Re: pcm & exclusive sleep mutex with Oct19 CURRENT

On Mon, Oct 20, 2003 at 10:37:00AM -0700, Kris Kennaway wrote:
> Unfortunately none of the sound developers have been interested in
> looking at the locking problems in the code.

=(
 
> > acquiring duplicate lock of same type: "pcm channel"
> >  1st pcm0:record:0 _at_ /usr/src/sys/dev/sound/pcm/sound.c:195
> >  2nd pcm0:play:0 _at_ /usr/src/sys/dev/sound/pcm/sound.c:195
> > Stack backtrace:
> > 
> > with no backtrace at all.
> 
> FWIW, the backtrace would have been reported on the system console.

righty right kris, here we go:

backtrace(c0836d0c,c2d41754,c0a257d1,c3,246) at backtrace+0x17
witness_lock(c2d347c0,8,c0a257d1,c3,c2d34500) at witness_lock+0x672
_mtx_lock_flags(c2d347c0,0,c0a257d1,c3,3) at _mtx_lock_flags+0xba
pcm_chnalloc(c2d1f400,1,9e7c,ffffffff,8) at pcm_chnalloc+0x56
dsp_open(c08f10f0,803,2000,c340d130,c06947a2) at dsp_open+0x19f
spec_open(cf175a68,cf175b24,c069c6b2,cf175a68,0) at spec_open+0x30b
spec_vnoperate(cf175a68,0,c08fe0e0,c340d130,c392b248) at spec_vnoperate+0x18
vn_open_cred(cf175bd8,cf175cd8,0,c3ef6880,20) at vn_open_cred+0x432
vn_open(cf175bd8,cf175cd8,0,20,c08f7b30) at vn_open+0x30
kern_open(c340d130,8ae2050,0,803,0) at kern_open+0x140
open(c340d130,cf175d10,c084f404,3ed,3) at open+0x30
syscall(1002f,893002f,bfbf002f,29a975b5,8ae2058) at syscall+0x2c0
Xint0x80_syscall() at Xint0x80_syscall+0x1d
--- syscall (5), eip = 0x2853ed3f, esp = 0xbfbfb4fc, ebp = 0xbfbfb518 ---

and 

backtrace(c0836dc3,c102f110,c08497be,c08497be,c0849659) at backtrace+0x17
witness_lock(c102f110,8,c0849659,148,0) at witness_lock+0x672
_mtx_lock_flags(c102f110,0,c0849659,148,3) at _mtx_lock_flags+0xba
_vm_map_lock(c102f0b0,c0849659,148,c08f5de0,2b4) at _vm_map_lock+0x36
kmem_malloc(c102f0b0,1000,101,ce70a810,c07996f7) at kmem_malloc+0x3a
page_alloc(c103a3c0,1000,ce70a803,101,c083326a) at page_alloc+0x27
slab_zalloc(c103a3c0,1,8,c084afa2,68c) at slab_zalloc+0xb7
uma_zone_slab(c103a3c0,1,c084afa2,68c,0) at uma_zone_slab+0xe6
uma_zalloc_internal(c103a3c0,0,1,0,c101f470) at uma_zalloc_internal+0x3e
bucket_alloc(44,1,c084afa2,70b,0) at bucket_alloc+0x5e
uma_zfree_arg(c101f3c0,ce77ae04,0,778,0) at uma_zfree_arg+0x2c6
swp_pager_meta_free_all(c30e5cb8,c0848f76,c0848edb,21a) at swp_pager_meta_free_a
ll+0xf2
swap_pager_dealloc(c30e5cb8,1,c084af06,104,0) at swap_pager_dealloc+0x11a
vm_pager_deallocate(c30e5cb8,0,c084a0eb,260,c084afa2) at vm_pager_deallocate+0x3
d
vm_object_terminate(c30e5cb8,0,c084a0eb,207,c062d650) at vm_object_terminate+0x2
03
vm_object_deallocate(c30e5cb8,c2ee8d98,c30e5cb8,c2ee8d98,ce70a9c8) at vm_object_
deallocate+0x371
vm_map_entry_delete(c16d59d8,c2ee8d98,c0849834,8b6,0) at vm_map_entry_delete+0x3
b
vm_map_delete(c16d59d8,0,bfc00000,c16d59d8,c16d59d8) at vm_map_delete+0x383
vm_map_remove(c16d59d8,0,bfc00000,356,804f2c4) at vm_map_remove+0x55
exec_new_vmspace(ce70ab88,c08c7ac0,c0830c69,296,0) at exec_new_vmspace+0x235
exec_elf32_imgact(ce70ab88,0,c08318b5,ff,c08f77e8) at exec_elf32_imgact+0x1b0
kern_execve(c2d38980,8051080,bfbffd1c,804f2c0,0) at kern_execve+0x38c
execve(c2d38980,ce70ad10,c084f404,3ed,3) at execve+0x30
syscall(2f,2f,2f,1,bfbffd1c) at syscall+0x2c0
Xint0x80_syscall() at Xint0x80_syscall+0x1d
--- syscall (59), eip = 0x280d683f, esp = 0xbfbffd0c, ebp = 0xbfbffd38 ---

hope this helps.

-- 
Paolo

Italian FreeBSD User Group: http://www.gufi.org