[BUG] PCM probe does not work with multicore topologies

[kv2019i]

Describe the bug The pcm probe client uses notifier_register() to register to buffers (to probe). The notifier interface registers the notifier just for the calling CPU and if the buffer is attached to a pipeline running on a different core, no notifications are received and thus no data is probed.

To Reproduce Use a multicore pipeline like cavs-nocodec. Start playback with pipeline assigned to non-zero core, attach probe points to buffers of this pipeline.

Reproduction Rate 100%

Expected behavior Probe interface works for all buffers independently of the core they are allocated to.

Impact Unable to use PCM probe to debug issues with multicore topologies.

Environment

1. Branch name and commit hash of the 2 repositories: sof (firmware/topology) and linux (kernel driver).
   • Kernel: n/a
   • SOF: 9d37a33335d4a68e0433f6bca6cb5739b06500d5
2. Name of the topology file
   • Topology: sof-tgl-nocodec.tplg
3. Name of the platform(s) on which the bug is observed.
   • Platform: Intel TGL

Screenshots or console output

[lgirdwood]

@kv2019i xtos or zephy ?

[kv2019i]

@lgirdwood wrote:

@kv2019i xtos or zephy ?

Both.

[lyakh]

probes don't acquire buffers correctly, let me try to cook up a patch

[kv2019i]

Discussion about how to fix this: https://github.com/thesofproject/sof/pull/6137#discussion_r945478298