Add nvme collector

Add a collector for NVMes to expose the firmware versions. This requires
procfs >= 0.7.0.

Fixes #1891
Signed-off-by: Benjamin Drung <benjamin.drung@ionos.com>

README.md

@@ -113,6 +113,7 @@ netdev | Exposes network interface statistics such as bytes transferred. | Darwi
 netstat | Exposes network statistics from `/proc/net/netstat`. This is the same information as `netstat -s`. | Linux
 nfs | Exposes NFS client statistics from `/proc/net/rpc/nfs`. This is the same information as `nfsstat -c`. | Linux
 nfsd | Exposes NFS kernel server statistics from `/proc/net/rpc/nfsd`. This is the same information as `nfsstat -s`. | Linux
+nvme | Exposes NVMe info from `/sys/class/nvme/` | Linux
 powersupplyclass | Exposes Power Supply statistics from `/sys/class/power_supply` | Linux
 pressure | Exposes pressure stall statistics from `/proc/pressure/`. | Linux (kernel 4.20+ and/or [CONFIG\_PSI](https://www.kernel.org/doc/html/latest/accounting/psi.html))
 rapl | Exposes various statistics from `/sys/class/powercap`. | Linux

collector/fixtures/e2e-64k-page-output.txt

@@ -2439,6 +2439,9 @@ node_nfsd_server_rpcs_total 18628
 # HELP node_nfsd_server_threads Total number of NFSd kernel threads that are running.
 # TYPE node_nfsd_server_threads gauge
 node_nfsd_server_threads 8
+# HELP node_nvme_info Non-numeric data from /sys/class/nvme/<device>, value is always 1.
+# TYPE node_nvme_info gauge
+node_nvme_info{device="nvme0",firmware_revision="1B2QEXP7",model="Samsung SSD 970 PRO 512GB",serial="S680HF8N190894I",state="live"} 1
 # HELP node_power_supply_capacity capacity value of /sys/class/power_supply/<power_supply>.
 # TYPE node_power_supply_capacity gauge
 node_power_supply_capacity{power_supply="BAT0"} 81
@@ -2586,6 +2589,7 @@ node_scrape_collector_success{collector="netdev"} 1
 node_scrape_collector_success{collector="netstat"} 1
 node_scrape_collector_success{collector="nfs"} 1
 node_scrape_collector_success{collector="nfsd"} 1
+node_scrape_collector_success{collector="nvme"} 1
 node_scrape_collector_success{collector="powersupplyclass"} 1
 node_scrape_collector_success{collector="pressure"} 1
 node_scrape_collector_success{collector="processes"} 1

collector/fixtures/e2e-output.txt

@@ -2637,6 +2637,9 @@ node_nfsd_server_rpcs_total 18628
 # HELP node_nfsd_server_threads Total number of NFSd kernel threads that are running.
 # TYPE node_nfsd_server_threads gauge
 node_nfsd_server_threads 8
+# HELP node_nvme_info Non-numeric data from /sys/class/nvme/<device>, value is always 1.
+# TYPE node_nvme_info gauge
+node_nvme_info{device="nvme0",firmware_revision="1B2QEXP7",model="Samsung SSD 970 PRO 512GB",serial="S680HF8N190894I",state="live"} 1
 # HELP node_power_supply_capacity capacity value of /sys/class/power_supply/<power_supply>.
 # TYPE node_power_supply_capacity gauge
 node_power_supply_capacity{power_supply="BAT0"} 81
@@ -2787,6 +2790,7 @@ node_scrape_collector_success{collector="netdev"} 1
 node_scrape_collector_success{collector="netstat"} 1
 node_scrape_collector_success{collector="nfs"} 1
 node_scrape_collector_success{collector="nfsd"} 1
+node_scrape_collector_success{collector="nvme"} 1
 node_scrape_collector_success{collector="powersupplyclass"} 1
 node_scrape_collector_success{collector="pressure"} 1
 node_scrape_collector_success{collector="processes"} 1

collector/fixtures/sys.ttar

@@ -1124,6 +1124,32 @@ Lines: 1
 1
 Mode: 644
 # ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Directory: sys/class/nvme
+Mode: 755
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Directory: sys/class/nvme/nvme0
+Mode: 755
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: sys/class/nvme/nvme0/firmware_rev
+Lines: 1
+1B2QEXP7
+Mode: 444
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: sys/class/nvme/nvme0/model
+Lines: 1
+Samsung SSD 970 PRO 512GB               
+Mode: 444
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: sys/class/nvme/nvme0/serial
+Lines: 1
+S680HF8N190894I
+Mode: 444
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Path: sys/class/nvme/nvme0/state
+Lines: 1
+live
+Mode: 444
+# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 Directory: sys/class/power_supply
 Mode: 755
 # ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

collector/nvme_linux.go

@@ -0,0 +1,74 @@
+// Copyright 2021 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build linux
+// +build !nonvme
+
+package collector
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/go-kit/log"
+	"github.com/go-kit/log/level"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/procfs/sysfs"
+)
+
+type nvmeCollector struct {
+	fs     sysfs.FS
+	logger log.Logger
+}
+
+func init() {
+	registerCollector("nvme", defaultEnabled, NewNVMeCollector)
+}
+
+// NewNVMeCollector returns a new Collector exposing NVMe stats.
+func NewNVMeCollector(logger log.Logger) (Collector, error) {
+	fs, err := sysfs.NewFS(*sysPath)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open sysfs: %w", err)
+	}
+
+	return &nvmeCollector{
+		fs:     fs,
+		logger: logger,
+	}, nil
+}
+
+func (c *nvmeCollector) Update(ch chan<- prometheus.Metric) error {
+	devices, err := c.fs.NVMeClass()
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			level.Debug(c.logger).Log("msg", "nvme statistics not found, skipping")
+			return ErrNoData
+		}
+		return fmt.Errorf("error obtaining NVMe class info: %w", err)
+	}
+
+	for _, device := range devices {
+		infoDesc := prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, "nvme", "info"),
+			"Non-numeric data from /sys/class/nvme/<device>, value is always 1.",
+			[]string{"device", "firmware_revision", "model", "serial", "state"},
+			nil,
+		)
+		infoValue := 1.0
+		ch <- prometheus.MustNewConstMetric(infoDesc, prometheus.GaugeValue, infoValue, device.Name, device.FirmwareRevision, device.Model, device.Serial, device.State)
+	}
+
+	return nil
+}

go.mod

@@ -16,7 +16,7 @@ require (
 	github.com/prometheus/client_model v0.2.0
 	github.com/prometheus/common v0.26.0
 	github.com/prometheus/exporter-toolkit v0.5.1
-	github.com/prometheus/procfs v0.6.0
+	github.com/prometheus/procfs v0.7.0
 	github.com/safchain/ethtool v0.0.0-20200804214954-8f958a28363a
 	github.com/siebenmann/go-kstat v0.0.0-20200303194639-4e8294f9e9d5
 	github.com/soundcloud/go-runit v0.0.0-20150630195641-06ad41a06c4a

go.sum

@@ -281,8 +281,8 @@ github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsT
 github.com/prometheus/procfs v0.0.8/go.mod h1:7Qr8sr6344vo1JqZ6HhLceV9o3AJ1Ff+GxbHq6oeK9A=
 github.com/prometheus/procfs v0.1.3/go.mod h1:lV6e/gmhEcM9IjHGsFOCxxuZ+z1YqCvr4OA4YeYWdaU=
 github.com/prometheus/procfs v0.2.0/go.mod h1:lV6e/gmhEcM9IjHGsFOCxxuZ+z1YqCvr4OA4YeYWdaU=
-github.com/prometheus/procfs v0.6.0 h1:mxy4L2jP6qMonqmq+aTtOx1ifVWUgG/TAmntgbh3xv4=
+github.com/prometheus/procfs v0.7.0 h1:OQZ41sZU9XkRpzrz8/TD0EldH/Rwbddkdu5wDyUwzfE=
-github.com/prometheus/procfs v0.6.0/go.mod h1:cz+aTbrPOrUb4q7XlbU9ygM+/jj0fzG6c1xBZuNvfVA=
+github.com/prometheus/procfs v0.7.0/go.mod h1:cz+aTbrPOrUb4q7XlbU9ygM+/jj0fzG6c1xBZuNvfVA=
 github.com/rcrowley/go-metrics v0.0.0-20181016184325-3113b8401b8a/go.mod h1:bCqnVzQkZxMG4s8nGwiZ5l3QUCyqpo9Y+/ZMZ9VjZe4=
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=