Move PGO git logistics to a dedicated script.

This was unwieldy to have in the BuildKite pipeline directly, and variable
expansion didn't seem to work.

PiperOrigin-RevId: 771233792

Author: EtiennePerot

.buildkite/pgo.yaml

@@ -24,27 +24,6 @@ steps:
     if: build.branch == "master" && build.tag == null
     commands:
       - make ARCH=x86_64 benchmark-refresh-pgo BENCHMARKS_PLATFORMS=systrap
-      - '
-        if [[ "$(git status --porcelain | wc -l)" -gt 0 ]]; then
-          today="$(date +"%Y-%m-%d")" &&
-          pgo_branch_name="pgo-update-${today}" &&
-          git stash &&
-          git pull --rebase=true https://github.com/google/gvisor master &&
-          git checkout -b "$pgo_branch_name" &&
-          git add runsc/profiles &&
-          git status &&
-          gh auth login --with-token < "$HOME/.github-token" &&
-          gh auth setup-git &&
-          export GIT_AUTHOR_NAME=gvisor-bot &&
-          export GIT_AUTHOR_EMAIL=gvisor-bot@google.com &&
-          export GIT_COMMITTER_NAME=gvisor-bot &&
-          export GIT_COMMITTER_EMAIL=gvisor-bot@google.com &&
-          git commit -m "Update runsc profiles for PGO (profile-guided optimizations), $today." &&
-          git push --set-upstream git@github.com:google/gvisor.git "$pgo_branch_name" &&
-          gh pr create --title="Update runsc profiles for PGO (profile-guided optimizations), $today." --body="This PR updates the runsc profiles for PGO (profile-guided optimizations)." --label=pgo-update --base=master;
-        else
-          echo "No changes to runsc profiles." >&2;
-        fi
-        '
+      - ./.buildkite/scripts/pgo/commit-update.sh
     agents:
       arch: "amd64"

.buildkite/scripts/pgo/commit-update.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+
+# Copyright 2025 The gVisor 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.
+
+set -euxo pipefail
+
+if [[ "$(git status --porcelain | wc -l)" == 0 ]]; then
+  echo "No changes to runsc profiles." >&2
+  exit 0
+fi
+
+today="$(date +"%Y-%m-%d")"
+pgo_branch_name="pgo-update-${today}"
+git stash
+git pull --rebase=true https://github.com/google/gvisor master
+git checkout -b "$pgo_branch_name"
+git stash pop
+git add runsc/profiles
+git status
+gh auth login --with-token < "$HOME/.github-token"
+gh auth setup-git
+export GIT_AUTHOR_NAME=gvisor-bot
+export GIT_AUTHOR_EMAIL=gvisor-bot@google.com
+export GIT_COMMITTER_NAME=gvisor-bot
+export GIT_COMMITTER_EMAIL=gvisor-bot@google.com
+git commit -m "Update runsc profiles for PGO (profile-guided optimizations), $today."
+git push --set-upstream git@github.com:google/gvisor.git "$pgo_branch_name"
+gh pr create \
+  --title="Update runsc profiles for PGO (profile-guided optimizations), $today." \
+  --body='This PR updates the runsc profiles for PGO (profile-guided optimizations).' \
+  --label=pgo-update --base=master
+echo 'PGO profile update PR created.' >&2