sys/dev/sound/pcm/sndstat.c:

• General spl* cleanup. It doesn't serve any purpose anymore.
• Nuke sndstat_busy(). Addition of sndstat_acquire() / sndstat_release() for sndstat exclusive access. [1]

sys/dev/sound/pcm/sound.c:

• Remove duplicate SLIST_INIT()
• Use sndstat_acquire() / release() to lock / release the entire sndstat during pcm_unregister(). This should fix LOR #159 [1]

sys/dev/sound/pcm/sound.h:

• Definition of SD_F_SOFTVOL (part of feeder volume)
• Nuke sndstat_busy(). Addition of sndstat_acquire() / sndstat_release() for exclusive sndstat access. [1]

Submitted by: Ariff Abdullah <skywizard@MyBSD.org.my>
LOR: 159 [1]
Discussed with: yongari [1]