gpu: host1x: syncpt_wait micro-optimizations

[PATCH 0/2] gpu: host1x: syncpt_wait micro-optimizations

Posted by Tanmay Patil 4 weeks, 1 day ago

This series reduces the latency in host1x syncpoint wait path.

Patch 1 removes redundant MMIO reads in host1x_syncpt_wait().
Patch 2 skips the host1x_intr_update_hw_state() call in the ISR
when no fences remain.

Measured syncpoint wait latency (50000 samples):
  Average latency:   12.2 us  -> 9.4 us
  99.99 pct latency: 62.96 us -> 36.58 us

Tanmay Patil (2):
  gpu: host1x: skip redundant syncpoint loads in host1x_syncpt_wait()
  gpu: host1x: skip redundant HW state update

 drivers/gpu/host1x/intr.c   |  8 ++++++--
 drivers/gpu/host1x/syncpt.c | 23 ++++++++++++++---------
 2 files changed, 20 insertions(+), 11 deletions(-)

-- 
2.54.0

Re: [PATCH 0/2] gpu: host1x: syncpt_wait micro-optimizations

Posted by Thierry Reding 2 weeks, 1 day ago

On Thu, May 14, 2026 at 10:31:51AM +0000, Tanmay Patil wrote:
> This series reduces the latency in host1x syncpoint wait path.
> 
> Patch 1 removes redundant MMIO reads in host1x_syncpt_wait().
> Patch 2 skips the host1x_intr_update_hw_state() call in the ISR
> when no fences remain.
> 
> Measured syncpoint wait latency (50000 samples):
>   Average latency:   12.2 us  -> 9.4 us
>   99.99 pct latency: 62.96 us -> 36.58 us
> 
> Tanmay Patil (2):
>   gpu: host1x: skip redundant syncpoint loads in host1x_syncpt_wait()
>   gpu: host1x: skip redundant HW state update

Both patches applied, thanks.

Thierry

Re: [PATCH 0/2] gpu: host1x: syncpt_wait micro-optimizations

Posted by Mikko Perttunen 2 weeks, 3 days ago

On Thursday, May 14, 2026 7:31 PM Tanmay Patil wrote:
> This series reduces the latency in host1x syncpoint wait path.
> 
> Patch 1 removes redundant MMIO reads in host1x_syncpt_wait().
> Patch 2 skips the host1x_intr_update_hw_state() call in the ISR
> when no fences remain.
> 
> Measured syncpoint wait latency (50000 samples):
>   Average latency:   12.2 us  -> 9.4 us
>   99.99 pct latency: 62.96 us -> 36.58 us
> 
> Tanmay Patil (2):
>   gpu: host1x: skip redundant syncpoint loads in host1x_syncpt_wait()
>   gpu: host1x: skip redundant HW state update
> 
>  drivers/gpu/host1x/intr.c   |  8 ++++++--
>  drivers/gpu/host1x/syncpt.c | 23 ++++++++++++++---------
>  2 files changed, 20 insertions(+), 11 deletions(-)
> 
> -- 
> 2.54.0
> 
> 

Thank you!

Acked-by: Mikko Perttunen <mperttunen@nvidia.com>