[diffusion] CI: add 5090 job (#29791)

.github/workflows/pr-test-multimodal-gen.yml

@@ -144,6 +144,69 @@ jobs:
         with:
           artifact-suffix: ${{ matrix.part }}
 
+  multimodal-gen-test-1-5090:
+    if: |
+      ((github.event_name == 'schedule' || inputs.test_parallel_dispatch == 'true') || (inputs.caller_needs_failure != 'true' && !cancelled())) &&
+      inputs.multimodal_gen == 'true'
+    runs-on: 1-gpu-5090
+    timeout-minutes: 180
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.git_ref || github.sha }}
+
+      - uses: ./.github/actions/check-pr-test-health
+
+      - uses: ./.github/actions/check-maintenance
+
+      - name: Download artifacts
+        if: inputs.sgl_kernel == 'true'
+        uses: actions/download-artifact@v4
+        with:
+          path: sgl-kernel/dist/
+          merge-multiple: true
+          pattern: wheel-python3.10-cuda*
+
+      - name: Install dependencies
+        timeout-minutes: 20
+        run: |
+          CUSTOM_BUILD_SGL_KERNEL=${{inputs.sgl_kernel}} bash scripts/ci/cuda/ci_install_dependency.sh diffusion
+
+      - name: Run 5090 diffusion canary tests
+        timeout-minutes: 120
+        env:
+          RUNAI_STREAMER_MEMORY_LIMIT: 0
+          CONTINUE_ON_ERROR_FLAG: ${{ inputs.continue_on_error == 'true' && '--continue-on-error' || '' }}
+          SGLANG_DIFFUSION_ARTIFACT_DIR: ${{ github.workspace }}/diffusion-failures
+        run: |
+          cd python
+          python3 sglang/multimodal_gen/test/run_suite.py \
+            --suite 1-gpu-5090 \
+            $CONTINUE_ON_ERROR_FLAG
+
+      - name: Upload execution report
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: diffusion-5090-report-${{ github.run_attempt }}
+          path: python/sglang/multimodal_gen/test/execution_report_*.json
+          retention-days: 7
+
+      - name: Upload diffusion failure artifacts
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: diffusion-failures-5090-${{ github.run_attempt }}
+          path: diffusion-failures/
+          if-no-files-found: ignore
+          retention-days: 7
+
+      - uses: ./.github/actions/upload-cuda-coredumps
+        if: failure()
+        with:
+          artifact-suffix: 1-gpu-5090
+
   multimodal-gen-test-2-gpu:
     needs: compute-diffusion-partitions
     if: |