|SUCCESS| net/dpaa2: drop the fake software VLAN strip offload

[dpdklab at iol.unh.edu]

Test-Label: ai-code-review
Test-Status: SUCCESS
https://dpdk.org/patch/166419

_AI Code Review_

=== Patch Review: series.patch (via Claude) ===
Review date: 2026-06-30

# DPDK Patch Review

## Summary

This patch removes fake software VLAN strip offload from the dpaa2 driver. The changes are correct and the reasoning is sound - moving software VLAN stripping from the driver to the application where the L2 header is already being read. No errors or warnings found.

## Detailed Analysis

### Correctness
 No resource leaks
 No use-after-free issues
 No race conditions
 No undefined behavior
 Error paths are not applicable (code removal only)

### Code Style
 No forbidden tokens introduced
 No style violations
 Consistent with existing code formatting
 Proper indentation maintained

### API and Documentation
 Release notes updated appropriately in `release_26_07.rst`
 Behavioral change is documented (applications must now strip VLAN tags themselves)
 Removal of `RTE_ETH_RX_OFFLOAD_VLAN_STRIP` from supported offloads is correct
 No new API added (removal only)

### Functional Review
 Removes inefficient software path that caused cache misses
 Performance improvement is well-justified with measurements
 Removal is from both Rx paths (`dpaa2_dev_prefetch_rx` and `dpaa2_dev_rx`)
 Consistent removal across all code paths

### Process Compliance
 Patch targets current development release (26.07)
 Has appropriate Acked-by tags
 Release notes placement is correct (under driver-specific updates)

## Notes

The patch correctly identifies and removes a performance anti-pattern where software VLAN stripping in the driver causes unnecessary cache misses on cold mbuf and packet data. The measured performance improvement (+18% throughput, -37% L2 cache misses) validates the change. Applications that need VLAN tags removed will now need to call `rte_vlan_strip()` themselves, which they can do after they've already read the L2 header for forwarding decisions, avoiding the cache miss penalty.

No issues found.