audio: copier: avoid IRQ lock/unlock in chmap code#10972
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Copier set_chmap() blocks IRQs to atomically update the converters. This code is not safe to be moved to user-space, so replace the locks with calls to block LL scheduler execution. Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
kv2019i
requested review from
jsarha,
lgirdwood,
lyakh,
serhiy-katsyuba-intel and
wjablon1
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Pull request overview
Updates the copier channel-map update path to avoid disabling/enabling IRQs when building with user-space LL scheduling, switching to the LL scheduler’s per-core lock for atomic updates of converter function pointers and channel maps.
Changes:
- Add LL scheduler domain header to access
user_ll_lock_sched()/user_ll_unlock_sched(). - Use LL scheduler locking in
set_chmap()underCONFIG_SOF_USERSPACE_LL, otherwise keep the IRQ disable/enable path.
| #include <rtos/interrupt.h> | ||
| #include <sof/ipc/msg.h> | ||
| #include <sof/ipc/topology.h> | ||
| #include <sof/schedule/ll_schedule_domain.h> | ||
| #include <rtos/interrupt.h> |
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Not part of this PR.
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For context, related to #10558 |
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| /* Atomically update chmap, process and converters */ | ||
| /* Atomically update chmap, process and converters. | ||
| * In user-space builds irq_local_disable() is privileged, |
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irq_local_disable() is privileged in all builds ;-)
| user_ll_lock_sched(dev->pipeline->core); | ||
| #else | ||
| irq_local_disable(irq_flags); | ||
| #endif |
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does it actually make sense to change the copier channel map while it's already processing data? If not, if this function should only run when there's no active streaming taking place, maybe we could just put a status check in the beginning of this function and avoid locking entirely?
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That channel-map functionality was added to support the posture feature. During playback, a user can rotate the tablet by 180 degrees, and the driver sends an IPC message with an updated channel map to switch the channels. This function is called from the IPC thread and can be preempted by an LL thread; hence, the lock.
Copier set_chmap() blocks IRQs to atomically update the converters. This code is not safe to be moved to user-space, so replace the locks with calls to block LL scheduler execution.