From patchwork Fri Oct 13 02:57:37 2023
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: "Meng, Li (Jassmine)"
X-Patchwork-Id: 13420049
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 vger.kernel.org (vger.kernel.org [23.128.96.18])
by smtp.lore.kernel.org (Postfix) with ESMTP id B8BB7CDB482
for ; Fri, 13 Oct 2023 02:58:32 +0000 (UTC)
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
id S229568AbjJMC6c (ORCPT );
Thu, 12 Oct 2023 22:58:32 -0400
Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35468 "EHLO
lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
with ESMTP id S229521AbjJMC60 (ORCPT
); Thu, 12 Oct 2023 22:58:26 -0400
Received: from NAM10-BN7-obe.outbound.protection.outlook.com
(mail-bn7nam10on2056.outbound.protection.outlook.com [40.107.92.56])
by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1167A9;
Thu, 12 Oct 2023 19:58:22 -0700 (PDT)
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none;
b=ejMLXYLvIlG6hKs7gMI65d11n7g8UDv5F0oolt0zl2SnJapuhGxWRJ/RYNzxe3xUCkzZ9QhCrTpg1/+MED3mCPa7JvPIB5y3t/N/tMGzlYE+ISbOtWvaSwZ2NsGz92+4J3cqvsgazKO0so3CAJz/DESoLXmHAcH1v1N6tXyFl9nGP1SeQErrU60O1mMzO3qSpTb8LtYSluMqc6q80zLNPiIIrEd4owwxD5nEcpA1BBZMNMz+RKM+hWrRNSchszPIHbUfYqd63PBLSeo4kpHPhP3KbMU2LLk/ezywdn3yQW0Kss6jxTVhTwuDPALdv0XLmdBFFrw4hw8TGyCi0/zzEg==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com;
s=arcselector9901;
h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1;
bh=mpqCLwo80Q+CSCXFfWuoADKctj8OoSbA2jq+gzqAQZM=;
b=G+N5g5Yz8zUlL4aatumTO4aT8vQgbRgna6mtOSEr6n4JIevTrHLaCnX1HCNCaCa4d7ZFqfwbpgyVNPp+LCUm4HXZmfatBWEl4PskZ0q20qMxG+CyWb8qQ0bYACRoV3epRWbiOWbvhhKy/O3Nvv1ieDwJbD6R7D0PddlHvFN4qmCIe0Va5SUOnQrkyU0ouWmJYwlgGGyHhW65PeCzY/M8vQucvQYTJ4Y1C5RIvmzR0Dm7Ijnl1d+AxvvjZx7m46LkBfVnDeN9OwsEB0bcOnre+MAbz+3XgKbem9le4qE7purEuA85cmcp6vPxWjuKQUJPB2DsWeYao3txV9qcPgvENg==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is
165.204.84.17) smtp.rcpttodomain=intel.com smtp.mailfrom=amd.com; dmarc=pass
(p=quarantine sp=quarantine pct=100) action=none header.from=amd.com;
dkim=none (message not signed); arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1;
h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;
bh=mpqCLwo80Q+CSCXFfWuoADKctj8OoSbA2jq+gzqAQZM=;
b=OSIvkKfFKsCMCXapvApPYpJX4PZ7/DXvSE3bAFztXP/mlTCw1Za25TsvNDhO5/hT5maGE7D/lsaP56fIXyr15dD+U3C773+on1IoHLYTz4WCGUJBCEhcLAdm20dp6Lu37FEi1mI24dFlkLLADDEwXYPTJb0edhuV6UmxLuy5Igw=
Received: from MW4PR03CA0217.namprd03.prod.outlook.com (2603:10b6:303:b9::12)
by DM4PR12MB7645.namprd12.prod.outlook.com (2603:10b6:8:107::16) with
Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6863.36; Fri, 13 Oct
2023 02:58:17 +0000
Received: from CO1PEPF000044EF.namprd05.prod.outlook.com
(2603:10b6:303:b9:cafe::d3) by MW4PR03CA0217.outlook.office365.com
(2603:10b6:303:b9::12) with Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6863.44 via Frontend
Transport; Fri, 13 Oct 2023 02:58:17 +0000
X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17)
smtp.mailfrom=amd.com; dkim=none (message not signed)
header.d=none;dmarc=pass action=none header.from=amd.com;
Received-SPF: Pass (protection.outlook.com: domain of amd.com designates
165.204.84.17 as permitted sender) receiver=protection.outlook.com;
client-ip=165.204.84.17; helo=SATLEXMB04.amd.com; pr=C
Received: from SATLEXMB04.amd.com (165.204.84.17) by
CO1PEPF000044EF.mail.protection.outlook.com (10.167.241.69) with Microsoft
SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id
15.20.6838.22 via Frontend Transport; Fri, 13 Oct 2023 02:58:17 +0000
Received: from jasmine-meng.amd.com (10.180.168.240) by SATLEXMB04.amd.com
(10.181.40.145) with Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Thu, 12 Oct
2023 21:58:11 -0500
From: Meng Li
To: "Rafael J . Wysocki" ,
Huang Rui
CC: , ,
, ,
Shuah Khan ,
,
"Nathan Fontenot" ,
Deepak Sharma ,
Alex Deucher ,
Mario Limonciello ,
Shimmer Huang ,
"Perry Yuan" ,
Xiaojian Du ,
Viresh Kumar ,
Borislav Petkov ,
"Oleksandr Natalenko" ,
Meng Li , Wyes Karny
Subject: [PATCH V9 3/7] cpufreq: amd-pstate: Enable amd-pstate preferred core
supporting.
Date: Fri, 13 Oct 2023 10:57:37 +0800
Message-ID: <20231013025741.3332520-4-li.meng@amd.com>
X-Mailer: git-send-email 2.34.1
In-Reply-To: <20231013025741.3332520-1-li.meng@amd.com>
References: <20231013025741.3332520-1-li.meng@amd.com>
MIME-Version: 1.0
X-Originating-IP: [10.180.168.240]
X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com
(10.181.40.145)
X-EOPAttributedMessage: 0
X-MS-PublicTrafficType: Email
X-MS-TrafficTypeDiagnostic: CO1PEPF000044EF:EE_|DM4PR12MB7645:EE_
X-MS-Office365-Filtering-Correlation-Id: 96177df9-29f9-4615-dedb-08dbcb984039
X-MS-Exchange-SenderADCheck: 1
X-MS-Exchange-AntiSpam-Relay: 0
X-Microsoft-Antispam: BCL:0;
X-Microsoft-Antispam-Message-Info:
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
X-Forefront-Antispam-Report:
CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:SATLEXMB04.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230031)(4636009)(396003)(346002)(376002)(39860400002)(136003)(230922051799003)(82310400011)(186009)(1800799009)(451199024)(64100799003)(36840700001)(40470700004)(46966006)(16526019)(26005)(336012)(426003)(81166007)(1076003)(2616005)(8676002)(47076005)(7696005)(4326008)(8936002)(2906002)(7416002)(478600001)(30864003)(6666004)(70206006)(70586007)(41300700001)(5660300002)(316002)(54906003)(110136005)(6636002)(40460700003)(356005)(82740400003)(36756003)(86362001)(40480700001)(36860700001)(83380400001)(36900700001);DIR:OUT;SFP:1101;
X-OriginatorOrg: amd.com
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Oct 2023 02:58:17.4652
(UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id:
96177df9-29f9-4615-dedb-08dbcb984039
X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp:
TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com]
X-MS-Exchange-CrossTenant-AuthSource:
CO1PEPF000044EF.namprd05.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Anonymous
X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB7645
Precedence: bulk
List-ID:
X-Mailing-List: linux-pm@vger.kernel.org
amd-pstate driver utilizes the functions and data structures
provided by the ITMT architecture to enable the scheduler to
favor scheduling on cores which can be get a higher frequency
with lower voltage. We call it amd-pstate preferrred core.
Here sched_set_itmt_core_prio() is called to set priorities and
sched_set_itmt_support() is called to enable ITMT feature.
amd-pstate driver uses the highest performance value to indicate
the priority of CPU. The higher value has a higher priority.
The initial core rankings are set up by amd-pstate when the
system boots.
Add a variable hw_prefcore in cpudata structure. It will check
if the processor and power firmware support preferred core
feature.
Add one new early parameter `disable` to allow user to disable
the preferred core.
Only when hardware supports preferred core and user set `enabled`
in early parameter, amd pstate driver supports preferred core featue.
Tested-by: Oleksandr Natalenko
Reviewed-by: Huang Rui
Reviewed-by: Wyes Karny
Reviewed-by: Mario Limonciello
Co-developed-by: Perry Yuan
Signed-off-by: Perry Yuan
Signed-off-by: Meng Li
---
drivers/cpufreq/amd-pstate.c | 155 +++++++++++++++++++++++++++++++----
include/linux/amd-pstate.h | 4 +
2 files changed, 143 insertions(+), 16 deletions(-)
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 9a1e194d5cf8..58aa9ddff29e 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -37,6 +37,7 @@
#include
#include
#include
+#include
#include
#include
@@ -49,6 +50,8 @@
#define AMD_PSTATE_TRANSITION_LATENCY 20000
#define AMD_PSTATE_TRANSITION_DELAY 1000
+#define AMD_PSTATE_PREFCORE_THRESHOLD 166
+#define AMD_PSTATE_MAX_CPPC_PERF 255
/*
* TODO: We need more time to fine tune processors with shared memory solution
@@ -64,6 +67,7 @@ static struct cpufreq_driver amd_pstate_driver;
static struct cpufreq_driver amd_pstate_epp_driver;
static int cppc_state = AMD_PSTATE_UNDEFINED;
static bool cppc_enabled;
+static bool amd_pstate_prefcore = true;
/*
* AMD Energy Preference Performance (EPP)
@@ -290,23 +294,21 @@ static inline int amd_pstate_enable(bool enable)
static int pstate_init_perf(struct amd_cpudata *cpudata)
{
u64 cap1;
- u32 highest_perf;
int ret = rdmsrl_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1,
&cap1);
if (ret)
return ret;
- /*
- * TODO: Introduce AMD specific power feature.
- *
- * CPPC entry doesn't indicate the highest performance in some ASICs.
+ /* For platforms that do not support the preferred core feature, the
+ * highest_pef may be configured with 166 or 255, to avoid max frequency
+ * calculated wrongly. we take the AMD_CPPC_HIGHEST_PERF(cap1) value as
+ * the default max perf.
*/
- highest_perf = amd_get_highest_perf();
- if (highest_perf > AMD_CPPC_HIGHEST_PERF(cap1))
- highest_perf = AMD_CPPC_HIGHEST_PERF(cap1);
-
- WRITE_ONCE(cpudata->highest_perf, highest_perf);
+ if (cpudata->hw_prefcore)
+ WRITE_ONCE(cpudata->highest_perf, AMD_PSTATE_PREFCORE_THRESHOLD);
+ else
+ WRITE_ONCE(cpudata->highest_perf, AMD_CPPC_HIGHEST_PERF(cap1));
WRITE_ONCE(cpudata->nominal_perf, AMD_CPPC_NOMINAL_PERF(cap1));
WRITE_ONCE(cpudata->lowest_nonlinear_perf, AMD_CPPC_LOWNONLIN_PERF(cap1));
@@ -318,17 +320,15 @@ static int pstate_init_perf(struct amd_cpudata *cpudata)
static int cppc_init_perf(struct amd_cpudata *cpudata)
{
struct cppc_perf_caps cppc_perf;
- u32 highest_perf;
int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
if (ret)
return ret;
- highest_perf = amd_get_highest_perf();
- if (highest_perf > cppc_perf.highest_perf)
- highest_perf = cppc_perf.highest_perf;
-
- WRITE_ONCE(cpudata->highest_perf, highest_perf);
+ if (cpudata->hw_prefcore)
+ WRITE_ONCE(cpudata->highest_perf, AMD_PSTATE_PREFCORE_THRESHOLD);
+ else
+ WRITE_ONCE(cpudata->highest_perf, cppc_perf.highest_perf);
WRITE_ONCE(cpudata->nominal_perf, cppc_perf.nominal_perf);
WRITE_ONCE(cpudata->lowest_nonlinear_perf,
@@ -676,6 +676,93 @@ static void amd_perf_ctl_reset(unsigned int cpu)
wrmsrl_on_cpu(cpu, MSR_AMD_PERF_CTL, 0);
}
+/*
+ * Set amd-pstate preferred core enable can't be done directly from cpufreq callbacks
+ * due to locking, so queue the work for later.
+ */
+static void amd_pstste_sched_prefcore_workfn(struct work_struct *work)
+{
+ sched_set_itmt_support();
+}
+static DECLARE_WORK(sched_prefcore_work, amd_pstste_sched_prefcore_workfn);
+
+/*
+ * Get the highest performance register value.
+ * @cpu: CPU from which to get highest performance.
+ * @highest_perf: Return address.
+ *
+ * Return: 0 for success, -EIO otherwise.
+ */
+static int amd_pstate_get_highest_perf(int cpu, u32 *highest_perf)
+{
+ int ret;
+
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ u64 cap1;
+
+ ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1);
+ if (ret)
+ return ret;
+ WRITE_ONCE(*highest_perf, AMD_CPPC_HIGHEST_PERF(cap1));
+ } else {
+ u64 cppc_highest_perf;
+
+ ret = cppc_get_highest_perf(cpu, &cppc_highest_perf);
+ WRITE_ONCE(*highest_perf, cppc_highest_perf);
+ }
+
+ return (ret);
+}
+
+static void amd_pstate_init_prefcore(struct amd_cpudata *cpudata)
+{
+ int ret, prio;
+ u32 highest_perf;
+ static u32 max_highest_perf = 0, min_highest_perf = U32_MAX;
+
+ ret = amd_pstate_get_highest_perf(cpudata->cpu, &highest_perf);
+ if (ret)
+ return;
+
+ cpudata->hw_prefcore = true;
+ /* check if CPPC preferred core feature is enabled*/
+ if (highest_perf == AMD_PSTATE_MAX_CPPC_PERF) {
+ pr_debug("AMD CPPC preferred core is unsupported!\n");
+ cpudata->hw_prefcore = false;
+ return;
+ }
+
+ if (!amd_pstate_prefcore)
+ return;
+
+ /* The maximum value of highest perf is 255 */
+ prio = (int)(highest_perf & 0xff);
+ /*
+ * The priorities can be set regardless of whether or not
+ * sched_set_itmt_support(true) has been called and it is valid to
+ * update them at any time after it has been called.
+ */
+ sched_set_itmt_core_prio(highest_perf, cpudata->cpu);
+
+ if (max_highest_perf <= min_highest_perf) {
+ if (highest_perf > max_highest_perf)
+ max_highest_perf = highest_perf;
+
+ if (highest_perf < min_highest_perf)
+ min_highest_perf = highest_perf;
+
+ if (max_highest_perf > min_highest_perf) {
+ /*
+ * This code can be run during CPU online under the
+ * CPU hotplug locks, so sched_set_itmt_support()
+ * cannot be called from here. Queue up a work item
+ * to invoke it.
+ */
+ schedule_work(&sched_prefcore_work);
+ }
+ }
+}
+
static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
{
int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
@@ -697,6 +784,8 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
cpudata->cpu = policy->cpu;
+ amd_pstate_init_prefcore(cpudata);
+
ret = amd_pstate_init_perf(cpudata);
if (ret)
goto free_cpudata1;
@@ -845,6 +934,17 @@ static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy,
return sysfs_emit(buf, "%u\n", perf);
}
+static ssize_t show_amd_pstate_hw_prefcore(struct cpufreq_policy *policy,
+ char *buf)
+{
+ bool hw_prefcore;
+ struct amd_cpudata *cpudata = policy->driver_data;
+
+ hw_prefcore = READ_ONCE(cpudata->hw_prefcore);
+
+ return sysfs_emit(buf, "%s\n", hw_prefcore ? "supported" : "unsupported");
+}
+
static ssize_t show_energy_performance_available_preferences(
struct cpufreq_policy *policy, char *buf)
{
@@ -1037,18 +1137,27 @@ static ssize_t status_store(struct device *a, struct device_attribute *b,
return ret < 0 ? ret : count;
}
+static ssize_t prefcore_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%s\n", amd_pstate_prefcore ? "enabled" : "disabled");
+}
+
cpufreq_freq_attr_ro(amd_pstate_max_freq);
cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
cpufreq_freq_attr_ro(amd_pstate_highest_perf);
+cpufreq_freq_attr_ro(amd_pstate_hw_prefcore);
cpufreq_freq_attr_rw(energy_performance_preference);
cpufreq_freq_attr_ro(energy_performance_available_preferences);
static DEVICE_ATTR_RW(status);
+static DEVICE_ATTR_RO(prefcore);
static struct freq_attr *amd_pstate_attr[] = {
&amd_pstate_max_freq,
&amd_pstate_lowest_nonlinear_freq,
&amd_pstate_highest_perf,
+ &amd_pstate_hw_prefcore,
NULL,
};
@@ -1056,6 +1165,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
&amd_pstate_max_freq,
&amd_pstate_lowest_nonlinear_freq,
&amd_pstate_highest_perf,
+ &amd_pstate_hw_prefcore,
&energy_performance_preference,
&energy_performance_available_preferences,
NULL,
@@ -1063,6 +1173,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
static struct attribute *pstate_global_attributes[] = {
&dev_attr_status.attr,
+ &dev_attr_prefcore.attr,
NULL
};
@@ -1114,6 +1225,8 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
cpudata->cpu = policy->cpu;
cpudata->epp_policy = 0;
+ amd_pstate_init_prefcore(cpudata);
+
ret = amd_pstate_init_perf(cpudata);
if (ret)
goto free_cpudata1;
@@ -1527,7 +1640,17 @@ static int __init amd_pstate_param(char *str)
return amd_pstate_set_driver(mode_idx);
}
+
+static int __init amd_prefcore_param(char *str)
+{
+ if (!strcmp(str, "disable"))
+ amd_pstate_prefcore = false;
+
+ return 0;
+}
+
early_param("amd_pstate", amd_pstate_param);
+early_param("amd_prefcore", amd_prefcore_param);
MODULE_AUTHOR("Huang Rui ");
MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver");
diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
index 446394f84606..87e140e9e6db 100644
--- a/include/linux/amd-pstate.h
+++ b/include/linux/amd-pstate.h
@@ -52,6 +52,9 @@ struct amd_aperf_mperf {
* @prev: Last Aperf/Mperf/tsc count value read from register
* @freq: current cpu frequency value
* @boost_supported: check whether the Processor or SBIOS supports boost mode
+ * @hw_prefcore: check whether HW supports preferred core featue.
+ * Only when hw_prefcore and early prefcore param are true,
+ * AMD P-State driver supports preferred core featue.
* @epp_policy: Last saved policy used to set energy-performance preference
* @epp_cached: Cached CPPC energy-performance preference value
* @policy: Cpufreq policy value
@@ -81,6 +84,7 @@ struct amd_cpudata {
u64 freq;
bool boost_supported;
+ bool hw_prefcore;
/* EPP feature related attributes*/
s16 epp_policy;