Macros

kadb(1M) supports macros that are used for displaying kernel data structures. kadb(1M) macros can be displayed with $M. Macros are used in the form:

    [ address ] $<macroname

threadlist is a useful macro that displays the stacks of all the threads in the system.

kadb[0]: $<threadlist

                ============== thread_id        10404000
p0+0x300:
                process args    sched

t0+0xa8:        lwp             procp           wchan
                1041b810        10424688        0
t0+0x24:
                pc              sp
                sched+0x4f4     10403be8
?(10404000,1040c000,2,10424604,0,6e)
_start(10006ef4,1041adb0,1041adb0,1041adb0,10462910,50) + 15c

...

                ============== thread_id        40043e60
p0+0x300:
                process args    sched

40043f08:       lwp             procp           wchan
                0               10424688        10473c56
40043e84:
                pc              sp
                cv_wait+0x60    40043c08
?(10473c56,10473c5c,0,40043cd0,40043e60,10093084)
ufs_thread_idle(10471e80,0,10473c5c,10424688,81010100,0) + bc
thread_start(0,0,0,0,0,0) + 4
...

Another useful macro is thread. Given a thread ID, this macro prints the corresponding thread structure. This can be used to look at a certain thread found with the threadlist macro, to look at the owner of a mutex, or to look at the current thread, as shown here:

kadb[0]: <g7$<thread
70e87ac0:       link            stk             startpc
                0               4026bc80        0
70e87acc:       bound_cpu       affinitycnt     bind_cpu
                0               0               -1
70e87ad4:       flag    proc_flag       schedflag
                0       4               3
70e87ada:       preempt preempt_lk      state
                0       0               4
70e87ae0:       pri     epri
                40      0
70e87ae4:
                pc              sp
                10098350        4026b618
70e87aec:       wchan0          wchan           sobj_ops
                0               0               0
70e87af8:       cid             clfuncs         cldata
                1               10470ffc        702c0488
70e87b04:       ctx             lofault         onfault
                0               0               0
...

No type information is kept in the kernel, so using a macro on an inappropriate address results in garbage output.

Macros do not necessarily output all the fields of the structures, nor is the output necessarily in the order given in the structure definition. Occasionally, memory needs to be dumped for certain structures and then matched with the structure definition in the kernel header files.

Drivers should never reference header files and structures not listed in man pages section 9S: DDI and DKI Data Structures. However, examining non-DDI-compliant structures (such as thread structures) can be useful in debugging drivers.