ariff 2006-03-31 10:36:36 UTC
FreeBSD src repository
MEGA Fixes / Cleanup
- Seal the fate of long standing memory leak (4 years, 7 months) during
pcm_unregister(). While destroying cdevs, scan / detect possible
children and free its SLIST placeholder properly.
- Optimize channel allocation / numbering even further. Do brute cyclic
checking only if the channel numbering screwed.
- Mega vchan create/destroy cleanup:
o Implement pcm_setvchans() so everybody can use it freely instead
of implementing their own, be it through sysctl or channel auto
o Increase vchan creation/destruction resiliency:
+ it's possible to increase/decrease total vchans even during
busy playback/recording. Busy channel will be left alone, untouched.
Abusive test sample:
# play whatever...
while : ; do
# Play something else, leave above loop running frantically.
+ Seal another 4 years old bug where it is possible to destroy (virtual)
channel even when its cdevs being referenced by other process.
The "First Come First Served" nature of dsp_clone() is the main
culprit of this issue, and usually manifest itself as dangling
channel <-> process association. Ensure that all of its cdevs
are free from being referenced before destroying it (through
All these fixes (including previous fixes) will be MFCed, later.
Revision Changes Path
1.103 +239 -300 src/sys/dev/sound/pcm/sound.c