Fix kselftest base branch comparing

Signed-off-by: Shreeya Patel <spatel@ciq.com>

Author: shreeya-patel98

.github/workflows/kernel-build-and-test-x86_64.yml

@@ -205,33 +205,64 @@ jobs:
         name: kselftest-logs-x86_64
         path: output-current
 
-    - name: Download previous kselftest logs
+    - name: Determine base branch for comparison
+      id: base_branch
+      run: |
+        # Determine base branch from the upstream tracking branch
+        BASE_BRANCH=$(git rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null | sed 's|^origin/||' || echo "")
+
+        if [ -z "$BASE_BRANCH" ]; then
+          # Fallback: use merge-base to find the common ancestor branch
+          echo "No upstream tracking branch found, using merge-base to find parent branch"
+          for branch in lts-9.2 lts-9 main master; do
+            if git rev-parse origin/$branch >/dev/null 2>&1; then
+              MERGE_BASE=$(git merge-base HEAD origin/$branch 2>/dev/null || echo "")
+              if [ -n "$MERGE_BASE" ]; then
+                BASE_BRANCH=$branch
+                echo "Found common ancestor with origin/$branch"
+                break
+              fi
+            fi
+          done
+        fi
+
+        if [ -z "$BASE_BRANCH" ]; then
+          echo "WARNING: Could not determine base branch, defaulting to main"
+          BASE_BRANCH="main"
+        fi
+
+        echo "base_branch=$BASE_BRANCH" >> $GITHUB_OUTPUT
+        echo "Base branch for comparison: $BASE_BRANCH"
+
+    - name: Download baseline kselftest logs from base branch
       uses: dawidd6/action-download-artifact@v3
       with:
         workflow: kernel-build-and-test-x86_64.yml
         name: kselftest-logs-x86_64
         path: output-previous
-        branch: ${{ github.ref_name }}
+        branch: ${{ steps.base_branch.outputs.base_branch }}
         workflow_conclusion: success
         search_artifacts: true
         skip_unpack: false
         if_no_artifact_found: warn
       continue-on-error: true
 
     - name: Compare test results
+      id: comparison
       run: |
-        if [ -f output-previous/kselftests-*.log ]; then
+        # Check if baseline logs exist
+        if ls output-previous/kselftests-*.log 1> /dev/null 2>&1; then
           # Compare passing tests (ok)
-          BEFORE_PASS=$(grep -a '^ok' output-previous/kselftests-*.log | wc -l)
-          AFTER_PASS=$(grep -a '^ok' output-current/kselftests-*.log | wc -l)
+          BEFORE_PASS=$(grep -a '^ok' output-previous/kselftests-*.log | wc -l || echo "0")
+          AFTER_PASS=$(grep -a '^ok' output-current/kselftests-*.log | wc -l || echo "0")
 
           # Compare failing tests (not ok)
-          BEFORE_FAIL=$(grep -a '^not ok' output-previous/kselftests-*.log | wc -l)
-          AFTER_FAIL=$(grep -a '^not ok' output-current/kselftests-*.log | wc -l)
+          BEFORE_FAIL=$(grep -a '^not ok' output-previous/kselftests-*.log | wc -l || echo "0")
+          AFTER_FAIL=$(grep -a '^not ok' output-current/kselftests-*.log | wc -l || echo "0")
 
-          echo "### Kselftest Comparison (Branch: ${{ github.ref_name }})"
-          echo "Passing tests: $BEFORE_PASS -> $AFTER_PASS"
-          echo "Failing tests: $BEFORE_FAIL -> $AFTER_FAIL"
+          echo "### Kselftest Comparison"
+          echo "Baseline (from ${{ steps.base_branch.outputs.base_branch }}): $BEFORE_PASS passing, $BEFORE_FAIL failing"
+          echo "Current (${{ github.ref_name }}): $AFTER_PASS passing, $AFTER_FAIL failing"
 
           # Calculate differences
           PASS_DIFF=$((AFTER_PASS - BEFORE_PASS))
@@ -255,21 +286,39 @@ jobs:
 
           if [ $REGRESSION -eq 1 ]; then
             echo "::error::Test regression exceeds acceptable threshold of 3 tests"
+            echo "comparison_status=failed" >> $GITHUB_OUTPUT
+            echo "comparison_message=Regression detected: Pass diff: $PASS_DIFF, Fail diff: $FAIL_DIFF (threshold: ±3)" >> $GITHUB_OUTPUT
             exit 1
           else
             echo "::notice::Test results within acceptable range (threshold: ±3 tests)"
+            echo "comparison_status=passed" >> $GITHUB_OUTPUT
+            echo "comparison_message=Baseline: $BEFORE_PASS passing, $BEFORE_FAIL failing | Current: $AFTER_PASS passing, $AFTER_FAIL failing" >> $GITHUB_OUTPUT
           fi
         else
-          echo "::warning::No previous successful test results found for branch ${{ github.ref_name }}, skipping comparison"
+          echo "::warning::No baseline test results found for branch ${{ steps.base_branch.outputs.base_branch }}"
+          echo "::notice::Cannot compare against base branch - artifacts may not exist or have expired (7-day retention)"
+          echo "::notice::Skipping comparison - PR will still be created with warning"
+          echo "comparison_status=skipped" >> $GITHUB_OUTPUT
+          echo "comparison_message=No baseline results available from ${{ steps.base_branch.outputs.base_branch }}" >> $GITHUB_OUTPUT
         fi
 
   create-pr:
     name: Create Pull Request
     runs-on: kernel-build
     needs: [build, boot, test-kselftest, compare-results]
-    if: success()
+    if: success() || failure()
 
     steps:
+    - name: Check if all stages passed
+      run: |
+        if [ "${{ needs.build.result }}" != "success" ] || \
+           [ "${{ needs.boot.result }}" != "success" ] || \
+           [ "${{ needs.test-kselftest.result }}" != "success" ]; then
+          echo "One or more test stages failed, skipping PR creation"
+          exit 1
+        fi
+        echo "All test stages passed, proceeding with PR creation"
+
     - name: Checkout kernel source
       uses: actions/checkout@v4
       with:
@@ -376,15 +425,28 @@ jobs:
 
         echo "Creating PR from ${{ github.ref_name }} to $BASE_BRANCH"
 
+        # Determine comparison status message
+        COMPARISON_RESULT="${{ needs.compare-results.result }}"
+        if [ "$COMPARISON_RESULT" = "success" ]; then
+          COMPARISON_SECTION="### ✅ Test Comparison
+        - Status: Passed - Within acceptable threshold (±3 tests)
+        - Compared against: $BASE_BRANCH"
+        else
+          COMPARISON_SECTION="### ⚠️ Test Comparison
+        - Status: Skipped
+        - Reason: No baseline test results available from $BASE_BRANCH
+        - **Note:** Manual review recommended to ensure no regressions"
+        fi
+
         # Create PR body
-        cat > pr_body.md << 'EOF'
+        cat > pr_body.md << EOF
         ## Summary
         This PR has been automatically created after successful completion of all CI stages.
 
         ## Commit Message(s)
-        ```
+        \`\`\`
         ${{ steps.commit_msg.outputs.commit_message }}
-        ```
+        \`\`\`
 
         ## Test Results
 
@@ -403,9 +465,7 @@ jobs:
         - **Failed:** ${{ steps.stats.outputs.failed }}
         - [View kselftest logs](https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }})
 
-        ### ✅ Test Comparison
-        - Comparison against previous run: Within acceptable threshold (±3 tests)
-        - Branch: ${{ github.ref_name }}
+        $COMPARISON_SECTION
 
         ---
         🤖 This PR was automatically generated by GitHub Actions