Re: [PATCH 00/14] can: m_can: Optimizations for m_can/tcan part 2

From: Markus Schneider-Pargmann
Date: Wed Feb 07 2024 - 04:39:28 EST


Sorry, this is of course v7, forgot to add --reroll-count.

Best,
Markus

On Wed, Feb 07, 2024 at 10:32:06AM +0100, Markus Schneider-Pargmann wrote:
> Hi Marc, Simon, Martin and everyone,
>
> v7 is a rebase on v6.8. During my am62 tests I discovered some problems
> which are fixed with this update.
>
> @Simon: I had to remove most of your reviews again, due to a few
> fixes I made.
>
> The series implements many small and bigger throughput improvements and
> adds rx/tx coalescing at the end.
>
> Based on v6.8-rc1. Also available at
> https://gitlab.baylibre.com/msp8/linux/-/tree/topic/mcan-optimization/v6.8?ref_type=heads
>
> Best,
> Markus
>
> Changes in v7:
> - Rebased to v6.8-rc1
> - Fixed NULL pointer dereference in m_can_clean() on am62 that happened
> when doing ip link up, ip link down, ip link up
> - Fixed a racecondition on am62 observed with high throughput tests.
> netdev_completed_queue() was called before netdev_sent_queue() as the
> interrupt was processed so fast. netdev_sent_queue() is now reported
> before the actual sent is done.
> - Fixed an initializing issue on am62 where active interrupts are
> getting lost between runs. Fixed by resetting cdev->active_interrupts
> in m_can_disable_all_interrupts()
> - Removed m_can_start_fast_xmit() because of a reordering of operations
> due to above mentioned racecondition
>
> Changes in v6:
> - Rebased to v6.6-rc2
> - Added two small changes for the newly integrated polling feature
> - Reuse the polling hrtimer for coalescing as the timer used for
> coalescing has a similar purpose as the one for polling. Also polling
> and coalescing will never be active at the same time.
>
> Changes in v5:
> - Add back parenthesis in m_can_set_coalesce(). This will make
> checkpatch unhappy but gcc happy.
> - Remove unused fifo_header variable in m_can_tx_handler().
> - Rebased to v6.5-rc1
>
> Changes in v4:
> - Create and use struct m_can_fifo_element in m_can_tx_handler
> - Fix memcpy_and_pad to copy the full buffer
> - Fixed a few checkpatch warnings
> - Change putidx to be unsigned
> - Print hard_xmit error only once when TX FIFO is full
>
> Changes in v3:
> - Remove parenthesis in error messages
> - Use memcpy_and_pad for buffer copy in 'can: m_can: Write transmit
> header and data in one transaction'.
> - Replace spin_lock with spin_lock_irqsave. I got a report of a
> interrupt that was calling start_xmit just after the netqueue was
> woken up before the locked region was exited. spin_lock_irqsave should
> fix this. I attached the full stack at the end of the mail if someone
> wants to know.
> - Rebased to v6.3-rc1.
> - Removed tcan4x5x patches from this series.
>
> Changes in v2:
> - Rebased on v6.2-rc5
> - Fixed missing/broken accounting for non peripheral m_can devices.
>
> previous versions:
> v1 - https://lore.kernel.org/lkml/20221221152537.751564-1-msp@xxxxxxxxxxxx
> v2 - https://lore.kernel.org/lkml/20230125195059.630377-1-msp@xxxxxxxxxxxx
> v3 - https://lore.kernel.org/lkml/20230315110546.2518305-1-msp@xxxxxxxxxxxx/
> v4 - https://lore.kernel.org/lkml/20230621092350.3130866-1-msp@xxxxxxxxxxxx/
> v5 - https://lore.kernel.org/lkml/20230718075708.958094-1-msp@xxxxxxxxxxxx
> v6 - https://lore.kernel.org/lkml/20230929141304.3934380-1-msp@xxxxxxxxxxxx
>
> Markus Schneider-Pargmann (14):
> can: m_can: Start/Cancel polling timer together with interrupts
> can: m_can: Move hrtimer init to m_can_class_register
> can: m_can: Write transmit header and data in one transaction
> can: m_can: Implement receive coalescing
> can: m_can: Implement transmit coalescing
> can: m_can: Add rx coalescing ethtool support
> can: m_can: Add tx coalescing ethtool support
> can: m_can: Use u32 for putidx
> can: m_can: Cache tx putidx
> can: m_can: Use the workqueue as queue
> can: m_can: Introduce a tx_fifo_in_flight counter
> can: m_can: Use tx_fifo_in_flight for netif_queue control
> can: m_can: Implement BQL
> can: m_can: Implement transmit submission coalescing
>
> drivers/net/can/m_can/m_can.c | 551 ++++++++++++++++++-------
> drivers/net/can/m_can/m_can.h | 34 +-
> drivers/net/can/m_can/m_can_platform.c | 4 -
> 3 files changed, 439 insertions(+), 150 deletions(-)
>
> --
> 2.43.0
>