, 2017-08-21 at 22:31 +0200, Rafael J. Wysocki wrote: >> On Mon, Aug 21, 2017 at 7:36 PM, Borislav Petkov >> wrote: >> > On Mon, Aug 21, 2017 at 05:23:37PM +0000, Kani, Toshimitsu wrote: >> > > > > 'data' here is private to the caller. So, I do not think we >> > > > > need to define the bits. Shall I change the name to >> > > > > 'driver_data' to make it more explicit? >> > > > >> > > > You changed it to 'data'. It was a u32-used-as-boolean >> > > > is_critical_error before. >> > > > >> > > > So you can just as well make it into flags and people can >> > > > extend those flags if needed. A flag bit should be enough in >> > > > most cases anyway. If they really need driver_data, then they >> > > > can add a void *member. >> > > >> > > Hmm.. In patch 2, intel_pstate_platform_pwr_mgmt_exists() uses >> > > this field for PSS and PCC, which are enum values. I think we >> > > should allow drivers to set any values here. I agree that it may >> > > need to be void * if we also allow drivers to set a pointer here. >> > >> > Let's see what Rafael prefers. >> >> I would retain the is_critical_error field and use that for printing >> the recoverable / non-recoverable message. This is kind of >> orthogonal to whether or not any extra data is needed and that can be >> an additional field. In that case unsigned long should be sufficient >> to accommodate a pointer if need be. > > Yes, we will retain the field. The question is whether this field > should be retained as a driver's private data or ACPI-managed flags. Thanks for the clarification. > My patch implements the former, which lets the callers to define the > data values. For instance, acpi_blacklisted() uses this field as > is_critical_error value, and intel_pstate_platform_pwr_mgmt_exists() > uses it as oem_pwr_table value. > > Boris suggested the latter, which lets ACPI to define the flags, which > are then used by the callers. For instance, he suggested ACPI to > define bit0 as is_critical_error. > > #define ACPI_PLAT_IS_CRITICAL_ERROR BIT(0) So my point is that we can have both the ACPI-managed flags and the the caller-defined data at the same time as separate items. That would allow of maximum flexibility IMO. Thanks, Rafael