.buildkite: ensure consistent distro and host

This change should ensure that all critical steps in the pipeline run on
the same Linux distribution (since we want to test multiple
distributions) and on the same host (since we mutate state on that
host), but continue to allow steps to run in parallel on that host
(using multiple Buildkite agents).

Signed-off-by: Samuel Karp <[email protected]>

Author: samuelkarp

.buildkite/pipeline.yml

@@ -16,35 +16,54 @@ steps:
     command:
       - uname -a
       - go version
+    agents:
+      queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
+      distro: "${BUILDKITE_AGENT_META_DATA_DISTRO}"
+      hostname: "${BUILDKITE_AGENT_META_DATA_HOSTNAME}"
 
   - label: ':go: go mod download'
     command: 'go mod download'
     agents:
       queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
+      distro: "${BUILDKITE_AGENT_META_DATA_DISTRO}"
+      hostname: "${BUILDKITE_AGENT_META_DATA_HOSTNAME}"
 
   - label: ':linux: setup taps'
     commands:
       - 'sudo ip tuntap add fc-test-tap${BUILDKITE_BUILD_NUMBER} mode tap user $(sudo id -u buildkite-agent)'
       - 'sudo ip tuntap add fc-root-tap${BUILDKITE_BUILD_NUMBER} mode tap user $(sudo id -u buildkite-agent)'
     agents:
       queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
+      distro: "${BUILDKITE_AGENT_META_DATA_DISTRO}"
+      hostname: "${BUILDKITE_AGENT_META_DATA_HOSTNAME}"
 
   # We use a "wait" step here, because Go's module logic freaks out when
   # multiple go builds are downloading to the same cache.
   - wait
 
   - label: gofmt -s
     command: test -z $(gofmt -s -l .)
+    # This should run in the same queue, but we don't care whether it runs on
+    # the same host.
+    agents:
+      queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
 
   - label: 'git log validation'
     command: './.buildkite/logcheck.sh'
+    # This should run in the same queue, but we don't care whether it runs on
+    # the same host.
+    agents:
+      queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
 
   - label: 'build'
     commands:
       - 'make'
       - 'make -C cni'
     agents:
       queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
+      distro: "${BUILDKITE_AGENT_META_DATA_DISTRO}"
+      hostname: "${BUILDKITE_AGENT_META_DATA_HOSTNAME}"
+
 
   - label: ':hammer: tests'
     commands:
@@ -55,6 +74,9 @@ steps:
       - "FC_TEST_TAP=fc-test-tap${BUILDKITE_BUILD_NUMBER} make test EXTRAGOARGS='-v -count=1 -race' DISABLE_ROOT_TESTS=true"
     agents:
       queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
+      distro: "${BUILDKITE_AGENT_META_DATA_DISTRO}"
+      hostname: "${BUILDKITE_AGENT_META_DATA_HOSTNAME}"
+
 
   - label: ':hammer: root tests'
     commands:
@@ -66,6 +88,9 @@ steps:
       - "sudo FC_TEST_TAP=fc-root-tap${BUILDKITE_BUILD_NUMBER} make test EXTRAGOARGS='-v -count=1 -race' DISABLE_ROOT_TESTS="
     agents:
       queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
+      distro: "${BUILDKITE_AGENT_META_DATA_DISTRO}"
+      hostname: "${BUILDKITE_AGENT_META_DATA_HOSTNAME}"
+
 
   # This allows the cleanup step to always run, regardless of test failure
   - wait: ~
@@ -77,4 +102,7 @@ steps:
       - 'sudo ip tuntap del fc-root-tap${BUILDKITE_BUILD_NUMBER} mode tap'
     agents:
       queue: "${BUILDKITE_AGENT_META_DATA_QUEUE:-default}"
+      distro: "${BUILDKITE_AGENT_META_DATA_DISTRO}"
+      hostname: "${BUILDKITE_AGENT_META_DATA_HOSTNAME}"
+