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 0918577A0E; Tue, 12 Mar 2024 08:45:37 +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=1710233139; cv=none; b=UD/dMQTAjEikFviFALDA1o78TYK+Izhn981Vf49vH55R+XBVFhZKf+JriZNkzNPNfhOVCA3L/4xoYkEQf6UATgdF5648NpEN4sZRJgXxr42hNVx5b3sYiLaRaYnV1sxvMoIgyUul56du5gIL3UXHn0tgXuLDgs6eBnUVmnsYIH4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710233139; c=relaxed/simple; bh=sh38yJG3tCaBIyKt3Moq30fT1P7GQyX2mpE8GaX4Wzo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ntfx0MeqHSgr3tJt7BbEk2mVbXFWFBHv0w0Qap38YW0rPybeCCp6Kp/msP/FjRI6aYz2IoW3gMk+YcgUe+vXVUhRv/qUMHS9nnKlDBbTnXhd1dclt7wd4MDgcNeWKG8DXbOJuatfvY9a1TySW5BPYfAVNPyauGhr1rfOl6Pxkc8= 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 772891007; Tue, 12 Mar 2024 01:46:14 -0700 (PDT) Received: from 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 BC9F73F73F; Tue, 12 Mar 2024 01:45:33 -0700 (PDT) Date: Tue, 12 Mar 2024 09:44:52 +0100 From: Beata Michalska To: Vanshidhar Konda Cc: "lihuisong (C)" , Ionela Voinescu , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, rafael@kernel.org, sumitg@nvidia.com, zengheng4@huawei.com, yang@os.amperecomputing.com, will@kernel.org, sudeep.holla@arm.com, liuyonglong@huawei.com, zhanjie9@hisilicon.com, linux-acpi@vger.kernel.org Subject: Re: Re: [PATCH v1 2/3] arm64: idle: Cache AMU counters before entering idle Message-ID: References: <20240229162520.970986-1-vanshikonda@os.amperecomputing.com> <20240229162520.970986-3-vanshikonda@os.amperecomputing.com> <3ed907bf-9526-3a46-41b9-8a0c747122f1@huawei.com> 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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Mon, Mar 11, 2024 at 11:27:27AM -0700, Vanshidhar Konda wrote: > On Thu, Mar 07, 2024 at 11:17:26AM +0800, lihuisong (C) wrote: > > > > 在 2024/3/1 0:25, Vanshidhar Konda 写道: > > > AMU counters do not increment while a CPU is in idle. Saving the value > > > of the core and constant counters prior to invoking WFI allows FIE to > > > compute the frequency of a CPU that is idle. > > > > > > Signed-off-by: Vanshidhar Konda > > > --- > > > arch/arm64/kernel/idle.c | 10 ++++++++++ > > > arch/arm64/kernel/topology.c | 14 ++++++++------ > > > 2 files changed, 18 insertions(+), 6 deletions(-) > > > > > > diff --git a/arch/arm64/kernel/idle.c b/arch/arm64/kernel/idle.c > > > index 05cfb347ec26..5ed2e57188a8 100644 > > > --- a/arch/arm64/kernel/idle.c > > > +++ b/arch/arm64/kernel/idle.c > > > @@ -26,6 +26,16 @@ void __cpuidle cpu_do_idle(void) > > > arm_cpuidle_save_irq_context(&context); > > > +#ifdef CONFIG_ARM64_AMU_EXTN > > > + /* Update the AMU counters before entering WFI. The cached AMU counter > > > + * value is used to determine CPU frequency while the CPU is idle > > > + * without needing to wake up the CPU. > > > + */ > > > + > > > + if (cpu_has_amu_feat(smp_processor_id())) > > > + update_freq_counters_refs(); > > > +#endif > > The below point I has mentioned in [1]. > > This is just for the WFI state. > > What about other deeper idle states, like retention and power down? > > The path to enter idle state is different for them. We should do this > > for all idle states. > > > > Yes. That makes sense. I'll account for them in the next version of the > patch. I'll work on the next version of the patch based on the updated > patch from @Beata. > This should now be covered by [1] --- [1]https://lore.kernel.org/all/20240312083431.3239989-4-beata.michalska@arm.com/ --- BR Beata > Thanks, > Vanshi > > > > + > > > dsb(sy); > > > wfi(); > > > diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c > > > index db8d14525cf4..8905eb0c681f 100644 > > > --- a/arch/arm64/kernel/topology.c > > > +++ b/arch/arm64/kernel/topology.c > > > @@ -240,13 +240,15 @@ unsigned int arch_freq_get_on_cpu(int cpu) > > > } while (read_seqcount_retry(&cpu_sample->seq, seq)); > > > /* > > > - * Bail on invalid count and when the last update was too long ago, > > > - * which covers idle and NOHZ full CPUs. > > > + * Bail on invalid count and when the last update was too long ago. > > > + * This covers idle, NOHZ full and isolated CPUs. > > > + * > > > + * Idle CPUs don't need to be measured because AMU counters stop > > > + * incrementing during WFI/WFE. > > > */ > > > - if (!delta_const_cnt || ((jiffies - last) > MAX_SAMPLE_AGE)) { > > > - if (!(housekeeping_cpu(cpu, HK_TYPE_TICK) && idle_cpu(cpu))) > > > - goto fallback; > > > - } > > > + if (!delta_const_cnt || > > > + ((jiffies - last) > MAX_SAMPLE_AGE && !idle_cpu(cpu))) > > > + goto fallback; > > > /* > > > * CPU frequency = reference perf (in Hz) * (/\ delivered) / (/\ reference) > > [1] https://lore.kernel.org/linux-arm-kernel/20231212072617.14756-1-lihuisong@huawei.com/ > > 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 970FAC54E58 for ; Tue, 12 Mar 2024 08:45:54 +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; 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Tue, 12 Mar 2024 01:45:33 -0700 (PDT) Date: Tue, 12 Mar 2024 09:44:52 +0100 From: Beata Michalska To: Vanshidhar Konda Cc: "lihuisong (C)" , Ionela Voinescu , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, rafael@kernel.org, sumitg@nvidia.com, zengheng4@huawei.com, yang@os.amperecomputing.com, will@kernel.org, sudeep.holla@arm.com, liuyonglong@huawei.com, zhanjie9@hisilicon.com, linux-acpi@vger.kernel.org Subject: Re: Re: [PATCH v1 2/3] arm64: idle: Cache AMU counters before entering idle Message-ID: References: <20240229162520.970986-1-vanshikonda@os.amperecomputing.com> <20240229162520.970986-3-vanshikonda@os.amperecomputing.com> <3ed907bf-9526-3a46-41b9-8a0c747122f1@huawei.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-20240312_014540_007855_FC853228 X-CRM114-Status: GOOD ( 30.21 ) 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 T24gTW9uLCBNYXIgMTEsIDIwMjQgYXQgMTE6Mjc6MjdBTSAtMDcwMCwgVmFuc2hpZGhhciBLb25k YSB3cm90ZToKPiBPbiBUaHUsIE1hciAwNywgMjAyNCBhdCAxMToxNzoyNkFNICswODAwLCBsaWh1 aXNvbmcgKEMpIHdyb3RlOgo+ID4gCj4gPiDlnKggMjAyNC8zLzEgMDoyNSwgVmFuc2hpZGhhciBL b25kYSDlhpnpgZM6Cj4gPiA+IEFNVSBjb3VudGVycyBkbyBub3QgaW5jcmVtZW50IHdoaWxlIGEg Q1BVIGlzIGluIGlkbGUuIFNhdmluZyB0aGUgdmFsdWUKPiA+ID4gb2YgdGhlIGNvcmUgYW5kIGNv bnN0YW50IGNvdW50ZXJzIHByaW9yIHRvIGludm9raW5nIFdGSSBhbGxvd3MgRklFIHRvCj4gPiA+ IGNvbXB1dGUgdGhlIGZyZXF1ZW5jeSBvZiBhIENQVSB0aGF0IGlzIGlkbGUuCj4gPiA+IAo+ID4g PiBTaWduZWQtb2ZmLWJ5OiBWYW5zaGlkaGFyIEtvbmRhIDx2YW5zaGlrb25kYUBvcy5hbXBlcmVj b21wdXRpbmcuY29tPgo+ID4gPiAtLS0KPiA+ID4gIGFyY2gvYXJtNjQva2VybmVsL2lkbGUuYyAg ICAgfCAxMCArKysrKysrKysrCj4gPiA+ICBhcmNoL2FybTY0L2tlcm5lbC90b3BvbG9neS5jIHwg MTQgKysrKysrKystLS0tLS0KPiA+ID4gIDIgZmlsZXMgY2hhbmdlZCwgMTggaW5zZXJ0aW9ucygr KSwgNiBkZWxldGlvbnMoLSkKPiA+ID4gCj4gPiA+IGRpZmYgLS1naXQgYS9hcmNoL2FybTY0L2tl cm5lbC9pZGxlLmMgYi9hcmNoL2FybTY0L2tlcm5lbC9pZGxlLmMKPiA+ID4gaW5kZXggMDVjZmIz NDdlYzI2Li41ZWQyZTU3MTg4YTggMTAwNjQ0Cj4gPiA+IC0tLSBhL2FyY2gvYXJtNjQva2VybmVs L2lkbGUuYwo+ID4gPiArKysgYi9hcmNoL2FybTY0L2tlcm5lbC9pZGxlLmMKPiA+ID4gQEAgLTI2 LDYgKzI2LDE2IEBAIHZvaWQgX19jcHVpZGxlIGNwdV9kb19pZGxlKHZvaWQpCj4gPiA+ICAJYXJt X2NwdWlkbGVfc2F2ZV9pcnFfY29udGV4dCgmY29udGV4dCk7Cj4gPiA+ICsjaWZkZWYgQ09ORklH X0FSTTY0X0FNVV9FWFROCj4gPiA+ICsJLyogVXBkYXRlIHRoZSBBTVUgY291bnRlcnMgYmVmb3Jl IGVudGVyaW5nIFdGSS4gVGhlIGNhY2hlZCBBTVUgY291bnRlcgo+ID4gPiArCSAqIHZhbHVlIGlz IHVzZWQgdG8gZGV0ZXJtaW5lIENQVSBmcmVxdWVuY3kgd2hpbGUgdGhlIENQVSBpcyBpZGxlCj4g PiA+ICsJICogd2l0aG91dCBuZWVkaW5nIHRvIHdha2UgdXAgdGhlIENQVS4KPiA+ID4gKwkgKi8K PiA+ID4gKwo+ID4gPiArCWlmIChjcHVfaGFzX2FtdV9mZWF0KHNtcF9wcm9jZXNzb3JfaWQoKSkp Cj4gPiA+ICsJCXVwZGF0ZV9mcmVxX2NvdW50ZXJzX3JlZnMoKTsKPiA+ID4gKyNlbmRpZgo+ID4g VGhlIGJlbG93IHBvaW50IEkgaGFzIG1lbnRpb25lZCBpbiBbMV0uCj4gPiBUaGlzIGlzIGp1c3Qg Zm9yIHRoZSBXRkkgc3RhdGUuCj4gPiBXaGF0IGFib3V0IG90aGVyIGRlZXBlciBpZGxlIHN0YXRl cywgbGlrZSByZXRlbnRpb24gYW5kIHBvd2VyIGRvd24/Cj4gPiBUaGUgcGF0aCB0byBlbnRlciBp ZGxlIHN0YXRlIGlzIGRpZmZlcmVudCBmb3IgdGhlbS4gV2Ugc2hvdWxkIGRvIHRoaXMKPiA+IGZv ciBhbGwgaWRsZSBzdGF0ZXMuCj4gPiAKPiAKPiBZZXMuIFRoYXQgbWFrZXMgc2Vuc2UuIEknbGwg YWNjb3VudCBmb3IgdGhlbSBpbiB0aGUgbmV4dCB2ZXJzaW9uIG9mIHRoZQo+IHBhdGNoLiBJJ2xs IHdvcmsgb24gdGhlIG5leHQgdmVyc2lvbiBvZiB0aGUgcGF0Y2ggYmFzZWQgb24gdGhlIHVwZGF0 ZWQKPiBwYXRjaCBmcm9tIEBCZWF0YS4KPiAKVGhpcyBzaG91bGQgbm93IGJlIGNvdmVyZWQgYnkg WzFdCgotLS0KWzFdaHR0cHM6Ly9sb3JlLmtlcm5lbC5vcmcvYWxsLzIwMjQwMzEyMDgzNDMxLjMy Mzk5ODktNC1iZWF0YS5taWNoYWxza2FAYXJtLmNvbS8KCi0tLQpCUgpCZWF0YQoKPiBUaGFua3Ms Cj4gVmFuc2hpCj4gCj4gPiA+ICsKPiA+ID4gIAlkc2Ioc3kpOwo+ID4gPiAgCXdmaSgpOwo+ID4g PiBkaWZmIC0tZ2l0IGEvYXJjaC9hcm02NC9rZXJuZWwvdG9wb2xvZ3kuYyBiL2FyY2gvYXJtNjQv a2VybmVsL3RvcG9sb2d5LmMKPiA+ID4gaW5kZXggZGI4ZDE0NTI1Y2Y0Li44OTA1ZWIwYzY4MWYg MTAwNjQ0Cj4gPiA+IC0tLSBhL2FyY2gvYXJtNjQva2VybmVsL3RvcG9sb2d5LmMKPiA+ID4gKysr IGIvYXJjaC9hcm02NC9rZXJuZWwvdG9wb2xvZ3kuYwo+ID4gPiBAQCAtMjQwLDEzICsyNDAsMTUg QEAgdW5zaWduZWQgaW50IGFyY2hfZnJlcV9nZXRfb25fY3B1KGludCBjcHUpCj4gPiA+ICAJfSB3 aGlsZSAocmVhZF9zZXFjb3VudF9yZXRyeSgmY3B1X3NhbXBsZS0+c2VxLCBzZXEpKTsKPiA+ID4g IAkvKgo+ID4gPiAtCSAqIEJhaWwgb24gaW52YWxpZCBjb3VudCBhbmQgd2hlbiB0aGUgbGFzdCB1 cGRhdGUgd2FzIHRvbyBsb25nIGFnbywKPiA+ID4gLQkgKiB3aGljaCBjb3ZlcnMgaWRsZSBhbmQg Tk9IWiBmdWxsIENQVXMuCj4gPiA+ICsJICogQmFpbCBvbiBpbnZhbGlkIGNvdW50IGFuZCB3aGVu IHRoZSBsYXN0IHVwZGF0ZSB3YXMgdG9vIGxvbmcgYWdvLgo+ID4gPiArCSAqIFRoaXMgY292ZXJz IGlkbGUsIE5PSFogZnVsbCBhbmQgaXNvbGF0ZWQgQ1BVcy4KPiA+ID4gKwkgKgo+ID4gPiArCSAq IElkbGUgQ1BVcyBkb24ndCBuZWVkIHRvIGJlIG1lYXN1cmVkIGJlY2F1c2UgQU1VIGNvdW50ZXJz IHN0b3AKPiA+ID4gKwkgKiBpbmNyZW1lbnRpbmcgZHVyaW5nIFdGSS9XRkUuCj4gPiA+ICAJICov Cj4gPiA+IC0JaWYgKCFkZWx0YV9jb25zdF9jbnQgfHwgKChqaWZmaWVzIC0gbGFzdCkgPiBNQVhf U0FNUExFX0FHRSkpIHsKPiA+ID4gLQkJaWYgKCEoaG91c2VrZWVwaW5nX2NwdShjcHUsIEhLX1RZ UEVfVElDSykgJiYgaWRsZV9jcHUoY3B1KSkpCj4gPiA+IC0JCQlnb3RvIGZhbGxiYWNrOwo+ID4g PiAtCX0KPiA+ID4gKwlpZiAoIWRlbHRhX2NvbnN0X2NudCB8fAo+ID4gPiArCSAgICAoKGppZmZp ZXMgLSBsYXN0KSA+IE1BWF9TQU1QTEVfQUdFICYmICFpZGxlX2NwdShjcHUpKSkKPiA+ID4gKwkJ Z290byBmYWxsYmFjazsKPiA+ID4gIAkvKgo+ID4gPiAgCSAqIENQVSBmcmVxdWVuY3kgPSByZWZl cmVuY2UgcGVyZiAoaW4gSHopICogKC9cIGRlbGl2ZXJlZCkgLyAoL1wgcmVmZXJlbmNlKQo+ID4g WzFdIGh0dHBzOi8vbG9yZS5rZXJuZWwub3JnL2xpbnV4LWFybS1rZXJuZWwvMjAyMzEyMTIwNzI2 MTcuMTQ3NTYtMS1saWh1aXNvbmdAaHVhd2VpLmNvbS8KPiA+IAoKX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX18KbGludXgtYXJtLWtlcm5lbCBtYWlsaW5nIGxp c3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZy YWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtYXJtLWtlcm5lbAo=