Пример #1
0
/*
 * Define the code needed before returning to user mode, for trap and
 * syscall.
 */
void
userret(struct thread *td, struct trapframe *frame)
{
	struct proc *p = td->td_proc;

	CTR3(KTR_SYSC, "userret: thread %p (pid %d, %s)", td, p->p_pid,
            td->td_name);
	KASSERT((p->p_flag & P_WEXIT) == 0,
	    ("Exiting process returns to usermode"));
#if 0
#ifdef DIAGNOSTIC
	/* Check that we called signotify() enough. */
	PROC_LOCK(p);
	thread_lock(td);
	if (SIGPENDING(td) && ((td->td_flags & TDF_NEEDSIGCHK) == 0 ||
	    (td->td_flags & TDF_ASTPENDING) == 0))
		printf("failed to set signal flags properly for ast()\n");
	thread_unlock(td);
	PROC_UNLOCK(p);
#endif
#endif
#ifdef KTRACE
	KTRUSERRET(td);
#endif
	/*
	 * If this thread tickled GEOM, we need to wait for the giggling to
	 * stop before we return to userland
	 */
	if (td->td_pflags & TDP_GEOM)
		g_waitidle();

	/*
	 * Charge system time if profiling.
	 */
	if (p->p_flag & P_PROFIL)
		addupc_task(td, TRAPF_PC(frame), td->td_pticks * psratio);
	/*
	 * Let the scheduler adjust our priority etc.
	 */
	sched_userret(td);
	KASSERT(td->td_locks == 0,
	    ("userret: Returning with %d locks held.", td->td_locks));
#ifdef VIMAGE
	/* Unfortunately td_vnet_lpush needs VNET_DEBUG. */
	VNET_ASSERT(curvnet == NULL,
	    ("%s: Returning on td %p (pid %d, %s) with vnet %p set in %s",
	    __func__, td, p->p_pid, td->td_name, curvnet,
	    (td->td_vnet_lpush != NULL) ? td->td_vnet_lpush : "N/A"));
#endif
#ifdef XEN
	PT_UPDATES_FLUSH();
#endif
}
Пример #2
0
/*
 * Define the code needed before returning to user mode, for trap and
 * syscall.
 */
void
userret(struct thread *td, struct trapframe *frame)
{
	struct proc *p = td->td_proc;

	CTR3(KTR_SYSC, "userret: thread %p (pid %d, %s)", td, p->p_pid,
            td->td_name);
	KASSERT((p->p_flag & P_WEXIT) == 0,
	    ("Exiting process returns to usermode"));
#if 0
#ifdef DIAGNOSTIC
	/* Check that we called signotify() enough. */
	PROC_LOCK(p);
	thread_lock(td);
	if (SIGPENDING(td) && ((td->td_flags & TDF_NEEDSIGCHK) == 0 ||
	    (td->td_flags & TDF_ASTPENDING) == 0))
		printf("failed to set signal flags properly for ast()\n");
	thread_unlock(td);
	PROC_UNLOCK(p);
#endif
#endif
#ifdef KTRACE
	KTRUSERRET(td);
#endif
	/*
	 * If this thread tickled GEOM, we need to wait for the giggling to
	 * stop before we return to userland
	 */
	if (td->td_pflags & TDP_GEOM)
		g_waitidle();

	/*
	 * Charge system time if profiling.
	 */
	if (p->p_flag & P_PROFIL)
		addupc_task(td, TRAPF_PC(frame), td->td_pticks * psratio);
	/*
	 * Let the scheduler adjust our priority etc.
	 */
	sched_userret(td);
#ifdef XEN
	PT_UPDATES_FLUSH();
#endif

	/*
	 * Check for misbehavior.
	 *
	 * In case there is a callchain tracing ongoing because of
	 * hwpmc(4), skip the scheduler pinning check.
	 * hwpmc(4) subsystem, infact, will collect callchain informations
	 * at ast() checkpoint, which is past userret().
	 */
	WITNESS_WARN(WARN_PANIC, NULL, "userret: returning");
	KASSERT(td->td_critnest == 0,
	    ("userret: Returning in a critical section"));
	KASSERT(td->td_locks == 0,
	    ("userret: Returning with %d locks held", td->td_locks));
	KASSERT(td->td_rw_rlocks == 0,
	    ("userret: Returning with %d rwlocks held in read mode",
	    td->td_rw_rlocks));
	KASSERT((td->td_pflags & TDP_NOFAULTING) == 0,
	    ("userret: Returning with pagefaults disabled"));
	KASSERT(td->td_no_sleeping == 0,
	    ("userret: Returning with sleep disabled"));
	KASSERT(td->td_pinned == 0 || (td->td_pflags & TDP_CALLCHAIN) != 0,
	    ("userret: Returning with with pinned thread"));
	KASSERT(td->td_vp_reserv == 0,
	    ("userret: Returning while holding vnode reservation"));
	KASSERT((td->td_flags & TDF_SBDRY) == 0,
	    ("userret: Returning with stop signals deferred"));
#ifdef VIMAGE
	/* Unfortunately td_vnet_lpush needs VNET_DEBUG. */
	VNET_ASSERT(curvnet == NULL,
	    ("%s: Returning on td %p (pid %d, %s) with vnet %p set in %s",
	    __func__, td, p->p_pid, td->td_name, curvnet,
	    (td->td_vnet_lpush != NULL) ? td->td_vnet_lpush : "N/A"));
#endif
#ifdef	RACCT
	PROC_LOCK(p);
	while (p->p_throttled == 1)
		msleep(p->p_racct, &p->p_mtx, 0, "racct", 0);
	PROC_UNLOCK(p);
#endif
}