@@ -1751,13 +1751,8 @@ unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
// Later, the process context will sometimes schedules software
// IRQ context of the period_work. Then, no need to flush the
// queue by the same reason as described in the above
- if (current_work() != &s->period_work) {
- // Queued packet should be processed without any kernel
- // preemption to keep latency against bus cycle.
- preempt_disable();
+ if (current_work() != &s->period_work)
fw_iso_context_flush_completions(irq_target->context);
- preempt_enable();
- }
}
return READ_ONCE(s->pcm_buffer_pointer);
@@ -1777,13 +1772,8 @@ int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s)
// Process isochronous packets for recent isochronous cycle to handle
// queued PCM frames.
- if (irq_target && amdtp_stream_running(irq_target)) {
- // Queued packet should be processed without any kernel
- // preemption to keep latency against bus cycle.
- preempt_disable();
+ if (irq_target && amdtp_stream_running(irq_target))
fw_iso_context_flush_completions(irq_target->context);
- preempt_enable();
- }
return 0;
}
In all of drivers of ALSA firewire stack, the callback of .pointer and .ack in snd_pcm_ops structure is done in acquired spin_lock of PCM substream, therefore already under disabled kernel preemption. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> --- sound/firewire/amdtp-stream.c | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-)