On Fri, Jun 27, 2025 at 12:23:29PM +0100, James Clark wrote:
On 27/06/2025 12:10 pm, Yuanfang Zhang wrote:
The current implementation uses a fixed timeout via coresight_timeout(), which may be insufficient when multiple sources are enabled or under heavy load, leading to TMC readiness or flush completion timeout.
This patch introduces a configurable timeout mechanism for flush and tmcready.
What kind of values are you using? Is there a reason to not increase the global one?
IIUC, this patch is related to patch [1].
It seems to me that both patches aim to address the long latency when flushing the TMC, but take different approaches. In the earlier patch, both Mike and I questioned how the timeout occurred in hardware, but no information provided about the cause.
I would suggest that we first make clear if this is a hardware quirk or a common issue in Arm CoreSight.
Thanks, Leo
[1] https://lore.kernel.org/linux-arm-kernel/CAJ9a7Vgre_3mkXB_xeVx5N9BqPTa2Ai4_8...