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This is 3 orders of magnitude more than Nouveau (which sleeps for 1 microsecond) or OpenRM (which does not sleep at all and busy-polls) and is way too much, as GSP commands are expected to be processed much faster than that. Reduce the sleep time to 1 microsecond. This effectively makes `fsleep` busy-loop with a call to `cpu_relax` afterwards, keeping latency to a minimum. Signed-off-by: Alexandre Courbot --- Changes in v2: - Wait for 1 microsecond. (Eliot) - Link to v1: https://patch.msgid.link/20261030-cmdq_wait_msg_timeout-v1-1-a1e628d2732c@nvidia.com --- drivers/gpu/nova-core/gsp/cmdq.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/nova-core/gsp/cmdq.rs b/drivers/gpu/nova-core/gsp/cmdq.rs index 936406004a57..8ee8a99e4d7e 100644 --- a/drivers/gpu/nova-core/gsp/cmdq.rs +++ b/drivers/gpu/nova-core/gsp/cmdq.rs @@ -603,7 +603,7 @@ fn wait_for_msg(&self, timeout: Delta) -> Result> { read_poll_timeout( || Ok(self.gsp_mem.driver_read_area()), |driver_area| !driver_area.0.is_empty(), - Delta::from_millis(1), + Delta::from_micros(1), timeout, ) } --- base-commit: 9fe580fd90e20c8432832c5f9a7e92b049ae9af6 change-id: 20261030-cmdq_wait_msg_timeout-26df11234d10 Best regards, -- Alexandre Courbot