8158 Want named threads API

[unleashed.git] / usr / src / uts / common / sys / thread.h

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright 2018 Joyent, Inc.
 */

#ifndef _SYS_THREAD_H
#define _SYS_THREAD_H


#include <sys/types.h>
#include <sys/t_lock.h>
#include <sys/klwp.h>
#include <sys/time.h>
#include <sys/signal.h>
#include <sys/kcpc.h>
#if defined(__GNUC__) && defined(_ASM_INLINES) && defined(_KERNEL)
#include <asm/thread.h>
#endif

#ifdef  __cplusplus
extern "C" {
#endif

/*
 * The thread object, its states, and the methods by which it
 * is accessed.
 */

/*
 * Values that t_state may assume. Note that t_state cannot have more
 * than one of these flags set at a time.
 */
#define TS_FREE         0x00    /* Thread at loose ends */
#define TS_SLEEP        0x01    /* Awaiting an event */
#define TS_RUN          0x02    /* Runnable, but not yet on a processor */
#define TS_ONPROC       0x04    /* Thread is being run on a processor */
#define TS_ZOMB         0x08    /* Thread has died but hasn't been reaped */
#define TS_STOPPED      0x10    /* Stopped, initial state */
#define TS_WAIT         0x20    /* Waiting to become runnable */

typedef struct ctxop {
        void    (*save_op)(void *);     /* function to invoke to save context */
        void    (*restore_op)(void *);  /* function to invoke to restore ctx */
        void    (*fork_op)(void *, void *);     /* invoke to fork context */
        void    (*lwp_create_op)(void *, void *);       /* lwp_create context */
        void    (*exit_op)(void *);     /* invoked during {thread,lwp}_exit() */
        void    (*free_op)(void *, int); /* function which frees the context */
        void    *arg;           /* argument to above functions, ctx pointer */
        struct ctxop *next;     /* next context ops */
} ctxop_t;

/*
 * The active file descriptor table.
 * Each member of a_fd[] not equalling -1 represents an active fd.
 * The structure is initialized on first use; all zeros means uninitialized.
 */
typedef struct {
        kmutex_t a_fdlock;      /* protects a_fd and a_nfd */
        int     *a_fd;          /* pointer to list of fds */
        int     a_nfd;          /* number of entries in *a_fd */
        int     a_stale;        /* one of the active fds is being closed */
        int     a_buf[2];       /* buffer to which a_fd initially refers */
} afd_t;

/*
 * An lwpchan provides uniqueness when sleeping on user-level
 * synchronization primitives.  The lc_wchan member is used
 * for sleeping on kernel synchronization primitives.
 */
typedef struct {
        caddr_t lc_wchan0;
        caddr_t lc_wchan;
} lwpchan_t;

typedef struct _kthread *kthread_id_t;

struct turnstile;
struct panic_trap_info;
struct upimutex;
struct kproject;
struct on_trap_data;
struct waitq;
struct _kcpc_ctx;
struct _kcpc_set;

/* Definition for kernel thread identifier type */
typedef uint64_t kt_did_t;

typedef struct _kthread {
        struct _kthread *t_link; /* dispq, sleepq, and free queue link */

        caddr_t t_stk;          /* base of stack (kernel sp value to use) */
        void    (*t_startpc)(void);     /* PC where thread started */
        struct cpu *t_bound_cpu; /* cpu bound to, or NULL if not bound */
        short   t_affinitycnt;  /* nesting level of kernel affinity-setting */
        short   t_bind_cpu;     /* user-specified CPU binding (-1 if none) */
        ushort_t t_flag;                /* modified only by current thread */
        ushort_t t_proc_flag;   /* modified holding ttproc(t)->p_lock */
        ushort_t t_schedflag;   /* modified holding thread_lock(t) */
        volatile char t_preempt;        /* don't preempt thread if set */
        volatile char t_preempt_lk;
        uint_t  t_state;        /* thread state (protected by thread_lock) */
        pri_t   t_pri;          /* assigned thread priority */
        pri_t   t_epri;         /* inherited thread priority */
        pri_t   t_cpri;         /* thread scheduling class priority */
        char    t_writer;       /* sleeping in lwp_rwlock_lock(RW_WRITE_LOCK) */
        uchar_t t_bindflag;     /* CPU and pset binding type */
        label_t t_pcb;          /* pcb, save area when switching */
        lwpchan_t t_lwpchan;    /* reason for blocking */
#define t_wchan0        t_lwpchan.lc_wchan0
#define t_wchan         t_lwpchan.lc_wchan
        struct _sobj_ops *t_sobj_ops;
        id_t    t_cid;          /* scheduling class id */
        struct thread_ops *t_clfuncs;   /* scheduling class ops vector */
        void    *t_cldata;      /* per scheduling class specific data */
        ctxop_t *t_ctx;         /* thread context */
        uintptr_t t_lofault;    /* ret pc for failed page faults */
        label_t *t_onfault;     /* on_fault() setjmp buf */
        struct on_trap_data *t_ontrap;  /* on_trap() protection data */
        caddr_t t_swap;         /* the bottom of the stack, if from segkp */
        lock_t  t_lock;         /* used to resume() a thread */
        uint8_t t_lockstat;     /* set while thread is in lockstat code */
        uint8_t t_pil;          /* interrupt thread PIL */
        disp_lock_t     t_pi_lock;      /* lock protecting t_prioinv list */
        char    t_nomigrate;    /* do not migrate if set */
        struct cpu      *t_cpu; /* CPU that thread last ran on */
        struct cpu      *t_weakbound_cpu;       /* cpu weakly bound to */
        struct lgrp_ld  *t_lpl; /* load average for home lgroup */
        void            *t_lgrp_reserv[2];      /* reserved for future */
        struct _kthread *t_intr; /* interrupted (pinned) thread */
        uint64_t        t_intr_start;   /* timestamp when time slice began */
        kt_did_t        t_did;  /* thread id for kernel debuggers */
        caddr_t t_tnf_tpdp;     /* Trace facility data pointer */
        struct _kcpc_ctx *t_cpc_ctx;    /* performance counter context */
        struct _kcpc_set *t_cpc_set;    /* set this thread has bound */

        /*
         * non swappable part of the lwp state.
         */
        id_t            t_tid;          /* lwp's id */
        id_t            t_waitfor;      /* target lwp id in lwp_wait() */
        struct sigqueue *t_sigqueue;    /* queue of siginfo structs */
        k_sigset_t      t_sig;          /* signals pending to this process */
        k_sigset_t      t_extsig;       /* signals sent from another contract */
        k_sigset_t      t_hold;         /* hold signal bit mask */
        k_sigset_t      t_sigwait;      /* sigtimedwait/sigfd accepting these */
        struct  _kthread *t_forw;       /* process's forward thread link */
        struct  _kthread *t_back;       /* process's backward thread link */
        struct  _kthread *t_thlink;     /* tid (lwpid) lookup hash link */
        klwp_t  *t_lwp;                 /* thread's lwp pointer */
        struct  proc    *t_procp;       /* proc pointer */
        struct  t_audit_data *t_audit_data;     /* per thread audit data */
        struct  _kthread *t_next;       /* doubly linked list of all threads */
        struct  _kthread *t_prev;
        ushort_t t_whystop;             /* reason for stopping */
        ushort_t t_whatstop;            /* more detailed reason */
        int     t_dslot;                /* index in proc's thread directory */
        struct  pollstate *t_pollstate; /* state used during poll(2) */
        struct  pollcache *t_pollcache; /* to pass a pcache ptr by /dev/poll */
        struct  cred    *t_cred;        /* pointer to current cred */
        time_t  t_start;                /* start time, seconds since epoch */
        clock_t t_lbolt;                /* lbolt at last clock_tick() */
        hrtime_t t_stoptime;            /* timestamp at stop() */
        uint_t  t_pctcpu;               /* %cpu at last clock_tick(), binary */
                                        /* point at right of high-order bit */
        short   t_sysnum;               /* system call number */
        kcondvar_t      t_delay_cv;
        kmutex_t        t_delay_lock;

        /*
         * Pointer to the dispatcher lock protecting t_state and state-related
         * flags.  This pointer can change during waits on the lock, so
         * it should be grabbed only by thread_lock().
         */
        disp_lock_t     *t_lockp;       /* pointer to the dispatcher lock */
        ushort_t        t_oldspl;       /* spl level before dispatcher locked */
        volatile char   t_pre_sys;      /* pre-syscall work needed */
        lock_t          t_lock_flush;   /* for lock_mutex_flush() impl */
        struct _disp    *t_disp_queue;  /* run queue for chosen CPU */
        clock_t         t_disp_time;    /* last time this thread was running */
        uint_t          t_kpri_req;     /* kernel priority required */

        /*
         * Post-syscall / post-trap flags.
         *      No lock is required to set these.
         *      These must be cleared only by the thread itself.
         *
         *      t_astflag indicates that some post-trap processing is required,
         *              possibly a signal or a preemption.  The thread will not
         *              return to user with this set.
         *      t_post_sys indicates that some unusualy post-system call
         *              handling is required, such as an error or tracing.
         *      t_sig_check indicates that some condition in ISSIG() must be
         *              checked, but doesn't prevent returning to user.
         *      t_post_sys_ast is a way of checking whether any of these three
         *              flags are set.
         */
        union __tu {
                struct __ts {
                        volatile char   _t_astflag;     /* AST requested */
                        volatile char   _t_sig_check;   /* ISSIG required */
                        volatile char   _t_post_sys;    /* post_syscall req */
                        volatile char   _t_trapret;     /* call CL_TRAPRET */
                } _ts;
                volatile int    _t_post_sys_ast;        /* OR of these flags */
        } _tu;
#define t_astflag       _tu._ts._t_astflag
#define t_sig_check     _tu._ts._t_sig_check
#define t_post_sys      _tu._ts._t_post_sys
#define t_trapret       _tu._ts._t_trapret
#define t_post_sys_ast  _tu._t_post_sys_ast

        /*
         * Real time microstate profiling.
         */
                                        /* possible 4-byte filler */
        hrtime_t t_waitrq;              /* timestamp for run queue wait time */
        int     t_mstate;               /* current microstate */
        struct rprof {
                int     rp_anystate;            /* set if any state non-zero */
                uint_t  rp_state[NMSTATES];     /* mstate profiling counts */
        } *t_rprof;

        /*
         * There is a turnstile inserted into the list below for
         * every priority inverted synchronization object that
         * this thread holds.
         */

        struct turnstile *t_prioinv;

        /*
         * Pointer to the turnstile attached to the synchronization
         * object where this thread is blocked.
         */

        struct turnstile *t_ts;

        /*
         * kernel thread specific data
         *      Borrowed from userland implementation of POSIX tsd
         */
        struct tsd_thread {
                struct tsd_thread *ts_next;     /* threads with TSD */
                struct tsd_thread *ts_prev;     /* threads with TSD */
                uint_t            ts_nkeys;     /* entries in value array */
                void              **ts_value;   /* array of value/key */
        } *t_tsd;

        clock_t         t_stime;        /* time stamp used by the swapper */
        struct door_data *t_door;       /* door invocation data */
        kmutex_t        *t_plockp;      /* pointer to process's p_lock */

        struct sc_shared *t_schedctl;   /* scheduler activations shared data */
        uintptr_t       t_sc_uaddr;     /* user-level address of shared data */

        struct cpupart  *t_cpupart;     /* partition containing thread */
        int             t_bind_pset;    /* processor set binding */

        struct copyops  *t_copyops;     /* copy in/out ops vector */

        caddr_t         t_stkbase;      /* base of the the stack */
        struct page     *t_red_pp;      /* if non-NULL, redzone is mapped */

        afd_t           t_activefd;     /* active file descriptor table */

        struct _kthread *t_priforw;     /* sleepq per-priority sublist */
        struct _kthread *t_priback;

        struct sleepq   *t_sleepq;      /* sleep queue thread is waiting on */
        struct panic_trap_info *t_panic_trap;   /* saved data from fatal trap */
        int             *t_lgrp_affinity;       /* lgroup affinity */
        struct upimutex *t_upimutex;    /* list of upimutexes owned by thread */
        uint32_t        t_nupinest;     /* number of nested held upi mutexes */
        struct kproject *t_proj;        /* project containing this thread */
        uint8_t         t_unpark;       /* modified holding t_delay_lock */
        uint8_t         t_release;      /* lwp_release() waked up the thread */
        uint8_t         t_hatdepth;     /* depth of recursive hat_memloads */
        uint8_t         t_xpvcntr;      /* see xen_block_migrate() */
        kcondvar_t      t_joincv;       /* cv used to wait for thread exit */
        void            *t_taskq;       /* for threads belonging to taskq */
        hrtime_t        t_anttime;      /* most recent time anticipatory load */
                                        /*      was added to an lgroup's load */
                                        /*      on this thread's behalf */
        char            *t_pdmsg;       /* privilege debugging message */

        uint_t          t_predcache;    /* DTrace predicate cache */
        hrtime_t        t_dtrace_vtime; /* DTrace virtual time */
        hrtime_t        t_dtrace_start; /* DTrace slice start time */

        uint8_t         t_dtrace_stop;  /* indicates a DTrace-desired stop */
        uint8_t         t_dtrace_sig;   /* signal sent via DTrace's raise() */

        union __tdu {
                struct __tds {
                        uint8_t _t_dtrace_on;   /* hit a fasttrap tracepoint */
                        uint8_t _t_dtrace_step; /* about to return to kernel */
                        uint8_t _t_dtrace_ret;  /* handling a return probe */
                        uint8_t _t_dtrace_ast;  /* saved ast flag */
#ifdef __amd64
                        uint8_t _t_dtrace_reg;  /* modified register */
#endif
                } _tds;
                ulong_t _t_dtrace_ft;           /* bitwise or of these flags */
        } _tdu;
#define t_dtrace_ft     _tdu._t_dtrace_ft
#define t_dtrace_on     _tdu._tds._t_dtrace_on
#define t_dtrace_step   _tdu._tds._t_dtrace_step
#define t_dtrace_ret    _tdu._tds._t_dtrace_ret
#define t_dtrace_ast    _tdu._tds._t_dtrace_ast
#ifdef __amd64
#define t_dtrace_reg    _tdu._tds._t_dtrace_reg
#endif

        uintptr_t       t_dtrace_pc;    /* DTrace saved pc from fasttrap */
        uintptr_t       t_dtrace_npc;   /* DTrace next pc from fasttrap */
        uintptr_t       t_dtrace_scrpc; /* DTrace per-thread scratch location */
        uintptr_t       t_dtrace_astpc; /* DTrace return sequence location */
#ifdef __amd64
        uint64_t        t_dtrace_regv;  /* DTrace saved reg from fasttrap */
        uint64_t        t_useracc;      /* SMAP state saved across swtch() */
#endif
        hrtime_t        t_hrtime;       /* high-res last time on cpu */
        kmutex_t        t_ctx_lock;     /* protects t_ctx in removectx() */
        struct waitq    *t_waitq;       /* wait queue */
        kmutex_t        t_wait_mutex;   /* used in CV wait functions */

        char            *t_name;        /* thread name */
} kthread_t;

/*
 * Thread flag (t_flag) definitions.
 *      These flags must be changed only for the current thread,
 *      and not during preemption code, since the code being
 *      preempted could be modifying the flags.
 *
 *      For the most part these flags do not need locking.
 *      The following flags will only be changed while the thread_lock is held,
 *      to give assurrance that they are consistent with t_state:
 *              T_WAKEABLE
 */
#define T_INTR_THREAD   0x0001  /* thread is an interrupt thread */
#define T_WAKEABLE      0x0002  /* thread is blocked, signals enabled */
#define T_TOMASK        0x0004  /* use lwp_sigoldmask on return from signal */
#define T_TALLOCSTK     0x0008  /* thread structure allocated from stk */
#define T_FORKALL       0x0010  /* thread was cloned by forkall() */
#define T_WOULDBLOCK    0x0020  /* for lockfs */
#define T_DONTBLOCK     0x0040  /* for lockfs */
#define T_DONTPEND      0x0080  /* for lockfs */
#define T_SYS_PROF      0x0100  /* profiling on for duration of system call */
#define T_WAITCVSEM     0x0200  /* waiting for a lwp_cv or lwp_sema on sleepq */
#define T_WATCHPT       0x0400  /* thread undergoing a watchpoint emulation */
#define T_PANIC         0x0800  /* thread initiated a system panic */
#define T_LWPREUSE      0x1000  /* stack and LWP can be reused */
#define T_CAPTURING     0x2000  /* thread is in page capture logic */
#define T_VFPARENT      0x4000  /* thread is vfork parent, must call vfwait */
#define T_DONTDTRACE    0x8000  /* disable DTrace probes */

/*
 * Flags in t_proc_flag.
 *      These flags must be modified only when holding the p_lock
 *      for the associated process.
 */
#define TP_DAEMON       0x0001  /* this is an LWP_DAEMON lwp */
#define TP_HOLDLWP      0x0002  /* hold thread's lwp */
#define TP_TWAIT        0x0004  /* wait to be freed by lwp_wait() */
#define TP_LWPEXIT      0x0008  /* lwp has exited */
#define TP_PRSTOP       0x0010  /* thread is being stopped via /proc */
#define TP_CHKPT        0x0020  /* thread is being stopped via CPR checkpoint */
#define TP_EXITLWP      0x0040  /* terminate this lwp */
#define TP_PRVSTOP      0x0080  /* thread is virtually stopped via /proc */
#define TP_MSACCT       0x0100  /* collect micro-state accounting information */
#define TP_STOPPING     0x0200  /* thread is executing stop() */
#define TP_WATCHPT      0x0400  /* process has watchpoints in effect */
#define TP_PAUSE        0x0800  /* process is being stopped via pauselwps() */
#define TP_CHANGEBIND   0x1000  /* thread has a new cpu/cpupart binding */
#define TP_ZTHREAD      0x2000  /* this is a kernel thread for a zone */
#define TP_WATCHSTOP    0x4000  /* thread is stopping via holdwatch() */

/*
 * Thread scheduler flag (t_schedflag) definitions.
 *      The thread must be locked via thread_lock() or equiv. to change these.
 */
#define TS_LOAD         0x0001  /* thread is in memory */
#define TS_DONT_SWAP    0x0002  /* thread/lwp should not be swapped */
#define TS_SWAPENQ      0x0004  /* swap thread when it reaches a safe point */
#define TS_ON_SWAPQ     0x0008  /* thread is on the swap queue */
#define TS_SIGNALLED    0x0010  /* thread was awakened by cv_signal() */
#define TS_PROJWAITQ    0x0020  /* thread is on its project's waitq */
#define TS_ZONEWAITQ    0x0040  /* thread is on its zone's waitq */
#define TS_CSTART       0x0100  /* setrun() by continuelwps() */
#define TS_UNPAUSE      0x0200  /* setrun() by unpauselwps() */
#define TS_XSTART       0x0400  /* setrun() by SIGCONT */
#define TS_PSTART       0x0800  /* setrun() by /proc */
#define TS_RESUME       0x1000  /* setrun() by CPR resume process */
#define TS_CREATE       0x2000  /* setrun() by syslwp_create() */
#define TS_RUNQMATCH    0x4000  /* exact run queue balancing by setbackdq() */
#define TS_ALLSTART     \
        (TS_CSTART|TS_UNPAUSE|TS_XSTART|TS_PSTART|TS_RESUME|TS_CREATE)
#define TS_ANYWAITQ     (TS_PROJWAITQ|TS_ZONEWAITQ)

/*
 * Thread binding types
 */
#define TB_ALLHARD      0
#define TB_CPU_SOFT     0x01            /* soft binding to CPU */
#define TB_PSET_SOFT    0x02            /* soft binding to pset */

#define TB_CPU_SOFT_SET(t)              ((t)->t_bindflag |= TB_CPU_SOFT)
#define TB_CPU_HARD_SET(t)              ((t)->t_bindflag &= ~TB_CPU_SOFT)
#define TB_PSET_SOFT_SET(t)             ((t)->t_bindflag |= TB_PSET_SOFT)
#define TB_PSET_HARD_SET(t)             ((t)->t_bindflag &= ~TB_PSET_SOFT)
#define TB_CPU_IS_SOFT(t)               ((t)->t_bindflag & TB_CPU_SOFT)
#define TB_CPU_IS_HARD(t)               (!TB_CPU_IS_SOFT(t))
#define TB_PSET_IS_SOFT(t)              ((t)->t_bindflag & TB_PSET_SOFT)

/*
 * No locking needed for AST field.
 */
#define aston(t)                ((t)->t_astflag = 1)
#define astoff(t)               ((t)->t_astflag = 0)

/* True if thread is stopped on an event of interest */
#define ISTOPPED(t) ((t)->t_state == TS_STOPPED && \
                        !((t)->t_schedflag & TS_PSTART))

/* True if thread is asleep and wakeable */
#define ISWAKEABLE(t) (((t)->t_state == TS_SLEEP && \
                        ((t)->t_flag & T_WAKEABLE)))

/* True if thread is on the wait queue */
#define ISWAITING(t) ((t)->t_state == TS_WAIT)

/* similar to ISTOPPED except the event of interest is CPR */
#define CPR_ISTOPPED(t) ((t)->t_state == TS_STOPPED && \
                        !((t)->t_schedflag & TS_RESUME))

/*
 * True if thread is virtually stopped (is or was asleep in
 * one of the lwp_*() system calls and marked to stop by /proc.)
 */
#define VSTOPPED(t)     ((t)->t_proc_flag & TP_PRVSTOP)

/* similar to VSTOPPED except the point of interest is CPR */
#define CPR_VSTOPPED(t)                         \
        ((t)->t_state == TS_SLEEP &&            \
        (t)->t_wchan0 != NULL &&                \
        ((t)->t_flag & T_WAKEABLE) &&           \
        ((t)->t_proc_flag & TP_CHKPT))

/* True if thread has been stopped by hold*() or was created stopped */
#define SUSPENDED(t) ((t)->t_state == TS_STOPPED && \
        ((t)->t_schedflag & (TS_CSTART|TS_UNPAUSE)) != (TS_CSTART|TS_UNPAUSE))

/* True if thread possesses an inherited priority */
#define INHERITED(t)    ((t)->t_epri != 0)

/* The dispatch priority of a thread */
#define DISP_PRIO(t) ((t)->t_epri > (t)->t_pri ? (t)->t_epri : (t)->t_pri)

/* The assigned priority of a thread */
#define ASSIGNED_PRIO(t)        ((t)->t_pri)

/*
 * Macros to determine whether a thread can be swapped.
 * If t_lock is held, the thread is either on a processor or being swapped.
 */
#define SWAP_OK(t)      (!LOCK_HELD(&(t)->t_lock))

/*
 * proctot(x)
 *      convert a proc pointer to a thread pointer. this only works with
 *      procs that have only one lwp.
 *
 * proctolwp(x)
 *      convert a proc pointer to a lwp pointer. this only works with
 *      procs that have only one lwp.
 *
 * ttolwp(x)
 *      convert a thread pointer to its lwp pointer.
 *
 * ttoproc(x)
 *      convert a thread pointer to its proc pointer.
 *
 * ttoproj(x)
 *      convert a thread pointer to its project pointer.
 *
 * ttozone(x)
 *      convert a thread pointer to its zone pointer.
 *
 * lwptot(x)
 *      convert a lwp pointer to its thread pointer.
 *
 * lwptoproc(x)
 *      convert a lwp to its proc pointer.
 */
#define proctot(x)      ((x)->p_tlist)
#define proctolwp(x)    ((x)->p_tlist->t_lwp)
#define ttolwp(x)       ((x)->t_lwp)
#define ttoproc(x)      ((x)->t_procp)
#define ttoproj(x)      ((x)->t_proj)
#define ttozone(x)      ((x)->t_procp->p_zone)
#define lwptot(x)       ((x)->lwp_thread)
#define lwptoproc(x)    ((x)->lwp_procp)

#define t_pc            t_pcb.val[0]
#define t_sp            t_pcb.val[1]

#ifdef  _KERNEL

extern  kthread_t       *threadp(void); /* inline, returns thread pointer */
#define curthread       (threadp())             /* current thread pointer */
#define curproc         (ttoproc(curthread))    /* current process pointer */
#define curproj         (ttoproj(curthread))    /* current project pointer */
#define curzone         (curproc->p_zone)       /* current zone pointer */

extern  struct _kthread t0;             /* the scheduler thread */
extern  kmutex_t        pidlock;        /* global process lock */

/*
 * thread_free_lock is used by the tick accounting thread to keep a thread
 * from being freed while it is being examined.
 *
 * Thread structures are 32-byte aligned structures. That is why we use the
 * following formula.
 */
#define THREAD_FREE_BITS        10
#define THREAD_FREE_NUM         (1 << THREAD_FREE_BITS)
#define THREAD_FREE_MASK        (THREAD_FREE_NUM - 1)
#define THREAD_FREE_1           PTR24_LSB
#define THREAD_FREE_2           (PTR24_LSB + THREAD_FREE_BITS)
#define THREAD_FREE_SHIFT(t)    \
        (((ulong_t)(t) >> THREAD_FREE_1) ^ ((ulong_t)(t) >> THREAD_FREE_2))
#define THREAD_FREE_HASH(t)     (THREAD_FREE_SHIFT(t) & THREAD_FREE_MASK)

typedef struct thread_free_lock {
        kmutex_t        tf_lock;
        uchar_t         tf_pad[64 - sizeof (kmutex_t)];
} thread_free_lock_t;

extern void     thread_free_prevent(kthread_t *);
extern void     thread_free_allow(kthread_t *);

/*
 * Routines to change the priority and effective priority
 * of a thread-locked thread, whatever its state.
 */
extern int      thread_change_pri(kthread_t *t, pri_t disp_pri, int front);
extern void     thread_change_epri(kthread_t *t, pri_t disp_pri);

/*
 * Routines that manipulate the dispatcher lock for the thread.
 * The locking heirarchy is as follows:
 *      cpu_lock > sleepq locks > run queue locks
 */
void    thread_transition(kthread_t *); /* move to transition lock */
void    thread_stop(kthread_t *);       /* move to stop lock */
void    thread_lock(kthread_t *);       /* lock thread and its queue */
void    thread_lock_high(kthread_t *);  /* lock thread and its queue */
void    thread_onproc(kthread_t *, struct cpu *); /* set onproc state lock */

#define thread_unlock(t)                disp_lock_exit((t)->t_lockp)
#define thread_unlock_high(t)           disp_lock_exit_high((t)->t_lockp)
#define thread_unlock_nopreempt(t)      disp_lock_exit_nopreempt((t)->t_lockp)

#define THREAD_LOCK_HELD(t)     (DISP_LOCK_HELD((t)->t_lockp))

extern disp_lock_t transition_lock;     /* lock protecting transiting threads */
extern disp_lock_t stop_lock;           /* lock protecting stopped threads */

caddr_t thread_stk_init(caddr_t);       /* init thread stack */

int thread_setname(kthread_t *, const char *);
int thread_vsetname(kthread_t *, const char *, ...);

extern int default_binding_mode;

#endif  /* _KERNEL */

#define THREAD_NAME_MAX 32      /* includes terminating NUL */

/*
 * Macros to indicate that the thread holds resources that could be critical
 * to other kernel threads, so this thread needs to have kernel priority
 * if it blocks or is preempted.  Note that this is not necessary if the
 * resource is a mutex or a writer lock because of priority inheritance.
 *
 * The only way one thread may legally manipulate another thread's t_kpri_req
 * is to hold the target thread's thread lock while that thread is asleep.
 * (The rwlock code does this to implement direct handoff to waiting readers.)
 */
#define THREAD_KPRI_REQUEST()   (curthread->t_kpri_req++)
#define THREAD_KPRI_RELEASE()   (curthread->t_kpri_req--)
#define THREAD_KPRI_RELEASE_N(n) (curthread->t_kpri_req -= (n))

/*
 * Macro to change a thread's priority.
 */
#define THREAD_CHANGE_PRI(t, pri) {                                     \
        pri_t __new_pri = (pri);                                        \
        DTRACE_SCHED2(change__pri, kthread_t *, (t), pri_t, __new_pri); \
        (t)->t_pri = __new_pri;                                         \
        schedctl_set_cidpri(t);                                         \
}

/*
 * Macro to indicate that a thread's priority is about to be changed.
 */
#define THREAD_WILLCHANGE_PRI(t, pri) {                                 \
        DTRACE_SCHED2(change__pri, kthread_t *, (t), pri_t, (pri));     \
}

/*
 * Macros to change thread state and the associated lock.
 */
#define THREAD_SET_STATE(tp, state, lp) \
                ((tp)->t_state = state, (tp)->t_lockp = lp)

/*
 * Point it at the transition lock, which is always held.
 * The previosly held lock is dropped.
 */
#define THREAD_TRANSITION(tp)   thread_transition(tp);
/*
 * Set the thread's lock to be the transition lock, without dropping
 * previosly held lock.
 */
#define THREAD_TRANSITION_NOLOCK(tp)    ((tp)->t_lockp = &transition_lock)

/*
 * Put thread in run state, and set the lock pointer to the dispatcher queue
 * lock pointer provided.  This lock should be held.
 */
#define THREAD_RUN(tp, lp)      THREAD_SET_STATE(tp, TS_RUN, lp)

/*
 * Put thread in wait state, and set the lock pointer to the wait queue
 * lock pointer provided.  This lock should be held.
 */
#define THREAD_WAIT(tp, lp)     THREAD_SET_STATE(tp, TS_WAIT, lp)

/*
 * Put thread in run state, and set the lock pointer to the dispatcher queue
 * lock pointer provided (i.e., the "swapped_lock").  This lock should be held.
 */
#define THREAD_SWAP(tp, lp)     THREAD_SET_STATE(tp, TS_RUN, lp)

/*
 * Put the thread in zombie state and set the lock pointer to NULL.
 * The NULL will catch anything that tries to lock a zombie.
 */
#define THREAD_ZOMB(tp)         THREAD_SET_STATE(tp, TS_ZOMB, NULL)

/*
 * Set the thread into ONPROC state, and point the lock at the CPUs
 * lock for the onproc thread(s).  This lock should be held, so the
 * thread deoes not become unlocked, since these stores can be reordered.
 */
#define THREAD_ONPROC(tp, cpu)  \
                THREAD_SET_STATE(tp, TS_ONPROC, &(cpu)->cpu_thread_lock)

/*
 * Set the thread into the TS_SLEEP state, and set the lock pointer to
 * to some sleep queue's lock.  The new lock should already be held.
 */
#define THREAD_SLEEP(tp, lp)    {                               \
                        disp_lock_t     *tlp;                   \
                        tlp = (tp)->t_lockp;                    \
                        THREAD_SET_STATE(tp, TS_SLEEP, lp);     \
                        disp_lock_exit_high(tlp);               \
                        }

/*
 * Interrupt threads are created in TS_FREE state, and their lock
 * points at the associated CPU's lock.
 */
#define THREAD_FREEINTR(tp, cpu)        \
                THREAD_SET_STATE(tp, TS_FREE, &(cpu)->cpu_thread_lock)

/* if tunable kmem_stackinfo is set, fill kthread stack with a pattern */
#define KMEM_STKINFO_PATTERN    0xbadcbadcbadcbadcULL

/*
 * If tunable kmem_stackinfo is set, log the latest KMEM_LOG_STK_USAGE_SIZE
 * dead kthreads that used their kernel stack the most.
 */
#define KMEM_STKINFO_LOG_SIZE   16

/* kthread name (cmd/lwpid) string size in the stackinfo log */
#define KMEM_STKINFO_STR_SIZE   64

/*
 * stackinfo logged data.
 */
typedef struct kmem_stkinfo {
        caddr_t kthread;        /* kthread pointer */
        caddr_t t_startpc;      /* where kthread started */
        caddr_t start;          /* kthread stack start address */
        size_t  stksz;          /* kthread stack size */
        size_t  percent;        /* kthread stack high water mark */
        id_t    t_tid;          /* kthread id */
        char    cmd[KMEM_STKINFO_STR_SIZE];     /* kthread name (cmd/lwpid) */
} kmem_stkinfo_t;

#ifdef  __cplusplus
}
#endif

#endif /* _SYS_THREAD_H */