From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f44.google.com (mail-io1-f44.google.com [209.85.166.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 894D546BA6 for ; Tue, 18 Jun 2024 20:58:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718744329; cv=none; b=nWjDSfSLJhykmsaRFgqlSXI0+s8rL80IUDaznwlWREfc0HO0jpKW7NBDO8RsWVSBKIZr9GBgvhtUGRKcA71ohWHTfhxABOJpNDVOFzaDoNJEQyB9hJJtTcHAyGaFqRIfJnWHlvB0eR/sQfD6adCiImQLWOdd7bVPbK/nYcGql4s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718744329; c=relaxed/simple; bh=GL4WG3gGiRy5iVYQEdrg+YE9pgM649jZLwWBiNBLnAA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hNiFX4FaG1k0pbaqSjCyKlG3mXsiRNmx0kIpxykY7OBGRL0qEipyJgwO12yef9QvrmNbSAmt8VHqtOTzVAb7au1f/8gYpAPn8iaaMOHUuyL9OGJhZOqLBn/iL3j/71nh5fxtdLHzJPj1nktQ2/LM6ZHjjtykf6hMkWFv8cvoy+w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kfocus.org; spf=pass smtp.mailfrom=kfocus.org; dkim=pass (2048-bit key) header.d=kfocus-org.20230601.gappssmtp.com header.i=@kfocus-org.20230601.gappssmtp.com header.b=nfP/ZnBS; arc=none smtp.client-ip=209.85.166.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kfocus.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kfocus.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kfocus-org.20230601.gappssmtp.com header.i=@kfocus-org.20230601.gappssmtp.com header.b="nfP/ZnBS" Received: by mail-io1-f44.google.com with SMTP id ca18e2360f4ac-7eb5dd9f994so231536239f.2 for ; Tue, 18 Jun 2024 13:58:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kfocus-org.20230601.gappssmtp.com; s=20230601; t=1718744327; x=1719349127; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=V5fTw4oIChX/XVGvVrvDmot1CuQjy9wAr2Jw7V0wyH4=; b=nfP/ZnBSgOuujYLsjEgZkwCqLonrPCRytasRpKRJMFmzx1AHzDuf/zM0tBcsUZt4Q2 HM4zvMl9KlobFjcf4CfnB1VZvbhzYm00OPpSa+auwO+7KybSi01my25uPLq1DKVOXIe8 v4wuwSdwNe9Z/ueHYbHFoCFH3L9EtZu9c5PkdlNAeTR/7q6Sh/FT6d1sFmZsNDM+Q32j Lg18hOo3Pozmic6wbfw02piX54g6/JRhzMbKpFXpjQjurDOEVOaTgwJxxpRl/LHv70nF 588FmgtSpxfzi3MQRy2I1w8wzOQ3UDw4r7bR1PIMQE+cNJwcYndoPf+dhTYwJ1wESmV7 bigg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718744327; x=1719349127; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=V5fTw4oIChX/XVGvVrvDmot1CuQjy9wAr2Jw7V0wyH4=; b=BLTPQVFxpNSFEFmWXyfl4iaisqMeB5Aqni1BnG+yiwSw5ADwU15Of3QPXzWq5sQJoR V0mpCDCme0Us/C9f48+SFN4QCWIsqimndNqeuB6eawYoJaXn9sD3dUM7YDZHtvq7Zttn e8u35hkNT84o4FUw0TKmXl8CApUMCTM2ax0617dGP7ho/ISyQXQqtnjEKqbB6KJWDHVX gKWxQ7ByrO81/SDfZ0axHQenIIWzMlEQ3nulmcOZ/1Eg69oskm75uuUs+JLVnXAeqoQ+ +KvPYzKk9wn62B1bqBo9VjAOaTJeTuYVKRAHABwZR3oW0FwhzvkiK+rPKw/nZJ2hCfMc IOZw== X-Forwarded-Encrypted: i=1; AJvYcCUJ2LFdpZPStizpzIgt+dkMY6dfpQz/PqAE3LDZBPo26b2mxmjpd1Lp8URLkHPcUXwQWmLsun6rVBhmbguYpwnhWmMAHqd1DyhpnA== X-Gm-Message-State: AOJu0YwKl0rwzIUw6B3y/aCaBTaQVkG1LqWVhkL4fqZ7OKdNpw9Ad13l s5e0lcP29o9U/+3m4bJia2yy0VZO1yrRZmEfEHt8jWTlpAdh0LAplmXBQEC50f0= X-Google-Smtp-Source: AGHT+IH+yRumAclbJinwAffvWd8nRl0WF/o33t8ouaYeI1M5L7Oo53VGMyQECDT4PGd6eSp9S8KX8Q== X-Received: by 2002:a05:6602:6415:b0:7eb:6a37:89ce with SMTP id ca18e2360f4ac-7f13ee875b0mr126392339f.14.1718744327667; Tue, 18 Jun 2024 13:58:47 -0700 (PDT) Received: from kf-XE ([2607:fb91:111c:4643:b5f:d6ad:8a73:5578]) by smtp.gmail.com with ESMTPSA id 8926c6da1cb9f-4b95d3e7fd2sm3113958173.157.2024.06.18.13.58.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jun 2024 13:58:47 -0700 (PDT) Date: Tue, 18 Jun 2024 15:58:44 -0500 From: Aaron Rainbolt To: mario.limonciello@amd.com, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: rafael@kernel.org, lenb@kernel.org, mmikowski@kfocus.org, Perry.Yuan@amd.com Subject: Re: [PATCH V2 RFC] acpi: Allow ignoring _OSC CPPC v2 bit via kernel parameter Message-ID: References: Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Jun 18, 2024 at 03:25:36PM -0500, Aaron Rainbolt wrote: > acpi: Allow ignoring _OSC CPPC v2 bit via kernel parameter > > The _OSC is supposed to contain a bit indicating whether the hardware > supports CPPC v2 or not. This bit is not always set, causing CPPC v2 to > be considered absent. This results in severe single-core performance > issues with the EEVDF scheduler on heterogenous-core Intel processors. > > To work around this, provide a new kernel parameter, "ignore_osc_cppc_bit", > which may be used to ignore the _OSC CPPC v2 bit and act as if the bit was > enabled. This allows CPPC to be properly detected even if not "enabled" by > _OSC, allowing users with problematic hardware to obtain decent single-core > performance. > > Signed-off-by: Aaron Rainbolt > > --- > > V1 -> V2: Rewrite to work in cpc_supported_by_cpu. > > RFC: I have not yet tested this patch to ensure it functions properly, > nor have I attempted to compile it against mainline. My system takes > a couple of hours or so to build a kernel, and I'd like to submit this > for feedback now and test once it's sent. I sped up my build by using a defconfig rather than a default menuconfig (still learning how these things work), and confirmed that the patch does build against 6.10~rc4. Will report back test results hopefully soon.