From:   Kai-Heng Feng <kai.heng.feng@canonical.com>
To:     hkallweit1@gmail.com, nic_swsd@realtek.com, bhelgaas@google.com
Cc:     koba.ko@canonical.com, acelan.kao@canonical.com,
        davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com, sathyanarayanan.kuppuswamy@linux.intel.com,
        vidyas@nvidia.com, rafael.j.wysocki@intel.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-pci@vger.kernel.org,
        Kai-Heng Feng <kai.heng.feng@canonical.com>
Subject: [PATCH net-next v9 0/5] r8169: Temporarily disable ASPM on NAPI poll
Date:   Sat, 25 Feb 2023 11:46:30 +0800
Message-Id: <20230225034635.2220386-1-kai.heng.feng@canonical.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

The series is to temporarily disable ASPM on NAPI poll, so the NIC can
"regain" the performace loss when ASPM is enabled. The idea is from
Realtek vendor driver's feature "dynamic ASPM" .

We have "dynamic ASPM" mechanism in Ubuntu 22.04 LTS kernel for quite a
while, and AFAIK it hasn't introduced any regression so far. 

A very similar issue was observed on Realtek wireless NIC, and it was
resolved by disabling ASPM during NAPI poll. So in v8 and v9, we use the
same approach, which is more straightforward, instead of toggling ASPM
based on packet count.

In addition to that, The series also enables ASPM on more systems where
BIOS doesn't grant OS ASPM control.

v8:
https://lore.kernel.org/netdev/20230221023849.1906728-1-kai.heng.feng@canonical.com/

v7:
https://lore.kernel.org/netdev/20211016075442.650311-1-kai.heng.feng@canonical.com/

v6:
https://lore.kernel.org/netdev/20211007161552.272771-1-kai.heng.feng@canonical.com/

v5:
https://lore.kernel.org/netdev/20210916154417.664323-1-kai.heng.feng@canonical.com/

v4:
https://lore.kernel.org/netdev/20210827171452.217123-1-kai.heng.feng@canonical.com/

v3:
https://lore.kernel.org/netdev/20210819054542.608745-1-kai.heng.feng@canonical.com/

v2:
https://lore.kernel.org/netdev/20210812155341.817031-1-kai.heng.feng@canonical.com/

v1:
https://lore.kernel.org/netdev/20210803152823.515849-1-kai.heng.feng@canonical.com/

Kai-Heng Feng (5):
  Revert "PCI/ASPM: Unexport pcie_aspm_support_enabled()"
  PCI/ASPM: Add pcie_aspm_capable() helper
  r8169: Consider chip-specific ASPM can be enabled on more cases
  r8169: Use spinlock to guard config register locking
  r8169: Disable ASPM while doing NAPI poll

 drivers/net/ethernet/realtek/r8169_main.c | 42 +++++++++++++++++++----
 drivers/pci/pcie/aspm.c                   | 12 +++++++
 include/linux/pci.h                       |  2 ++
 3 files changed, 50 insertions(+), 6 deletions(-)

-- 
2.34.1