From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 991766087A; Fri, 2 Feb 2024 09:05:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706864751; cv=none; b=BO/lOa15XpwKGcuxUUOCrR4RJ34oOC7ZAcEUPvPNNlZR8zkmnwe3QtT4kQinKQZI2snAbiMESlhMukmL5bSFp2MsM4eBCqI+vhXYPD3KYqgwvajPoZZJWiAjegOyE966NAmmirEzpvVG73A7Yb6J4AvJFetI+8KFE9fwO0lMuJ8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706864751; c=relaxed/simple; bh=IKxvwNSUt3agfDzeeYKFG24bjgt9QnYU/2DpLutNLhM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=V1MRGygqHam3URTJ0CqPtOrtnW7YYFH1CcL6LELr3jBc2zFgQ/3sNE3Q6SopyNuo6ppAa2tvfPWVMTNEnoUIhWQDO1mesJJgQJXr4Orai8tQ/VkqS2pJoiZdCWDPj2PAqsxlWs5hkz165lsWXkOUzIpoGv/d3RXhH9TN45va7lc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5F9EADA7; Fri, 2 Feb 2024 01:06:30 -0800 (PST) Received: from e129154.nice.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 658B93F5A1; Fri, 2 Feb 2024 01:05:42 -0800 (PST) Date: Fri, 2 Feb 2024 10:05:05 +0100 From: Beata Michalska To: "Rafael J. Wysocki" Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, sumitg@nvidia.com, sudeep.holla@arm.covm, will@kernel.org, catalin.marinas@arm.com, viresh.kumar@linaro.org, ionela.voinescu@arm.com, yang@os.amperecomputing.com, linux-tegra@vger.kernel.org Subject: Re: [PATCH v2 2/2] cpufreq: Wire-up arch-flavored freq info into cpufreq_verify_current_freq Message-ID: References: <20231127160838.1403404-1-beata.michalska@arm.com> <20231127160838.1403404-3-beata.michalska@arm.com> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Apologies for extremely late reply, juggling too many things at time .... On Wed, Dec 06, 2023 at 09:41:05PM +0100, Rafael J. Wysocki wrote: > On Mon, Nov 27, 2023 at 5:09 PM Beata Michalska wrote: > > > > From: Sumit Gupta > > > > When available, use arch_freq_get_on_cpu to obtain current frequency > > (usually an average reported over given period of time) > > to better align the cpufreq's view on the current state of affairs. > > And why is this a good idea? Apart from being problematic with an issue pointed at [1] (which will result in dropping the change in cpufreq) this was to keep the cpufreq core aware of potential frequency changes and take appropriate action (informing the governor) case it got out of sync. > > Any problem statement? The problem has been raised here [2] > > > This also automatically pulls in the update for cpuinfo_cur_freq sysfs > > attribute, aligning it with the scaling_cur_freq one, and thus providing > > consistent view on relevant platforms. > > I have no idea what the above is supposed to mean, sorry. Bad wording I guess. With this change both 'cpuinfo_cur_freq' and 'scaling_cur_freq' will use the arch_freq_get_on_cpu if available, and will use the same source of information (one depending on a platform). > > > Signed-off-by: Sumit Gupta > > [BM: Subject & commit msg] > > Signed-off-by: Beata Michalska > > --- > > drivers/cpufreq/cpufreq.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > > index 8c4f9c2f9c44..109559438f45 100644 > > --- a/drivers/cpufreq/cpufreq.c > > +++ b/drivers/cpufreq/cpufreq.c > > @@ -1756,7 +1756,8 @@ static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, b > > { > > unsigned int new_freq; > > > > - new_freq = cpufreq_driver->get(policy->cpu); > > + new_freq = arch_freq_get_on_cpu(policy->cpu); > > + new_freq = new_freq ?: cpufreq_driver->get(policy->cpu); > > Please don't use ?: in general and it is not even useful here AFAICS. > > What would be wrong with > > new_freq = arch_freq_get_on_cpu(policy->cpu); > if (!new_freq) > new_freq = cpufreq_driver->get(policy->cpu); > > ? Nothing wrong with that. --- [1] https://lore.kernel.org/all/ZWXy0h%2FfFfQh+Rhy@arm.com/ [2] https://lore.kernel.org/lkml/6a5710f6-bfbb-5dfd-11cd-0cd02220cee7@nvidia.com/ --- BR Beata > > > if (!new_freq) > > return 0; > > > > -- 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3D806C4828E for ; Fri, 2 Feb 2024 09:06:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=zwujZVhPbBfeBc2b2kWKeUy4kEFTcZEoxJo2DmJWtxM=; b=ZB1hxGrPWyADNQ JF61/Y9o1Pkpd2JxbPNNT4EanE6wNcvwo9E4r2K2WCliuWH3N3XCQ+UJ1+15VE3aJXgV/0G2ITX9y QFyn+FWkI+lgyvQcCWc1VfjL5U7zHxpR1z6KG5E1fMTdIk5+y9kiApG2zIbtetCnilW7qrlbQ/M34 x2eu7ATKfNq9T+M8FKf1VcRR3OSpIRP62FD1NXT13MnS2JggQgPO8tYxcWWYDIgUx9E8fe+Yqrquc o0JuGpj/Dr+HbTVEEH9fQ3iLJkH1wIyp6FYN9CTiG1rfd3XTWEikTX4yek3R46l/H/hDBGfFIdnzO 0xjmIu9DYSah0Z2XQP4A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rVpUh-0000000AsaY-3DZr; Fri, 02 Feb 2024 09:05:55 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rVpUe-0000000AsYh-2hKS for linux-arm-kernel@lists.infradead.org; Fri, 02 Feb 2024 09:05:54 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5F9EADA7; Fri, 2 Feb 2024 01:06:30 -0800 (PST) Received: from e129154.nice.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 658B93F5A1; Fri, 2 Feb 2024 01:05:42 -0800 (PST) Date: Fri, 2 Feb 2024 10:05:05 +0100 From: Beata Michalska To: "Rafael J. Wysocki" Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, sumitg@nvidia.com, sudeep.holla@arm.covm, will@kernel.org, catalin.marinas@arm.com, viresh.kumar@linaro.org, ionela.voinescu@arm.com, yang@os.amperecomputing.com, linux-tegra@vger.kernel.org Subject: Re: [PATCH v2 2/2] cpufreq: Wire-up arch-flavored freq info into cpufreq_verify_current_freq Message-ID: References: <20231127160838.1403404-1-beata.michalska@arm.com> <20231127160838.1403404-3-beata.michalska@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240202_010552_755485_7953DF50 X-CRM114-Status: GOOD ( 27.27 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org QXBvbG9naWVzIGZvciBleHRyZW1lbHkgbGF0ZSByZXBseSwganVnZ2xpbmcgdG9vIG1hbnkgdGhp bmdzIGF0IHRpbWUgLi4uLgoKT24gV2VkLCBEZWMgMDYsIDIwMjMgYXQgMDk6NDE6MDVQTSArMDEw MCwgUmFmYWVsIEouIFd5c29ja2kgd3JvdGU6Cj4gT24gTW9uLCBOb3YgMjcsIDIwMjMgYXQgNTow OeKAr1BNIEJlYXRhIE1pY2hhbHNrYSA8YmVhdGEubWljaGFsc2thQGFybS5jb20+IHdyb3RlOgo+ ID4KPiA+IEZyb206IFN1bWl0IEd1cHRhIDxzdW1pdGdAbnZpZGlhLmNvbT4KPiA+Cj4gPiBXaGVu IGF2YWlsYWJsZSwgdXNlIGFyY2hfZnJlcV9nZXRfb25fY3B1IHRvIG9idGFpbiBjdXJyZW50IGZy ZXF1ZW5jeQo+ID4gKHVzdWFsbHkgYW4gYXZlcmFnZSByZXBvcnRlZCBvdmVyIGdpdmVuIHBlcmlv ZCBvZiB0aW1lKQo+ID4gdG8gYmV0dGVyIGFsaWduIHRoZSBjcHVmcmVxJ3MgdmlldyBvbiB0aGUg Y3VycmVudCBzdGF0ZSBvZiBhZmZhaXJzLgo+IAo+IEFuZCB3aHkgaXMgdGhpcyBhIGdvb2QgaWRl YT8KQXBhcnQgZnJvbSBiZWluZyBwcm9ibGVtYXRpYyB3aXRoIGFuIGlzc3VlIHBvaW50ZWQgYXQg WzFdICh3aGljaCB3aWxsIHJlc3VsdAppbiBkcm9wcGluZyB0aGUgY2hhbmdlIGluIGNwdWZyZXEp IHRoaXMgd2FzIHRvIGtlZXAgdGhlIGNwdWZyZXEgY29yZSBhd2FyZSBvZgpwb3RlbnRpYWwgZnJl cXVlbmN5IGNoYW5nZXMgYW5kIHRha2UgYXBwcm9wcmlhdGUgYWN0aW9uIChpbmZvcm1pbmcgdGhl IGdvdmVybm9yKQpjYXNlIGl0IGdvdCBvdXQgb2Ygc3luYy4KPiAKPiBBbnkgcHJvYmxlbSBzdGF0 ZW1lbnQ/ClRoZSBwcm9ibGVtIGhhcyBiZWVuIHJhaXNlZCBoZXJlIFsyXQo+IAo+ID4gVGhpcyBh bHNvIGF1dG9tYXRpY2FsbHkgcHVsbHMgaW4gdGhlIHVwZGF0ZSBmb3IgY3B1aW5mb19jdXJfZnJl cSBzeXNmcwo+ID4gYXR0cmlidXRlLCBhbGlnbmluZyBpdCB3aXRoIHRoZSBzY2FsaW5nX2N1cl9m cmVxIG9uZSwgYW5kIHRodXMgcHJvdmlkaW5nCj4gPiBjb25zaXN0ZW50IHZpZXcgb24gcmVsZXZh bnQgcGxhdGZvcm1zLgo+IAo+IEkgaGF2ZSBubyBpZGVhIHdoYXQgdGhlIGFib3ZlIGlzIHN1cHBv c2VkIHRvIG1lYW4sIHNvcnJ5LgpCYWQgd29yZGluZyBJIGd1ZXNzLiBXaXRoIHRoaXMgY2hhbmdl IGJvdGggJ2NwdWluZm9fY3VyX2ZyZXEnIGFuZAonc2NhbGluZ19jdXJfZnJlcScgd2lsbCB1c2Ug dGhlIGFyY2hfZnJlcV9nZXRfb25fY3B1IGlmIGF2YWlsYWJsZSwgYW5kIHdpbGwgdXNlCnRoZSBz YW1lIHNvdXJjZSBvZiBpbmZvcm1hdGlvbiAob25lIGRlcGVuZGluZyBvbiBhIHBsYXRmb3JtKS4K Cj4gCj4gPiBTaWduZWQtb2ZmLWJ5OiBTdW1pdCBHdXB0YSA8c3VtaXRnQG52aWRpYS5jb20+Cj4g PiBbQk06IFN1YmplY3QgJiBjb21taXQgbXNnXQo+ID4gU2lnbmVkLW9mZi1ieTogQmVhdGEgTWlj aGFsc2thIDxiZWF0YS5taWNoYWxza2FAYXJtLmNvbT4KPiA+IC0tLQo+ID4gIGRyaXZlcnMvY3B1 ZnJlcS9jcHVmcmVxLmMgfCAzICsrLQo+ID4gIDEgZmlsZSBjaGFuZ2VkLCAyIGluc2VydGlvbnMo KyksIDEgZGVsZXRpb24oLSkKPiA+Cj4gPiBkaWZmIC0tZ2l0IGEvZHJpdmVycy9jcHVmcmVxL2Nw dWZyZXEuYyBiL2RyaXZlcnMvY3B1ZnJlcS9jcHVmcmVxLmMKPiA+IGluZGV4IDhjNGY5YzJmOWM0 NC4uMTA5NTU5NDM4ZjQ1IDEwMDY0NAo+ID4gLS0tIGEvZHJpdmVycy9jcHVmcmVxL2NwdWZyZXEu Ywo+ID4gKysrIGIvZHJpdmVycy9jcHVmcmVxL2NwdWZyZXEuYwo+ID4gQEAgLTE3NTYsNyArMTc1 Niw4IEBAIHN0YXRpYyB1bnNpZ25lZCBpbnQgY3B1ZnJlcV92ZXJpZnlfY3VycmVudF9mcmVxKHN0 cnVjdCBjcHVmcmVxX3BvbGljeSAqcG9saWN5LCBiCj4gPiAgewo+ID4gICAgICAgICB1bnNpZ25l ZCBpbnQgbmV3X2ZyZXE7Cj4gPgo+ID4gLSAgICAgICBuZXdfZnJlcSA9IGNwdWZyZXFfZHJpdmVy LT5nZXQocG9saWN5LT5jcHUpOwo+ID4gKyAgICAgICBuZXdfZnJlcSA9IGFyY2hfZnJlcV9nZXRf b25fY3B1KHBvbGljeS0+Y3B1KTsKPiA+ICsgICAgICAgbmV3X2ZyZXEgPSBuZXdfZnJlcSA/OiBj cHVmcmVxX2RyaXZlci0+Z2V0KHBvbGljeS0+Y3B1KTsKPiAKPiBQbGVhc2UgZG9uJ3QgdXNlID86 IGluIGdlbmVyYWwgYW5kIGl0IGlzIG5vdCBldmVuIHVzZWZ1bCBoZXJlIEFGQUlDUy4KPiAKPiBX aGF0IHdvdWxkIGJlIHdyb25nIHdpdGgKPiAKPiBuZXdfZnJlcSA9IGFyY2hfZnJlcV9nZXRfb25f Y3B1KHBvbGljeS0+Y3B1KTsKPiBpZiAoIW5ld19mcmVxKQo+ICAgICAgICAgbmV3X2ZyZXEgPSBj cHVmcmVxX2RyaXZlci0+Z2V0KHBvbGljeS0+Y3B1KTsKPiAKPiA/Ck5vdGhpbmcgd3Jvbmcgd2l0 aCB0aGF0LgoKLS0tClsxXSBodHRwczovL2xvcmUua2VybmVsLm9yZy9hbGwvWldYeTBoJTJGZkZm UWgrUmh5QGFybS5jb20vClsyXSBodHRwczovL2xvcmUua2VybmVsLm9yZy9sa21sLzZhNTcxMGY2 LWJmYmItNWRmZC0xMWNkLTBjZDAyMjIwY2VlN0BudmlkaWEuY29tLwotLS0KQlIKQmVhdGEKPiAK PiA+ICAgICAgICAgaWYgKCFuZXdfZnJlcSkKPiA+ICAgICAgICAgICAgICAgICByZXR1cm4gMDsK PiA+Cj4gPiAtLQoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X18KbGludXgtYXJtLWtlcm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5p bmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8v bGludXgtYXJtLWtlcm5lbAo=