From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E06E2C11F69 for ; Wed, 30 Jun 2021 17:17:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BCBF561490 for ; Wed, 30 Jun 2021 17:17:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232482AbhF3RUS (ORCPT ); Wed, 30 Jun 2021 13:20:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36326 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229573AbhF3RUR (ORCPT ); Wed, 30 Jun 2021 13:20:17 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E575BC061756; Wed, 30 Jun 2021 10:17:47 -0700 (PDT) Received: from zn.tnic (p200300ec2f12c300d32a22941298d01c.dip0.t-ipconnect.de [IPv6:2003:ec:2f12:c300:d32a:2294:1298:d01c]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 4F3161EC046E; Wed, 30 Jun 2021 19:17:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1625073466; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=lZkWfm5u08oDdFUR6N+KHOvVmnsC24sm5yc+HxeB/CY=; b=ldHx2lzmiOHxUFziw6arVd4BG2SyN/yZtPY3lsNNSX+TrqizOvZUohfsFjCxugP2u5JEOw WHp4EICXAI/oleuPVK7/8WR5UUZDFmGdRM0Js4KjtoBeAF0b2X1viO9PZm6lWLAY0Jbv+A QODloyCYzYOjlXa+UX3sEF5oVUr5pZ8= Date: Wed, 30 Jun 2021 19:17:41 +0200 From: Borislav Petkov To: Yazen Ghannam Cc: linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org, mchehab@kernel.org, tony.luck@intel.com, Smita.KoralahalliChannabasappa@amd.com Subject: Re: [PATCH v2 05/31] EDAC/amd64: Add context struct Message-ID: References: <20210623192002.3671647-1-yazen.ghannam@amd.com> <20210623192002.3671647-6-yazen.ghannam@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210623192002.3671647-6-yazen.ghannam@amd.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 23, 2021 at 07:19:36PM +0000, Yazen Ghannam wrote: > Define an address translation context struct. This will hold values that > will be passed between multiple functions. > > Save return address, Node ID, and the Instance ID number to start. > Currently, we use the UMC number as the Instance ID, but future DF Please use passive voice in your commit message: no "we" or "I", etc. And this here is a perfect example: it sounds here like "we" is "AMD" but we use "we" mostly for the kernel. And there's the confusion. So please teach yourself to formulate those commit messages properly - the future you will thank you, trust me! :-) > versions may use another value. > > Signed-off-by: Yazen Ghannam > --- > Link: > https://lkml.kernel.org/r/20210507190140.18854-3-Yazen.Ghannam@amd.com > > v1->v2: > * Moved from arch/x86 to EDAC. > * Changed "umc" variable to "inst_id". > * Drop df_types enum. > > drivers/edac/amd64_edac.c | 49 +++++++++++++++++++++++++-------------- > 1 file changed, 31 insertions(+), 18 deletions(-) > > diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c > index d67cd8f57b94..62eca188458f 100644 > --- a/drivers/edac/amd64_edac.c > +++ b/drivers/edac/amd64_edac.c > @@ -1079,12 +1079,15 @@ static struct df_reg df_regs[] = { > [SYS_FAB_ID_MASK] = {1, 0x208}, > }; > > +struct addr_ctx { > + u64 ret_addr; > + u16 nid; > + u8 inst_id; > +}; > + > static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr) > { > u64 dram_base_addr, dram_limit_addr, dram_hole_base; > - /* We start from the normalized address */ > - u64 ret_addr = norm_addr; > - > u32 tmp; > > u8 die_id_shift, die_id_mask, socket_id_shift, socket_id_mask; > @@ -1097,6 +1100,16 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr > > struct df_reg reg; > > + struct addr_ctx ctx; Those empty-lines spaced-out local vars look weird. > + memset(&ctx, 0, sizeof(ctx)); > + > + /* We start from the normalized address */ > + ctx.ret_addr = norm_addr; > + > + ctx.nid = nid; > + ctx.inst_id = umc; > + > if (amd_df_indirect_read(nid, df_regs[DRAM_OFFSET], umc, &tmp)) > goto out_err; > > @@ -1105,7 +1118,7 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr > u64 hi_addr_offset = (tmp & GENMASK_ULL(31, 20)) << 8; > > if (norm_addr >= hi_addr_offset) { > - ret_addr -= hi_addr_offset; > + ctx.ret_addr -= hi_addr_offset; > base = 1; > } > } > @@ -1236,14 +1249,14 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr > * bits there are. "intlv_addr_bit" tells us how many "Y" bits > * there are (where "I" starts). > */ > - temp_addr_y = ret_addr & GENMASK_ULL(intlv_addr_bit-1, 0); > + temp_addr_y = ctx.ret_addr & GENMASK_ULL(intlv_addr_bit - 1, 0); > temp_addr_i = (cs_id << intlv_addr_bit); > - temp_addr_x = (ret_addr & GENMASK_ULL(63, intlv_addr_bit)) << num_intlv_bits; > - ret_addr = temp_addr_x | temp_addr_i | temp_addr_y; > + temp_addr_x = (ctx.ret_addr & GENMASK_ULL(63, intlv_addr_bit)) << num_intlv_bits; > + ctx.ret_addr = temp_addr_x | temp_addr_i | temp_addr_y; You want to align those vertically on the "=" for better readability. > } > > /* Add dram base address */ > - ret_addr += dram_base_addr; > + ctx.ret_addr += dram_base_addr; > > /* If legacy MMIO hole enabled */ > if (lgcy_mmio_hole_en) { > @@ -1251,29 +1264,29 @@ static int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr > goto out_err; > > dram_hole_base = tmp & GENMASK(31, 24); > - if (ret_addr >= dram_hole_base) > - ret_addr += (BIT_ULL(32) - dram_hole_base); > + if (ctx.ret_addr >= dram_hole_base) > + ctx.ret_addr += (BIT_ULL(32) - dram_hole_base); > } > > if (hash_enabled) { > /* Save some parentheses and grab ls-bit at the end. */ > - hashed_bit = (ret_addr >> 12) ^ > - (ret_addr >> 18) ^ > - (ret_addr >> 21) ^ > - (ret_addr >> 30) ^ > + hashed_bit = (ctx.ret_addr >> 12) ^ > + (ctx.ret_addr >> 18) ^ > + (ctx.ret_addr >> 21) ^ > + (ctx.ret_addr >> 30) ^ > cs_id; > > hashed_bit &= BIT(0); > > - if (hashed_bit != ((ret_addr >> intlv_addr_bit) & BIT(0))) > - ret_addr ^= BIT(intlv_addr_bit); > + if (hashed_bit != ((ctx.ret_addr >> intlv_addr_bit) & BIT(0))) > + ctx.ret_addr ^= BIT(intlv_addr_bit); > } > > /* Is calculated system address is above DRAM limit address? */ > - if (ret_addr > dram_limit_addr) > + if (ctx.ret_addr > dram_limit_addr) > goto out_err; > > - *sys_addr = ret_addr; > + *sys_addr = ctx.ret_addr; So adding ctx to exchange data between functions - that was a good idea. But what this patch does is pointless because you simply replace those variables with a local struct. I guess the aha moment will come with the later patches when you start passing it around to functions. /me waits to see. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette