[PATCH net-next v4 0/4] netdevsim: implement RX statistics using NETDEV_PCPU_STAT_DSTATS

[Breno Leitao <leitao@debian.org>]

The netdevsim driver previously lacked RX statistics support, which
prevented its use with the GenerateTraffic() test framework, as this
framework verifies traffic flow by checking RX byte counts.

This patch migrates netdevsim from its custom statistics collection to
the NETDEV_PCPU_STAT_DSTATS framework, as suggested by Jakub. This
change not only standardizes the statistics handling but also adds the
necessary RX statistics support required by the test framework.

Signed-off-by: Breno Leitao <leitao@debian.org>
---
Changes in v4:
- Protect dev_dstats_rx_dropped_add() by disabling BH (Jakub)
- Link to v3: https://lore.kernel.org/r/20250617-netdevsim_stat-v3-0-afe4bdcbf237@debian.org

Changes in v3:
- Rely on netdev from caller instead of napi->dev in nsim_queue_free().
- Link to v2: https://lore.kernel.org/r/20250613-netdevsim_stat-v2-0-98fa38836c48@debian.org

Changes in v2:
- Changed the RX collection place from nsim_napi_rx() to nsim_rcv (Joe Damato)
- Collect RX dropped packets statistic in nsim_queue_free() (Jakub)
- Added a helper in dstat to add values to RX dropped packets
- Link to v1: https://lore.kernel.org/r/20250611-netdevsim_stat-v1-0-c11b657d96bf@debian.org

---
Breno Leitao (4):
      netdevsim: migrate to dstats stats collection
      netdevsim: collect statistics at RX side
      net: add dev_dstats_rx_dropped_add() helper
      netdevsim: account dropped packet length in stats on queue free

 drivers/net/netdevsim/netdev.c    | 56 ++++++++++++++++-----------------------
 drivers/net/netdevsim/netdevsim.h |  5 ----
 include/linux/netdevice.h         | 10 +++++++
 3 files changed, 33 insertions(+), 38 deletions(-)
---
base-commit: 3b5b1c428260152e47c9584bc176f358b87ca82d
change-id: 20250610-netdevsim_stat-95995921e03e

Best regards,
-- 
Breno Leitao <leitao@debian.org>