proc lwpsinfo_t Structure

Several proc probes have arguments of type lwpsinfo_t. The definition of the lwpsinfo_t structure as available to DTrace consumers is as follows:

typedef struct lwpsinfo {
        int pr_flag;              /* flags; see below */
        id_t pr_lwpid;            /* LWP id */
        uintptr_t pr_addr;        /* internal address of thread */
        uintptr_t pr_wchan;       /* wait addr for sleeping thread */
        char pr_stype;            /* synchronization event type */
        char pr_state;            /* numeric thread state */
        char pr_sname;            /* printable character for pr_state */
        char pr_nice;             /* nice for cpu usage */
        short pr_syscall;         /* system call number (if in syscall) */
        int pr_pri;               /* priority, high value = high priority */
        char pr_clname[PRCLSZ];   /* scheduling class name */
        processorid_t pr_onpro;   /* processor which last ran this thread */
        processorid_t pr_bindpro; /* processor to which thread is bound */
        psetid_t pr_bindpset;     /* processor set to which thread is bound */
} lwpsinfo_t;

The pr_flag field is a bit-mask holding flags describing the process. These flags and their meanings are described in Table 11-25.

Table 11-25 proc pr_flag Values

Flags	Descriptions
PR_ISSYS	The process is a system process.
PR_VFORKP	The process is the parent of a vfork child.
PR_FORK	The process has its inherit-on-fork mode set.
PR_RLC	The process has its run-on-last-close mode set.
PR_KLC	The process has its kill-on-last-close mode set.
PR_ASYNC	The process has its asynchronous-stop mode set.
PR_MSACCT	The process has microstate accounting enabled.
PR_MSFORK	The process microstate accounting is inherited on fork.
PR_BPTADJ	The process has its breakpoint adjustment mode set.
PR_PTRACE	The process has its ptrace compatibility mode set.
PR_STOPPED	The thread is an LWP that is stopped.
PR_ISTOP	The thread is an LWP stopped on an event of interest.
PR_DSTOP	The thread is an LWP that has a stop directive in effect.
PR_STEP	The thread is an LWP that has a single-step directive in effect.
PR_ASLEEP	The thread is an LWP in an interruptible sleep within a system call.
PR_DETACH	The thread is a detached LWP. See the pthread_create(3C) and pthread_join(3C) man pages.
PR_DAEMON	The thread is a daemon LWP. See the pthread_create() function.
PR_AGENT	The thread is the agent LWP for the process.
PR_IDLE	The thread is the idle thread for a CPU. Idle threads only run on a CPU when the run queues for the CPU are empty.

The pr_addr field is the address of a private, in-kernel data structure representing the thread. While the data structure is private, the pr_addr field may be used as a token unique to a thread for the thread's lifetime.

The pr_wchan field is set when the thread is sleeping on a synchronization object. The meaning of the pr_wchan field is private to the kernel implementation, but the field may be used as a token unique to the synchronization object.

The pr_stype field is set when the thread is sleeping on a synchronization object. The following table describes the possible values for the pr_stype field.

Table 11-26 proc pr_stype Values

Value	Description
SOBJ_MUTEX	Kernel mutex synchronization object. Used to serialize access to shared data regions in the kernel. For more information about kernel mutex synchronization objects, see lockstat Stability and the mutex_init(9F) man page.
SOBJ_RWLOCK	Kernel readers/writer synchronization object. Used to synchronize access to shared objects in the kernel that can allow multiple concurrent readers or a single writer. For more information about kernel readers/writer synchronization objects, see lockstat Stability and the rwlock(9F) man page.
SOBJ_CV	Condition variable synchronization object. A condition variable is designed to wait indefinitely until some condition becomes true. Condition variables are typically used to synchronize for reasons other than access to a shared data region, and are the mechanism generally used when a process performs a program-directed indefinite wait. For example, blocking in poll, pause, wait, and the like.
SOBJ_SEMA	Semaphore synchronization object. A general-purpose synchronization object that – like condition variable objects – does not track a notion of ownership. Because ownership is required to implement priority inheritance in the Oracle Solaris kernel, the lack of ownership inherent in semaphore objects inhibits their widespread use. See the semaphore(9F) man page for details.
SOBJ_USER	A user-level synchronization object. All blocking on user-level synchronization objects is handled with SOBJ_USER synchronization objects. User-level synchronization objects include those created with mutex_init(), sema_init(), rwlock_init(), cond_init() and their POSIX equivalents.
SOBJ_USER_PI	A user-level synchronization object that implements priority inheritance. Some user-level synchronization objects that track ownership additionally allow for priority inheritance. For example, mutex objects created with pthread_mutex_init() may be made to inherit priority using pthread_mutexattr_setprotocol().
SOBJ_SHUTTLE	A shuttle synchronization object. Shuttle objects are used to implement doors. See door_create(3DOOR)() for more information.

The pr_state field is set to one of the values in Table 11-27. The pr_sname field is set to a corresponding character shown in parentheses in the same table.

Table 11-27 proc pr_state Values

Value	Description
SSLEEP (S)	The thread is sleeping. The sched:::sleep probe will fire immediately before a thread's state is transitioned to SSLEEP.
SRUN (R)	The thread is runnable, but is not currently running. The sched:::enqueue probe will fire immediately before a thread's state is transitioned to SRUN.
SZOMB (Z)	The thread is a zombie LWP.
SSTOP (T)	The thread is stopped, either due to an explicit proc directive or some other stopping mechanism.
SIDL (I)	The thread is an intermediate state during process creation.
SONPROC (O)	The thread is running on a CPU. The sched:::on-cpu probe will fire in the context of the SONPROC thread a short time after the thread's state is transitioned to SONPROC.
SWAIT (W)	The thread is waiting on wait queue. The sched:::cpucaps-sleep probe will fire immediately before a thread state is transitioned to SWAIT.