Re: [PATCH v6 0/3] spi: tegra210-quad: Improve interrupt handling for loaded systems

[Mark Brown]

On Thu, 13 Aug 2026 20:00:24 +0000, Vishwaroop A wrote:
> spi: tegra210-quad: Improve interrupt handling for loaded systems
> 
> The current threaded IRQ implementation in spi-tegra210-quad suffers
> from scheduler-induced latency on heavily loaded systems. The old
> irq_thread() runs SCHED_FIFO but is pinned by the kernel to the IRQ
> affinity mask (typically one CPU); when that CPU is saturated by RT
> workloads (e.g. NCCL multicast) or by an SPI transaction coming from
> a higher-priority context, the sleeping DMA/PIO wait inside the IRQ
> thread cannot progress and wait_for_completion_timeout() in
> transfer_one_message expires - even though the QSPI hardware
> finished on time. This results in false timeout errors and WARN_ON
> splats during normal operation.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-7.4

Thanks!

[1/3] spi: tegra210-quad: Convert to hard IRQ with high-priority workqueue
      https://git.kernel.org/broonie/sound/c/e329b94b1e47
[2/3] spi: tegra210-quad: Cache TRANS_STATUS in ISR for timeout handler
      https://git.kernel.org/broonie/sound/c/1ff82c13ea94
[3/3] spi: tegra210-quad: Process small PIO transfers in hard IRQ context
      https://git.kernel.org/broonie/sound/c/252ee24aff97

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
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Thanks,
Mark