From patchwork Tue Nov 14 23:05:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Jiang X-Patchwork-Id: 13456117 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 A8AE926AF7 for ; Tue, 14 Nov 2023 23:05:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="JU1WMmkz" Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 832D1D1 for ; Tue, 14 Nov 2023 15:05:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700003152; x=1731539152; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=JYPcOidqYIYQrOg3zO+RQWFE4cFR8xl+fv7KXNGeazc=; b=JU1WMmkzPLRp93Jfay1Ql9D/8DuB63WL3+ykhij7jjqydB8ajWkv/DF1 rqSTYnY7YgIeySZm/gP0IU++Uew6lAsQ2fOefdiJjvWCJNQg0yAhj7UIg ugtzJ7WPCUol94uUV2GlIqTiaz4BGSARLUMpXEOPU5FDzfctMMU1KY3Jo jzJF+kE848yFkRMcLkuRJOyoqAXDN4BhmyWTqemiuExR9hXaRnxT6D6BT cMJ8H7LM7YVVLaUB5orntj7bhVs46qDCb/mrC3zyLmSDFBmYwON1qUjl+ kXp3seX+Rt17t9gH3OUDvh1kY79FwFJY8paYMRBk9VWVHB1mREyHm4VuY w==; X-IronPort-AV: E=McAfee;i="6600,9927,10894"; a="12308558" X-IronPort-AV: E=Sophos;i="6.03,303,1694761200"; d="scan'208";a="12308558" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Nov 2023 15:05:52 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.03,303,1694761200"; d="scan'208";a="12586022" Received: from djiang5-mobl3.amr.corp.intel.com (HELO [192.168.1.177]) ([10.212.87.32]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Nov 2023 15:05:52 -0800 Subject: [PATCH v12 17/18] cxl: Export sysfs attributes for memory device QoS class From: Dave Jiang To: linux-cxl@vger.kernel.org Cc: Dan Williams , Jonathan Cameron , dan.j.williams@intel.com, ira.weiny@intel.com, vishal.l.verma@intel.com, alison.schofield@intel.com, Jonathan.Cameron@huawei.com, dave@stgolabs.net Date: Tue, 14 Nov 2023 16:05:51 -0700 Message-ID: <170000315132.1974471.14379811243633423568.stgit@djiang5-mobl3> In-Reply-To: <170000290509.1974471.16084327074615798619.stgit@djiang5-mobl3> References: <170000290509.1974471.16084327074615798619.stgit@djiang5-mobl3> User-Agent: StGit/1.5 Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Export qos_class sysfs attributes for the CXL memory device. The QoS clas should show up as /sys/bus/cxl/devices/memX/ram/qos_class for the volatile partition and /sys/bus/cxl/devices/memX/pmem/qos_class for the persistent partition. The QTG ID is retrieved via _DSM after supplying the calculated bandwidth and latency for the entire CXL path from device to the CPU. This ID is used to match up to the root decoder QoS class to determine which CFMWS the memory range of a hotplugged CXL mem device should be assigned under. While there may be multiple DSMAS exported by the device CDAT, the driver will only expose the first QTG ID per partition in sysfs for now. In the future when multiple QTG IDs are necessary, they can be exposed. [1] [1]: https://lore.kernel.org/linux-cxl/167571650007.587790.10040913293130712882.stgit@djiang5-mobl3.local/T/#md2a47b1ead3e1ba08f50eab29a4af1aed1d215ab Suggested-by: Dan Williams Reviewed-by: Jonathan Cameron Signed-off-by: Dave Jiang --- v12: - adjust to individual perf list --- Documentation/ABI/testing/sysfs-bus-cxl | 34 +++++++++++++++++++++++ drivers/cxl/core/memdev.c | 46 +++++++++++++++++++++++++++++++ 2 files changed, 80 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl index e76c3600607f..fff2581b8033 100644 --- a/Documentation/ABI/testing/sysfs-bus-cxl +++ b/Documentation/ABI/testing/sysfs-bus-cxl @@ -28,6 +28,23 @@ Description: Payload in the CXL-2.0 specification. +What: /sys/bus/cxl/devices/memX/ram/qos_class +Date: May, 2023 +KernelVersion: v6.8 +Contact: linux-cxl@vger.kernel.org +Description: + (RO) For CXL host platforms that support "QoS Telemmetry" + this attribute conveys a comma delimited list of platform + specific cookies that identifies a QoS performance class + for the volatile partition of the CXL mem device. These + class-ids can be compared against a similar "qos_class" + published for a root decoder. While it is not required + that the endpoints map their local memory-class to a + matching platform class, mismatches are not recommended + and there are platform specific performance related + side-effects that may result. First class-id is displayed. + + What: /sys/bus/cxl/devices/memX/pmem/size Date: December, 2020 KernelVersion: v5.12 @@ -38,6 +55,23 @@ Description: Payload in the CXL-2.0 specification. +What: /sys/bus/cxl/devices/memX/pmem/qos_class +Date: May, 2023 +KernelVersion: v6.8 +Contact: linux-cxl@vger.kernel.org +Description: + (RO) For CXL host platforms that support "QoS Telemmetry" + this attribute conveys a comma delimited list of platform + specific cookies that identifies a QoS performance class + for the persistent partition of the CXL mem device. These + class-ids can be compared against a similar "qos_class" + published for a root decoder. While it is not required + that the endpoints map their local memory-class to a + matching platform class, mismatches are not recommended + and there are platform specific performance related + side-effects that may result. First class-id is displayed. + + What: /sys/bus/cxl/devices/memX/serial Date: January, 2022 KernelVersion: v5.18 diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c index fc5c2b414793..4aed94c9f547 100644 --- a/drivers/cxl/core/memdev.c +++ b/drivers/cxl/core/memdev.c @@ -88,6 +88,28 @@ static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr, static struct device_attribute dev_attr_ram_size = __ATTR(size, 0444, ram_size_show, NULL); +static ssize_t ram_qos_class_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); + struct perf_prop_entry *perf; + + if (!dev->driver) + return -ENOENT; + + if (list_empty(&mds->ram_perf_list)) + return -ENOENT; + + perf = list_first_entry(&mds->ram_perf_list, struct perf_prop_entry, list); + + return sysfs_emit(buf, "%d\n", perf->qos_class); +} + +static struct device_attribute dev_attr_ram_qos_class = + __ATTR(qos_class, 0444, ram_qos_class_show, NULL); + static ssize_t pmem_size_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -101,6 +123,28 @@ static ssize_t pmem_size_show(struct device *dev, struct device_attribute *attr, static struct device_attribute dev_attr_pmem_size = __ATTR(size, 0444, pmem_size_show, NULL); +static ssize_t pmem_qos_class_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); + struct perf_prop_entry *perf; + + if (!dev->driver) + return -ENOENT; + + if (list_empty(&mds->pmem_perf_list)) + return -ENOENT; + + perf = list_first_entry(&mds->pmem_perf_list, struct perf_prop_entry, list); + + return sysfs_emit(buf, "%d\n", perf->qos_class); +} + +static struct device_attribute dev_attr_pmem_qos_class = + __ATTR(qos_class, 0444, pmem_qos_class_show, NULL); + static ssize_t serial_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -428,11 +472,13 @@ static struct attribute *cxl_memdev_attributes[] = { static struct attribute *cxl_memdev_pmem_attributes[] = { &dev_attr_pmem_size.attr, + &dev_attr_pmem_qos_class.attr, NULL, }; static struct attribute *cxl_memdev_ram_attributes[] = { &dev_attr_ram_size.attr, + &dev_attr_ram_qos_class.attr, NULL, };