stack
Action
void stack(int nframes) void stack(void)
The stack
action records a kernel stack trace to the directed buffer. The kernel stack will be nframes in depth. If nframes is not provided, the number of stack frames recorded is the number specified by the stackframes
option. For example:
# dtrace -n uiomove:entry'{stack()}'
CPU ID FUNCTION:NAME
0 9153 uiomove:entry
genunix`fop_write+0x1b
namefs`nm_write+0x1d
genunix`fop_write+0x1b
genunix`write+0x1f7
0 9153 uiomove:entry
genunix`fop_read+0x1b
genunix`read+0x1d4
0 9153 uiomove:entry
genunix`strread+0x394
specfs`spec_read+0x65
genunix`fop_read+0x1b
genunix`read+0x1d4
...
The stack
action is a little different from other actions in that it may also be used as the key to an aggregation:
# dtrace -n kmem_alloc:entry'{@[stack()] = count()}'
dtrace: description 'kmem_alloc:entry' matched 1 probe
^C
rpcmod`endpnt_get+0x47c
rpcmod`clnt_clts_kcallit_addr+0x26f
rpcmod`clnt_clts_kcallit+0x22
nfs`rfscall+0x350
nfs`rfs2call+0x60
nfs`nfs_getattr_otw+0x9e
nfs`nfsgetattr+0x26
nfs`nfs_getattr+0xb8
genunix`fop_getattr+0x18
genunix`cstat64+0x30
genunix`cstatat64+0x4a
genunix`lstat64+0x1c
1
genunix`vfs_rlock_wait+0xc
genunix`lookuppnvp+0x19d
genunix`lookuppnat+0xe7
genunix`lookupnameat+0x87
genunix`lookupname+0x19
genunix`chdir+0x18
1
rpcmod`endpnt_get+0x6b1
rpcmod`clnt_clts_kcallit_addr+0x26f
rpcmod`clnt_clts_kcallit+0x22
nfs`rfscall+0x350
nfs`rfs2call+0x60
nfs`nfs_getattr_otw+0x9e
nfs`nfsgetattr+0x26
nfs`nfs_getattr+0xb8
genunix`fop_getattr+0x18
genunix`cstat64+0x30
genunix`cstatat64+0x4a
genunix`lstat64+0x1c
1
...