From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ECA207C for ; Thu, 22 Sep 2022 17:01:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1663866112; x=1695402112; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to; bh=qCYHm4gaDtc3s29RTgpAEXNzALg1JlVgHM8D+GW9n+4=; b=OYT/4jfTU1PcYnE+YsoYBA7yXZsqDnEjOtPxIJeELOPCijpaZ0z5uKgH ROKOcviIpU0IEx7fvKR+svp+ggq/LL3JDZo7ATdxCxOIwqMYTL1L4GUUA RFPTXmlRScoDHdbLPvtU4uR6S5hbY5sk8l2QXgq2134/cdQ60eR87RBJy JdCOeP2LVVpunh0qzqKBA/umdrDwwu7kuLMOnWK3W/71J4y8V9Vs4R8Da DgGkXuyUXdCpIx05UZqpO8uuO2TJQzPVGIVsvMuilrk8vaiHfmQ4dja0d u8q7hVB5Wg0r8g2TpF6raA9vS6xz2g3SCIiFAXJi4HY5cWKHgIZWglIS1 Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10478"; a="386649015" X-IronPort-AV: E=Sophos;i="5.93,337,1654585200"; d="scan'208,223";a="386649015" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2022 10:01:48 -0700 X-IronPort-AV: E=Sophos;i="5.93,337,1654585200"; d="scan'208,223";a="948675428" Received: from sponnura-mobl1.amr.corp.intel.com (HELO [10.209.58.200]) ([10.209.58.200]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2022 10:01:46 -0700 Content-Type: multipart/mixed; boundary="------------3lBZGQfj2C8pWp3quwOFRdc1" Message-ID: <88c17568-8694-940a-0f1f-9d345e8dcbdb@intel.com> Date: Thu, 22 Sep 2022 10:01:46 -0700 Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH] ACPI: processor_idle: Skip dummy wait for processors based on the Zen microarchitecture Content-Language: en-US To: K Prateek Nayak , linux-kernel@vger.kernel.org Cc: rafael@kernel.org, lenb@kernel.org, linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org, dave.hansen@linux.intel.com, bp@alien8.de, tglx@linutronix.de, andi@lisas.de, puwen@hygon.cn, mario.limonciello@amd.com, peterz@infradead.org, rui.zhang@intel.com, gpiccoli@igalia.com, daniel.lezcano@linaro.org, ananth.narayan@amd.com, gautham.shenoy@amd.com, Calvin Ong , stable@vger.kernel.org, regressions@lists.linux.dev References: <20220921063638.2489-1-kprateek.nayak@amd.com> <20e78a49-25df-c83d-842e-1d624655cfd7@intel.com> <0885eecb-042f-3b74-2965-7d657de59953@amd.com> From: Dave Hansen In-Reply-To: <0885eecb-042f-3b74-2965-7d657de59953@amd.com> This is a multi-part message in MIME format. --------------3lBZGQfj2C8pWp3quwOFRdc1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/22/22 09:54, K Prateek Nayak wrote: > > On 9/22/2022 10:14 PM, Dave Hansen wrote: >> On 9/20/22 23:36, K Prateek Nayak wrote: >>> Cc: stable@vger.kernel.org >>> Cc: regressions@lists.linux.dev >> *Is* this a regression? > On second thought, it is not a regression. > Will remove the tag on v2. What were you planning for v2? Rafael suggested something like the attached patch. It's not nearly as fragile as the Zen check you proposed earlier. Any testing or corrections on the commentary would be appreciated. --------------3lBZGQfj2C8pWp3quwOFRdc1 Content-Type: text/x-patch; charset=UTF-8; name="0001-ACPI-processor-idle-Limit-Dummy-wait-workaround-to-o.patch" Content-Disposition: attachment; filename*0="0001-ACPI-processor-idle-Limit-Dummy-wait-workaround-to-o.pa"; filename*1="tch" Content-Transfer-Encoding: base64 RnJvbSA1NGU0NjY4MTIyZDQ0N2VlODBlYzQ2NWYyNDRiMTlkOTY4YzRhN2M2IE1vbiBTZXAg MTcgMDA6MDA6MDAgMjAwMQpGcm9tOiBEYXZlIEhhbnNlbiA8ZGF2ZS5oYW5zZW5AaW50ZWwu Y29tPgpEYXRlOiBUaHUsIDIyIFNlcCAyMDIyIDA5OjIyOjI2IC0wNzAwClN1YmplY3Q6IFtQ QVRDSF0gQUNQSTogcHJvY2Vzc29yIGlkbGU6IExpbWl0ICJEdW1teSB3YWl0IiB3b3JrYXJv dW5kIHRvIG9sZAogSW50ZWwgc3lzdGVtcwoKT2xkLCBjaXJjYSAyMDAyIGNoaXBzZXRzIGhh dmUgYSBidWc6IHRoZXkgZG9uJ3QgZ28gaWRsZSB3aGVuIHRoZXkgYXJlCnN1cHBvc2VkIHRv LiAgU28sIGEgd29ya2Fyb3VuZCB3YXMgYWRkZWQgdG8gc2xvdyB0aGUgQ1BVIGRvd24gYW5k CmVuc3VyZSB0aGF0IHRoZSBDUFUgd2FpdHMgYSBiaXQgZm9yIHRoZSBjaGlwc2V0IHRvIGFj dHVhbGx5IGdvIGlkbGUuClRoaXMgd29ya2Fyb3VuZCBpcyBhbmNpZW50IGFuZCBoYXMgYmVl biBpbiBwbGFjZSBpbiBzb21lIGZvcm0gc2luY2UKdGhlIG9yaWdpbmFsIGtlcm5lbCBBQ1BJ IGltcGxlbWVudGF0aW9uLgoKQnV0LCB0aGlzIHdvcmthcm91bmQgaXMgdmVyeSBwYWluZnVs IG9uIG1vZGVybiBzeXN0ZW1zLiAgVGhlICJpbmIoKSIKY2FuIHRha2UgdGhvdXNhbmRzIG9m IGN5Y2xlcyAoc2VlIExpbms6IGZvciBzb21lIG1vcmUgZGV0YWlsZWQKYXJjaGFlb2xvZ3kp LgoKRmlyc3QgYW5kIGZvcmVtb3N0LCBtb2Rlcm4gc3lzdGVtcyBzaG91bGQgbm90IGJlIHVz aW5nIHRoaXMgY29kZS4KVHlwaWNhbCBJbnRlbCBzeXN0ZW1zIGhhdmUgbm90IHVzZWQgaXQg aW4gb3ZlciBhIGRlY2FkZSBiZWNhdXNlIGl0CmlzIGhvcnJpYmx5IGluZmVyaW9yIHRvIE1X QUlULWJhc2VkIGlkbGUuCgpEZXNwaXRlIHRoaXMsIHBlb3BsZSBkbyBzZWVtIHRvIGJlIHRy aXBwaW5nIG92ZXIgdGhpcyB3b3JrYXJvdW5kIG9uCkFNRCBDUFVzIHRvZGF5LgoKTGltaXQg dGhlICJkdW1teSB3YWl0IiB3b3JrYXJvdW5kIHRvIEludGVsIHN5c3RlbXMuICBTaW5jZSB0 aGlzCmNvZGUgaXMgb25seSB1c2VkIG9uIGFuY2llbnQgSW50ZWwgc3lzdGVtcywgdGhpcyBm aXggc2hvdWxkIHJlbmRlciBpdApoYXJtbGVzcyBldmVyeXdoZXJlIGVsc2UsIGluY2x1ZGlu ZyB0aGUgbW9kZXJuIEFNRCBvbmVzLgoKU2lnbmVkLW9mZi1ieTogRGF2ZSBIYW5zZW4gPGRh dmUuaGFuc2VuQGxpbnV4LmludGVsLmNvbT4KQ2M6IExlbiBCcm93biA8bGVuYkBrZXJuZWwu b3JnPgpTdWdnZXN0ZWQtYnk6IFJhZmFlbCBKLiBXeXNvY2tpIDxyYWZhZWwuai53eXNvY2tp QGludGVsLmNvbT4KUmVwb3J0ZWQtYnk6IEsgUHJhdGVlayBOYXlhayA8a3ByYXRlZWsubmF5 YWtAYW1kLmNvbT4KTGluazogaHR0cHM6Ly9sb3JlLmtlcm5lbC5vcmcvYWxsLzIwMjIwOTIx MDYzNjM4LjI0ODktMS1rcHJhdGVlay5uYXlha0BhbWQuY29tLwotLS0KIGRyaXZlcnMvYWNw aS9wcm9jZXNzb3JfaWRsZS5jIHwgMjMgKysrKysrKysrKysrKysrKysrKystLS0KIDEgZmls ZSBjaGFuZ2VkLCAyMCBpbnNlcnRpb25zKCspLCAzIGRlbGV0aW9ucygtKQoKZGlmZiAtLWdp dCBhL2RyaXZlcnMvYWNwaS9wcm9jZXNzb3JfaWRsZS5jIGIvZHJpdmVycy9hY3BpL3Byb2Nl c3Nvcl9pZGxlLmMKaW5kZXggMTZhMTY2M2QwMmQ0Li45ZjQwOTE3YzQ5ZWYgMTAwNjQ0Ci0t LSBhL2RyaXZlcnMvYWNwaS9wcm9jZXNzb3JfaWRsZS5jCisrKyBiL2RyaXZlcnMvYWNwaS9w cm9jZXNzb3JfaWRsZS5jCkBAIC01MzEsMTAgKzUzMSwyNyBAQCBzdGF0aWMgdm9pZCB3YWl0 X2Zvcl9mcmVlemUodm9pZCkKIAkvKiBObyBkZWxheSBpcyBuZWVkZWQgaWYgd2UgYXJlIGlu IGd1ZXN0ICovCiAJaWYgKGJvb3RfY3B1X2hhcyhYODZfRkVBVFVSRV9IWVBFUlZJU09SKSkK IAkJcmV0dXJuOworCS8qCisJICogTW9kZXJuICg+PU5laGFsZW0pIEludGVsIHN5c3RlbXMg dXNlIEFDUEkgdmlhIGludGVsX2lkbGUsCisJICogbm90IHRoaXMgY29kZS4gIEFzc3VtZSB0 aGF0IGFueSBJbnRlbCBzeXN0ZW1zIHVzaW5nIHRoaXMKKwkgKiBhcmUgYW5jaWVudCBhbmQg bWF5IG5lZWQgdGhlIGR1bW15IHdhaXQuICBUaGlzIGFsc28gYXNzdW1lcworCSAqIHRoYXQg dGhlIG1vdGl2YXRpbmcgY2hpcHNldCBpc3N1ZSB3YXMgSW50ZWwtb25seS4KKwkgKi8KKwlp ZiAoYm9vdF9jcHVfZGF0YS54ODZfdmVuZG9yICE9IFg4Nl9WRU5ET1JfSU5URUwpCisJCXJl dHVybjsKICNlbmRpZgotCS8qIER1bW15IHdhaXQgb3AgLSBtdXN0IGRvIHNvbWV0aGluZyB1 c2VsZXNzIGFmdGVyIFBfTFZMMiByZWFkCi0JICAgYmVjYXVzZSBjaGlwc2V0cyBjYW5ub3Qg Z3VhcmFudGVlIHRoYXQgU1RQQ0xLIyBzaWduYWwKLQkgICBnZXRzIGFzc2VydGVkIGluIHRp bWUgdG8gZnJlZXplIGV4ZWN1dGlvbiBwcm9wZXJseS4gKi8KKwkvKgorCSAqIER1bW15IHdh aXQgb3AgLSBtdXN0IGRvIHNvbWV0aGluZyB1c2VsZXNzIGFmdGVyIFBfTFZMMiByZWFkCisJ ICogYmVjYXVzZSBjaGlwc2V0cyBjYW5ub3QgZ3VhcmFudGVlIHRoYXQgU1RQQ0xLIyBzaWdu YWwgZ2V0cworCSAqIGFzc2VydGVkIGluIHRpbWUgdG8gZnJlZXplIGV4ZWN1dGlvbiBwcm9w ZXJseQorCSAqCisJICogVGhpcyB3b3JrYXJvdW5kIGhhcyBiZWVuIGluIHBsYWNlIHNpbmNl IHRoZSBvcmlnaW5hbCBBQ1BJCisJICogaW1wbGVtZW50YXRpb24gd2FzIG1lcmdlZCwgY2ly Y2EgMjAwMi4KKwkgKgorCSAqIElmIGEgcHJvZmlsZSBpcyBwb2ludGluZyB0byB0aGlzIGlu c3RydWN0aW9uLCBwbGVhc2UgZmlyc3QKKwkgKiBjb25zaWRlciBtb3ZpbmcgeW91ciBzeXN0 ZW0gdG8gYSBtb3JlIG1vZGVybiBpZGxlCisJICogbWVjaGFuaXNtLgorCSAqLwogCWlubChh Y3BpX2dibF9GQURULnhwbV90aW1lcl9ibG9jay5hZGRyZXNzKTsKIH0KIAotLSAKMi4yNS4x Cgo= --------------3lBZGQfj2C8pWp3quwOFRdc1--