Replace SNDRV_DMA_TYPE_DEV by SNDRV_DMA_TYPE_NONCOHERENT for pcm
buffer allocation. We measured about 18x performance improvement
when accessing the snd_pcm_mmap() buffer from userspace.
Eg: aarch64 with internal speaker
==
SNDRV_DMA_TYPE_DEV
frames_per_second=66.4557M/s
max_time_per_4096_frames=106.094u
time_per_4096_frames=61.6351us
SNDRV_DMA_TYPE_NONCOHERENT
frames_per_second=1028.58M/s
max_time_per_4096_frames=20.312u
time_per_4096_frames=3.98221us
Signed-off-by: Judy Hsiao <[email protected]>
---
sound/soc/qcom/lpass-platform.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/soc/qcom/lpass-platform.c b/sound/soc/qcom/lpass-platform.c
index b41ab7a321ae..ef5cb40b2d9b 100644
--- a/sound/soc/qcom/lpass-platform.c
+++ b/sound/soc/qcom/lpass-platform.c
@@ -1181,7 +1181,7 @@ static int lpass_platform_pcm_new(struct snd_soc_component *component,
if (is_cdc_dma_port(dai_id))
return lpass_platform_prealloc_cdc_dma_buffer(component, pcm, dai_id);
- return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
+ return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_NONCOHERENT,
component->dev, size);
}
--
2.39.0.rc0.267.gcb52ba06e7-goog
On Thu, 08 Dec 2022 08:42:00 +0000, Judy Hsiao wrote:
> Replace SNDRV_DMA_TYPE_DEV by SNDRV_DMA_TYPE_NONCOHERENT for pcm
> buffer allocation. We measured about 18x performance improvement
> when accessing the snd_pcm_mmap() buffer from userspace.
>
> Eg: aarch64 with internal speaker
> ==
> SNDRV_DMA_TYPE_DEV
> frames_per_second=66.4557M/s
> max_time_per_4096_frames=106.094u
> time_per_4096_frames=61.6351us
>
> [...]
Applied to
broonie/sound.git for-next
Thanks!
[1/1] ASoC: qcom: lpass-platform: Use SNDRV_DMA_TYPE_NONCOHERENT page allocation
commit: 01270f905eea786f418cbc2040f7a52b969ef377
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
should be sent as incremental updates against current git, existing
patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying
to this mail.
Thanks,
Mark