Update end-to-end test for aarch64 (#2415)

Fix up handling of CPU info collector on non-x86_64 systems due to
fixtures containing `/proc/cpuinfo` from x86_64.
* Update e2e 64k page test fixture from an arm64 system.
* Enable ARM testing in CircleCI.

Fixes: https://github.com/prometheus/node_exporter/issues/1959

Signed-off-by: Ben Kochie <superq@gmail.com>

.circleci/config.yml

@@ -8,6 +8,11 @@ executors:
   golang:
     docker:
       - image: cimg/go:1.18
+  arm:
+    machine:
+      image: ubuntu-2004:current
+    resource_class: arm.medium
+
 jobs:
   test:
     executor: golang
@@ -17,6 +22,12 @@ jobs:
       - run: make
       - prometheus/store_artifact:
           file: node_exporter
+  test-arm:
+    executor: arm
+    steps:
+      - checkout
+      - run: uname -a
+      - run: make test-e2e
   codespell:
     docker:
       - image: circleci/python
@@ -86,6 +97,10 @@ workflows:
           filters:
             tags:
               only: /.*/
+      - test-arm:
+          filters:
+            tags:
+              only: /.*/
       - build:
           filters:
             tags:

end-to-end-test.sh

@@ -71,6 +71,20 @@ case "${arch}" in
   *) fixture='collector/fixtures/e2e-output.txt' ;;
 esac
 
+# Only test CPU info collection on x86_64.
+case "${arch}" in
+  x86_64)
+    cpu_info_collector='--collector.cpu.info'
+    cpu_info_bugs='^(cpu_meltdown|spectre_.*|mds)$'
+    cpu_info_flags='^(aes|avx.?|constant_tsc)$'
+    ;;
+  *)
+    cpu_info_collector='--no-collector.cpu.info'
+    cpu_info_bugs=''
+    cpu_info_flags=''
+    ;;
+esac
+
 keep=0; update=0; verbose=0
 while getopts 'hkuv' opt
 do
@@ -114,9 +128,9 @@ fi
   --collector.netclass.ignored-devices="(dmz|int)" \
   --collector.netclass.ignore-invalid-speed \
   --collector.bcache.priorityStats \
-  --collector.cpu.info \
-  --collector.cpu.info.flags-include="^(aes|avx.?|constant_tsc)$" \
-  --collector.cpu.info.bugs-include="^(cpu_meltdown|spectre_.*|mds)$" \
+  "${cpu_info_collector}" \
+  --collector.cpu.info.bugs-include="${cpu_info_bugs}" \
+  --collector.cpu.info.flags-include="${cpu_info_flags}" \
   --collector.stat.softirq \
   --web.listen-address "127.0.0.1:${port}" \
   --log.level="debug" > "${tmpdir}/node_exporter.log" 2>&1 &